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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
FORM 10-K
 
(Mark One)
þ
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2018
or
 
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from             to            
Commission File No. 001-35186 
Spirit Airlines, Inc.

(Exact name of registrant as specified in its charter)
 
 
 
 
Delaware
 
38-1747023
(State or other jurisdiction of
incorporation or organization)
 
(I.R.S. Employer
Identification No.)
 
 
2800 Executive Way Miramar, Florida
 
33025
(Address of principal executive offices)
 
(Zip Code)

(954) 447-7920
(Registrant’s telephone number, including area code)
 
Securities registered pursuant to Section 12(b) of the Act:
 
 
 
Title of Each Class
 
Name of Each Exchange on Which Registered
Voting Common Stock, $0.0001 par value Non-Voting Common Stock, $0.0001 par value
 
New York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act:
None
 
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  þ    No  ¨
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ¨    No  þ
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  þ    No  ¨
Indicate by checkmark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes  þ    No  ¨




Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  þ
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer  þ     Accelerated filer    ¨      Non-accelerated filer   ¨     Smaller reporting company  ¨ Emerging growth company   ¨
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.     ¨
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  þ
The aggregate market value of the common stock held by non-affiliates of the registrant was approximately $2.5 billion computed by reference to the last sale price of the common stock on the New York Stock Exchange on June 30, 2018, the last trading day of the registrant’s most recently completed second fiscal quarter. Shares held by each executive officer, director and by certain persons that own 10 percent or more of the outstanding Common Stock have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.
The number of shares of each registrant's classes of common stock outstanding as of the close of business on February 6, 2019:

Class
Number of Shares
Common Stock, $0.0001 par value per share
68,328,977

Documents Incorporated by Reference

Portions of the registrant's Proxy Statement for the registrant's 2019 Annual Meeting of Stockholders are incorporated by reference into Part III of this Form 10-K to the extent stated herein. The Proxy Statement will be filed within 120 days of the registrant's fiscal year ended December 31, 2018.





TABLE OF CONTENTS
 
PART I
Page
PART II
 
PART III
 
PART IV
 
 
__________________________________________________ 
 





PART I
ITEM 1.    BUSINESS
Overview
Spirit Airlines, headquartered in Miramar, Florida, offers affordable travel to value-conscious customers. Our all-Airbus fleet is one of the youngest and most fuel efficient in the United States. We currently operate more than 500 daily flights to 72 destinations in 16 countries including the United States and throughout Latin America and the Caribbean. Our stock trades under the symbol "SAVE" on the New York Stock Exchange ("NYSE").

Our ultra low-cost carrier, or ULCC, business model allows us to compete principally by offering customers unbundled base fares that remove components traditionally included in the price of an airline ticket. By offering customers unbundled base fares, we give customers the power to save by paying only for the Á La SmarteTM options they choose, such as checked and carry-on bags, advance seat assignments, priority boarding and refreshments. We record revenue related to these options as non-fare passenger revenue, which is recorded within passenger revenues in our statements of operations.

Our History and Corporate Information
We were founded in 1964 as Clippert Trucking Company, a Michigan corporation. We began air charter operations in 1990 and renamed ourselves Spirit Airlines, Inc. in 1992. In 1994, we reincorporated in Delaware, and in 1999 we relocated our headquarters to Miramar, Florida.
Our mailing address and executive offices are located at 2800 Executive Way, Miramar, Florida 33025, and our telephone number at that address is (954) 447-7920. We are subject to the information and periodic reporting requirements of the Securities Exchange Act of 1934, as amended, or Exchange Act, and, in accordance therewith, file periodic reports, proxy statements and other information with the Securities and Exchange Commission or SEC. Such periodic reports, proxy statements and other information are available on the SEC's website at http://www.sec.gov. We also post on the Investor Relations page of our website, www.spirit.com, a link to our filings with the SEC, our Corporate Governance Guidelines and Code of Business Conduct and Ethics, which applies to all directors and all our employees, and the charters of our Audit, Compensation, Finance, Safety, Security and Operations and Nominating and Corporate Governance committees. Our filings with the SEC are posted as soon as reasonably practical after they are filed electronically with the SEC. Please note that information contained on our website is not incorporated by reference in, or considered to be a part of, this report. You can also obtain copies of these documents free of charge by writing to us at: Corporate Secretary, Spirit Airlines, Inc., 2800 Executive Way, Miramar, Florida 33025.
Our Business Model

Our ULCC business model provides customers low, unbundled base fares with a range of optional services, allowing customers the freedom to choose only the options they value. The success of our model is driven by our low-cost structure, which permits us to offer low base fares while maintaining high profit margins.
We are focused on value-conscious travelers who pay for their own travel, and our business model is designed to deliver what our customers want: low fares and a great experience. We use low fares to address underserved markets, which helps us to increase passenger volume and load factors on the flights we operate. We also have high-density seating configurations on our aircraft and a simplified onboard product designed to lower costs. High passenger volumes and load factors help us sell more ancillary products and services, which in turn allows us to reduce the base fare we offer even further. We strive to be recognized by our customers and potential customers as the low-fare leader in the markets we serve.
We compete based on total price. We believe that we and our customers benefit when we allow our customers to know the total price of their travel by breaking out the cost of optional products or services. We allow our customers to see all available options and their respective prices prior to purchasing a ticket, and this full transparency illustrates that our total price, including options selected, is lower on average than other airlines.
Through branded campaigns, we educate the public on how our unbundled pricing model works and show them how it provides a choice on how they spend their money and saves them money compared to other airlines. We show our commitment to delivering the best value in the sky by continuing to make improvements to the customer experience, including a new mobile-friendly website, mobile application, airport kiosks and self bag-tagging in most airports.
Our Strengths

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We believe we compete successfully in the airline industry by leveraging the following demonstrated business strengths:
Ultra Low-Cost Structure. Our unit operating costs are among the lowest of all airlines operating in the United States. We believe this unit cost advantage helps protect our market position and enables us to offer some of the lowest base fares in our markets, sustain among the highest operating margins in our industry and support continued growth. Our operating costs per available seat mile ("CASM") of 8.14 cents in 2018 were significantly lower than those of the major domestic network carriers and among the lowest of the domestic low-cost carriers. We achieve these low unit operating costs in large part due to:
high aircraft utilization;
high-density seating configurations on our aircraft along with a simplified onboard product designed to lower costs;
minimal hub-and-spoke network inefficiencies;
highly productive workforce;
opportunistic outsourcing of operating functions;
operating a single-fleet type of Airbus A320-family aircraft that is one of the youngest and most fuel efficient in the United States and operated by common flight crews;
reduced sales, marketing and distribution costs through direct-to-consumer marketing;
efficient flight scheduling, including minimal ground times between flights; and
a company-wide business culture that is keenly focused on driving costs lower.
Innovative Revenue Generation. We execute our innovative, unbundled pricing strategy to generate significant non-ticket revenue, which allows us to lower base fares and enables our passengers to identify, select and pay for only the products and services they want to use. In implementing our unbundled strategy, we have grown non-ticket revenue per passenger flight segment from approximately $5 in 2006 to $55 in 2018 by:
charging for checked and carry-on baggage;
passing through all distribution-related expenses;
charging for premium seats and advance seat selection;
maintaining consistent ticketing policies, including service charges for changes and cancellations;
generating subscription revenue from our $9 Fare Club low-fare subscription service;
deriving brand-based revenues from proprietary services, such as our FREE SPIRIT affinity credit card program;
offering third-party travel products (travel packages), such as hotel rooms, ground transportation (rental and hotel shuttle products) and attractions (show or theme park tickets) packaged with air travel on our website; and
selling third-party travel insurance through our website.
Resilient Business Model and Customer Base. By focusing on price-sensitive travelers, we have maintained profitability during volatile economic periods because we are not highly dependent on premium-fare business traffic. We believe our growing customer base is more resilient than the customer bases of most other airlines because our low fares and unbundled service offering appeal to price-sensitive travelers.
Well Positioned for Growth. We have developed a substantial network of destinations in profitable U.S. domestic niche markets, targeted growth markets in the Caribbean and Latin America and high-volume routes flown by price-sensitive travelers. In the United States, we also have grown into large markets that, due to higher fares, have priced out those more price-sensitive travelers. We seek to balance growth between large domestic markets, large leisure destinations and opportunities in the Caribbean and Latin America according to current economic and industry conditions.
Experienced International Operator. We believe we have substantial experience in foreign aviation, security and customs regulations, local ground operations and flight crew training required for successful international and overwater flight operations. All of our aircraft are certified for overwater operations. We believe we compete favorably against other low-cost carriers because we have been conducting international flight operations since 2003 and have developed substantial experience in complying with the various regulations and business practices in the international markets we serve. During 2018, 2017 and 2016, no revenue from any one foreign country represented greater than 4% of our total passenger revenue. We attribute operating revenues by geographic region based upon the origin and destination of each passenger flight segment.

5



Financial Strength Achieved with Focus on Cost Discipline. We believe our ULCC business model has delivered strong financial results in both favorable and more difficult economic times. We have generated these results by:
keeping a consistent focus on maintaining low unit operating costs;
ensuring our sourcing arrangements with key third parties are regularly benchmarked against the best industry standards;
generating and maintaining an adequate level of liquidity to insulate against volatility in key cost inputs, such as fuel, and in passenger demand that may occur as a result of changing general economic conditions.
Route Network
As of December 31, 2018, our route network included 279 markets served by 72 airports throughout United States, Latin America and the Caribbean.
Below is a route map of our current network, which includes seasonal routes and routes announced as of January 21, 2019 for which service has not yet started:
396731595_a27788spiritroutemap0124pres.jpg
Our network expansion targets underserved and/or overpriced markets. We employ a rigorous process to identify opportunities to deploy new aircraft where we believe they will be most profitable. To monitor the profitability of each route, we analyze weekly and monthly profitability reports as well as near-term forecasting.
Competition
The airline industry is highly competitive. The principal competitive factors in the airline industry are fare pricing, total price, flight schedules, aircraft type, passenger amenities, number of routes served from a city, customer service, safety record and reputation, code-sharing relationships and frequent flyer programs and redemption opportunities. Our competitors and potential competitors include traditional network airlines, other low-cost carriers and ULCCs, and regional airlines. We

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typically compete in markets served by traditional network airlines, and other low-cost carriers and ULCCs, and, to a lesser extent, regional airlines.
As of December 31, 2018, our top two largest network overlaps are with Southwest Airlines and American Airlines at approximately 59% and 48% of our markets, respectively. Our principal competitors on domestic routes are Southwest Airlines, American Airlines, Delta Air Lines and United Airlines. Our principal competitors to our markets in the Caribbean and Latin America are American Airlines, JetBlue Airways, Southwest Airlines and United Airlines. Our principal competitive advantage is our relative cost advantage which allows us to offer low base fares profitably. In 2018, our unit operating costs were among the lowest in the U.S. airline industry. In difficult economic or competitive environments, we believe our low unit costs coupled with our relatively stable non-ticket revenues allow us to price our fares at levels where we can be profitable while our primary competitors cannot.
The airline industry is particularly susceptible to price discounting because, once a flight is scheduled, airlines incur only nominal incremental costs to provide service to passengers occupying otherwise unsold seats. The expenses of a scheduled aircraft flight do not vary significantly with the number of passengers carried and, as a result, a relatively small change in the number of passengers or in pricing could have a disproportionate effect on an airline’s operating and financial results. Price competition occurs on a market-by-market basis through price discounts, changes in pricing structures, fare matching, target promotions and frequent flyer initiatives. Airlines typically use discount fares and other promotions to stimulate traffic during normally slower travel periods to generate cash flow and to maximize TRASM. The prevalence of discount fares can be particularly acute when a competitor has excess capacity that it is unable to fill at higher rates. A key element to our competitive strategy is to maintain very low unit costs in order to permit us to compete successfully in price-sensitive markets.

Seasonality

Our business is subject to significant seasonal fluctuations. We generally expect demand to be greater in the second and third quarters each year due to more vacation travel during these periods, as compared to the rest of the year. The air transportation business is also volatile and highly affected by economic cycles and trends.
Distribution

The majority of our tickets are sold through direct channels, including online via www.spirit.com, our call center and our airport ticket counters, with www.spirit.com being the primary channel. We also partner with a number of third parties to distribute our tickets, including online and traditional travel agents and electronic global distribution systems.
Customers

We believe our customers are primarily leisure travelers who are paying for their own ticket and who make their purchase decision based largely on price. By maintaining a low cost structure, we can successfully sell tickets at low fares while maintaining a strong profit margin.
Customer Service
We are committed to taking care of our customers. We believe focusing on customer service in every aspect of our operations, including personnel, flight equipment, in-flight and ancillary amenities, on-time performance, flight completion ratios, and baggage handling, will strengthen customer loyalty and attract new customers. We proactively aim to improve our operations to ensure further improvement in customer service.
Our online booking process allows our customers to see all available options and their prices prior to purchasing a ticket. We maintain a campaign that illustrates our total prices are lower, on average, than those of our competitors, even when options are included.
Fleet
We fly only Airbus A320 family aircraft, which provides us significant operational and cost advantages compared to airlines that operate multiple aircraft types. By operating a single aircraft type, we avoid the incremental costs of training crews across multiple types. Flight crews are entirely interchangeable across all of our aircraft, and maintenance, spare parts inventories and other operational support remains highly simplified compared to those airlines with more complex fleets. Due to this commonality among Airbus single-aisle aircraft, we can retain the benefits of a fleet comprised of a single type of aircraft while still having the flexibility to match the capacity and range of the aircraft to the demands of each route.

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As of December 31, 2018, we had a fleet of 128 Airbus single-aisle aircraft, which are commonly referred to as “A320 family” aircraft. A320 family aircraft include the A319, A320 and A321 models, which have broadly common design and equipment but differ most notably in fuselage length, service range and seat capacity. Within the A320 family of aircraft, models using existing engine technology may carry the suffix “ceo,” denoting the “current engine option,” while models equipped with new-generation engines may carry the suffix “neo,” denoting the “new engine option.” As of December 31, 2018, our fleet consisted of 31 A319s, 60 A320ceos, 7 A320neos and 30 A321ceos, and the average age of the fleet was 5.4 years. As of December 31, 2018, we owned 82 of our aircraft, of which 33 aircraft are financed through senior and junior long-term debt with terms of 12 and 7 years, respectively, 27 aircraft are financed through enhanced equipment trust certificates ("EETCs"), and 22 aircraft were purchased off lease and are currently unencumbered. Refer to “Notes to the Financial Statements—13. Debt and Other Obligations” for information regarding our debt financing and “Notes to the Financial Statements—5. Special Charges” for information regarding our aircraft purchased off lease. The remaining 46 of our aircraft are financed under operating leases with expirations between 2021 and 2030. In addition, as of December 31, 2018, we had 12 spare engines financed under operating leases and owned 8 spare engines.
As of December 31, 2018, firm aircraft orders consisted of 50 A320 family aircraft (2 A320ceos and 43 A320neos with Airbus and an additional 5 direct operating leases for A320neos with a third-party lessor). During the first quarter of 2018, we negotiated revisions to our A320 aircraft order with Airbus. We originally had 14 A320neo aircraft scheduled for delivery in 2019. Pursuant to the revision, 5 of the 14 scheduled A320neo aircraft were converted to A320ceo aircraft, of which 3 were delivered in the fourth quarter of 2018 and the remaining 2 are scheduled to be delivered in 2019. As of December 31, 2018, spare engine orders consisted of two V2500 SelectTwo engines with IAE and eight PurePower PW 1100G-JM engines with Pratt & Whitney. Aircraft are scheduled for delivery from 2019 through 2021 and spare engines are scheduled for delivery from 2019 through 2024. The firm aircraft orders provide for capacity growth as well as the flexibility to add to, or replace, the aircraft in our present fleet. We may elect to supplement these deliveries by additional acquisitions from the manufacturer or in the open market if demand conditions merit. We also may adjust or defer deliveries, or change models of aircraft in our delivery stream, from time to time, as a means to match our future capacity with anticipated demand and growth trends.
Consistent with our ULCC business model, each of our aircraft is configured with a high density seating configuration, which helps us maintain a lower unit cost and pass savings to our customers. Our high density seating configuration accommodates more passengers than those of our competitors when comparing the same type of aircraft.
Maintenance and Repairs
We have a Federal Aviation Administration ("FAA") mandated and approved maintenance program, which is administered by our technical services department. Our maintenance technicians undergo extensive initial and ongoing training to ensure the safety of our aircraft.
Aircraft maintenance and repair consists of routine and non-routine maintenance, and work performed is divided into three general categories: line maintenance, heavy maintenance and component service. Line maintenance consists of routine daily and weekly scheduled maintenance checks on our aircraft, including pre-flight, daily, weekly and overnight checks, and any diagnostics and routine repairs and any unscheduled items on an as needed basis. Line maintenance events are currently serviced by in-house mechanics supplemented by contract labor and are primarily completed at airports we currently serve. Heavy airframe maintenance checks consist of a series of more complex tasks that can take from one to four weeks to accomplish and typically are required approximately every 24 to 36 months. Heavy engine maintenance is performed approximately every six years and includes a more complex scope of work. Due to our relatively small fleet size and projected fleet growth, we believe outsourcing all of our heavy maintenance activity, such as engine servicing, heavy airframe maintenance checks, major part repair and component service repairs is more economical. Outsourcing eliminates the substantial initial capital requirements inherent in heavy aircraft maintenance. We have entered into a long-term flight hour agreement for our current fleet and future deliveries with IAE and Pratt & Whitney for our engine overhaul services and with Lufthansa Technik on an hour-by-hour basis for component services. We outsource our heavy airframe maintenance to FAA-qualified maintenance providers.
Our recent maintenance expenses have been lower than what we expect to incur in the future because of the relatively young age of our aircraft fleet. Our maintenance costs are expected to increase as the scope of repairs increases with the increasing age of our fleet. As our aircraft age, scheduled scope of work and frequency of unscheduled maintenance events is likely to increase like any maturing fleet. Our aircraft utilization rate could decrease with the increase in aircraft maintenance.
In the first quarter of 2017, we opened a 126,000-square-foot maintenance hangar facility, adjacent to the airfield at the Detroit Metropolitan Wayne County Airport, which allows us to fulfill the maintenance requirements of our growing fleet and will reduce dependence on third-party facilities and contract line maintenance. Please see “-Properties-Ground Facilities.”
Employees

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Our business is labor intensive, with labor costs representing approximately 24.2%, 23.4% and 25.2% of our total operating costs for 2018, 2017 and 2016, respectively. As of December 31, 2018, we had 2,082 pilots, 3,460 flight attendants, 54 dispatchers, 277 ramp service agents, 249 passenger service agents, 712 maintenance personnel, 196 airport agents/other and 678 employees in administrative roles for a total of 7,708 employees. As of December 31, 2018, approximately 80% of our employees were represented by five labor unions. On an average full-time equivalent basis, for the full year 2018, we had 7,110 employees, compared to 6,100 in 2017.
FAA regulations require pilots to have commercial licenses with specific ratings for the aircraft to be flown and be medically certified as physically fit to fly. FAA and medical certifications are subject to periodic renewal requirements, including recurrent training and recent flying experience. Mechanics, quality-control inspectors and dispatchers must be certificated and qualified for specific aircraft. Flight attendants must have initial and periodic competency training and qualification. Training programs are subject to approval and monitoring by the FAA. Management personnel directly involved in the supervision of flight operations, training, maintenance and aircraft inspection must also meet experience standards prescribed by FAA regulations. All safety-sensitive employees are subject to pre-employment, random and post-accident drug testing.
The Railway Labor Act, or RLA, governs our relations with labor organizations. Under the RLA, our collective bargaining agreements do not expire, but instead become amendable as of a stated date. If either party wishes to modify the terms of any such agreement, they must notify the other party in the manner agreed to by the parties. Under the RLA, after receipt of such notice, the parties must meet for direct negotiations. If no agreement is reached, either party may request the National Mediation Board, or NMB, to appoint a federal mediator. The RLA prescribes no set timetable for the direct negotiation and mediation process. It is not unusual for those processes to last for many months, and even several years. If no agreement is reached in mediation, the NMB in its discretion may declare at some time that an impasse exists. If an impasse is declared, the NMB proffers binding arbitration to the parties. Either party may decline to submit to arbitration. If arbitration is rejected by either party, a 30-day “cooling off” period commences. During that period (or after), a Presidential Emergency Board, or PEB, may be established, which examines the parties’ positions and recommends a solution. The PEB process lasts for 30 days and is followed by another “cooling off” period of 30 days. At the end of a “cooling off” period, unless an agreement is reached or action is taken by Congress, the labor organization and the airline each may resort to “self-help,” including, for the labor organization, a strike or other labor action, and for the airline, the imposition of any or all of its proposed amendments and the hiring of new employees to replace any striking workers. Congress and the President have the authority to prevent “self-help” by enacting legislation that, among other things, imposes a settlement on the parties. The table below sets forth our employee groups and status of the collective bargaining agreements.
Employee Groups
  
Representative
  
Amendable Date
Pilots
  
Air Line Pilots Association, International (ALPA)
  
February 2023
Flight Attendants
  
Association of Flight Attendants (AFA-CWA)
  
May 2021
Dispatchers
  
Professional Airline Flight Control Association (PAFCA)
  
October 2023
Ramp Service Agents
 
International Association of Machinists and Aerospace Workers (IAMAW)
 
June 2020
Passenger Service Agents
 
Transport Workers Union of America (TWU)
 
NA
In August 2015, our collective bargaining agreement with our pilots, represented by ALPA, became amendable. In June 2016, ALPA requested the services of the NMB to facilitate negotiations for an amended agreement and we joined ALPA in the request. In January 2018, under the guidance of the NMB assigned mediators, the parties reached a tentative agreement. In February 2018, the pilot group voted to approve the new five-year agreement. In connection with the new agreement, we incurred a one-time ratification incentive of $80.2 million, including payroll taxes, and an $8.5 million adjustment related to other contractual provisions. These amounts were recorded in special charges within operating expenses in the statement of operations for the year ended December 31, 2018. For additional information, refer to “Notes to the Financial Statements—5. Special Charges.”
In March 2016, under the supervision of the NMB, we reached a tentative agreement for a five-year contract with our flight attendants and in May 2016, the flight attendants voted to approve the new five-year contract. In connection with this agreement, we paid a $9.6 million ratification incentive payment to the flight attendants recorded within salaries, wages and benefits in the statements of operations. Of the total ratification incentive, $8.4 million was recorded during 2016 as the remaining $1.2 million was previously accrued in 2015.
In December 2017, PAFCA filed an application with the NMB seeking to represent our dispatchers, who were previously represented by the TWU.  In January 2018, the NMB determined that a representation election would be held. The voting

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period for the representation election took place through February 20, 2018 and the dispatchers elected to be represented by the PAFCA. In June 2018, we commenced negotiations with PAFCA for an amended agreement with our dispatchers. In October 2018, we reached a tentative agreement for a new five-year agreement, which was ratified by the PAFCA members in October 2018.
In July 2014, certain ramp service agents directly employed by the Company voted to be represented by the IAMAW. In May 2015, we entered into a five-year interim collective bargaining agreement with the IAMAW, covering material economic terms. In June 2016, we reached an agreement on the remaining terms of the collective bargaining agreement, which is amendable in June 2020.
In June 2018, we were notified by the NMB that the TWU filed an application seeking a representation election for our passenger service agents. Our passenger service agents voted to be represented by the TWU, but the representation applies only to the Fort Lauderdale station where we have direct employees in the passenger service classification. We began meeting with the TWU in late October 2018 to negotiate an initial collective bargaining agreement.
We focus on hiring highly productive employees and, where feasible, designing systems and processes around automation and outsourcing in order to maintain our low-cost base.
Safety and Security
We are committed to the safety and security of our passengers and employees. We strive to comply with or exceed health and safety regulation standards. In pursuing these goals, we maintain an active aviation safety program. All of our personnel are expected to participate in the program and take an active role in the identification, reduction and elimination of hazards.
Our ongoing focus on safety relies on training our employees to proper standards and providing them with the tools and equipment they require so they can perform their job functions in a safe and efficient manner. Safety in the workplace targets several areas of our business, including: flight operations, maintenance, in-flight, dispatch and station operations. The Transportation Security Administration, or TSA, is charged with aviation security for both airlines and airports. We maintain active, open lines of communication with the TSA at all of our locations to ensure proper standards for security of our personnel, customers, equipment and facilities are exercised throughout our business.
Insurance
We maintain insurance policies we believe are customary in the airline industry and as required by the Department of Transportation ("DOT"). The policies principally provide liability coverage for public and passenger injury; damage to property; loss of or damage to flight equipment; fire and extended coverage; war risk (terrorism); directors’ and officers’ liability; advertiser and media liability; cyber risk liability; fiduciary; and workers’ compensation and employer’s liability. Renewing coverage could result in a change in premium and more restrictive terms. Although we currently believe our insurance coverage is adequate, there can be no assurance that the amount of such coverage will not be changed or that we will not be forced to bear substantial losses from accidents.
Management Information Systems
We have continued our commitment to technology improvements to support our ongoing operations and initiatives. In 2016, we upgraded the Sabre Flight Operating Suite to Flight Plan Manager. During 2017, we completed the migration of critical operating and sales systems into a state-of-the-art data center facility in South Florida, implemented a new customer mobile application, deployed all new self-service kiosks, and improved the customer experience on our website.
During 2018, we invested in the development of a regionally diverse cloud infrastructure and further network improvements. In 2019, we will continue migrating critical business applications into the cloud infrastructure, allowing us to take increasing advantage of the analytics and automation functions. These improvements provide further opportunities to increase business intelligence and flexibility, improve business continuity, mitigate disaster scenarios and enhance data security. We intend to continue to invest time and resources in upgrading and improving our information systems and the security of our data.
Foreign Ownership
Under DOT regulations and federal law, we must be controlled by U.S. citizens. In order to qualify, at least 75% of our stock must be voted by U.S. citizens, and our president and at least two-thirds of our board of directors and senior management must be U.S. citizens.
We believe we are currently in compliance with such foreign ownership rules.

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Government Regulation
Operational Regulation
The airline industry is heavily regulated, especially by the federal government. Two of the primary regulatory authorities overseeing air transportation in the United States are the DOT and the FAA. The DOT has jurisdiction over economic and consumer issues affecting air transportation, such as competition, route authorizations, advertising and sales practices, baggage liability and disabled passenger transportation, tarmac delays and responding to customer complaints among other areas. In October 2018, following the enactment of the FAA Reauthorization Act of 2018, the DOT enacted an Enforcement Notice addressing the obligations of U.S. carriers to report certain data for mishandled baggage, wheelchairs, and scooters, and established a new compliance date of December 6, 2018. In May 2016, the DOT issued an Advance Notice of Proposed Rulemaking to seek comment on amending its Air Carrier Access Act regarding transportation of service animals, as well as an Interim Statement of Enforcement Priorities Regarding Service Animals to highlight its intended enforcement focus. In 2016, Congress passed a law requiring airlines to refund checked bag fees for delayed bags if they are not delivered to the passenger within a specified number of hours. Though the DOT has been collecting information from carriers and other interested parties and organizations from which to develop a rule, as of January 2019, a rule has not been issued. Additional rules, including disabled passenger rules, may be issued in 2019. See “Risk Factors—Restrictions on or increased taxes applicable to charges for ancillary products and services paid by airline passengers and burdensome consumer protection regulations or laws which could harm our business, results of operations and financial condition."
The DOT has authority to issue certificates of public convenience and necessity required for airlines to provide air transportation. We hold a DOT certificate of public convenience and necessity authorizing us to engage in scheduled air transportation of passengers, property and mail within the United States, its territories and possessions and between the United States and all countries that maintain a liberal aviation trade relationship with the United States (known as “open skies” countries). We also hold DOT certificates to engage in air transportation to certain other countries with more restrictive aviation policies.
The FAA is responsible for regulating and overseeing matters relating to air carrier flight operations, including airline operating certificates, aircraft certification and maintenance and other matters affecting air safety. The FAA requires each commercial airline to obtain and hold an FAA air carrier certificate. This certificate, in combination with operations specifications issued to the airline by the FAA, authorizes the airline to operate at specific airports using aircraft approved by the FAA. As of December 31, 2018, we had FAA airworthiness certificates for all of our aircraft, we had obtained the necessary FAA authority to fly to all of the cities we currently serve, and all of our aircraft had been certified for overwater operations. In 2014, the FAA issued its final regulations governing rest periods and work hours for all airlines certificated under Part 121 of the Federal Aviation Regulations. The rule, known as FAR 117 which became effective on January 4, 2014, impacts the required amount and timing of rest periods for pilots between work assignments, and modifies duty and rest requirements based on the time of day, number of scheduled segments, flight types, time zones and other factors. FAR 117 resulted in increased pilot costs as we were required to hire more pilots in order to comply with the regulations. Any new or revised operational regulations in the future could result in further increased costs. We believe we hold all necessary operating and airworthiness authorizations, certificates and licenses and are operating in compliance with applicable DOT and FAA regulations, interpretations and policies.
International Regulation
All international service is subject to the regulatory requirements of the foreign government involved. We currently offer international service to Aruba, Colombia, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Peru and St. Maarten, as well as Puerto Rico and the U.S. Virgin Islands. If we decide to increase our routes to additional international destinations, we will be required to obtain necessary authority from the DOT and the applicable foreign government. We are also required to comply with overfly regulations in countries that lay along our routes but which we do not serve.
International service is also subject to Customs and Border Protection, or CBP, immigration and agriculture requirements and the requirements of equivalent foreign governmental agencies. Like other airlines flying international routes, from time to time we may be subject to civil fines and penalties imposed by CBP if unmanifested or illegal cargo, such as illegal narcotics, is found on our aircraft. These fines and penalties, which in the case of narcotics are based upon the retail value of the seizure, may be substantial. We have implemented a comprehensive security program at our airports to reduce the risk of illegal cargo being placed on our aircraft, and we seek to cooperate actively with CBP and other U.S. and foreign law enforcement agencies in investigating incidents or attempts to introduce illegal cargo.
Security Regulation

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The TSA was created in 2001 with the responsibility and authority to oversee the implementation, and ensure the adequacy of security measures at airports and other transportation facilities. Funding for passenger security is provided in part by a per enplanement ticket tax (passenger security fee). Prior to and for the first half of 2014, this fee was $2.50 per passenger flight segment, subject to a maximum of $5 per one-way trip. Effective July 1, 2014, the security fee was set at a flat rate of $5.60 each way. On December 19, 2014, the law was amended to limit a round-trip fee to $11.20. In addition, in the past, the TSA has assessed an Aviation Security Infrastructure Fee, or ASIF, on each airline. This fee was eliminated by the TSA effective October 1, 2014. We cannot forecast what additional security and safety requirements may be imposed in the future or the costs or revenue impact that would be associated with complying with such requirements.
Environmental Regulation
We are subject to various federal, state and local laws and regulations relating to the protection of the environment and affecting matters such as aircraft engine emissions, aircraft noise emissions and the discharge or disposal of materials and chemicals, which laws and regulations are administered by numerous state and federal agencies. The Environmental Protection Agency, or EPA, regulates operations, including air carrier operations, which affect the quality of air in the United States. We believe the aircraft in our fleet meet all emission standards issued by the EPA. Concern about climate change and greenhouse gases may result in additional regulation or taxation of aircraft emissions in the United States and abroad.
Federal law recognizes the right of airport operators with special noise problems to implement local noise abatement procedures so long as those procedures do not interfere unreasonably with interstate and foreign commerce and the national air transportation system. These restrictions can include limiting nighttime operations, directing specific aircraft operational procedures during takeoff and initial climb, and limiting the overall number of flights at an airport.
Other Regulations
We are subject to certain provisions of the Communications Act of 1934, as amended, and are required to obtain an aeronautical radio license from the Federal Communications Commission, or FCC. To the extent we are subject to FCC requirements, we will take all necessary steps to comply with those requirements. We are also subject to state and local laws and regulations at locations where we operate and the regulations of various local authorities that operate the airports we serve.
Future Regulations
The U.S. and foreign governments may consider and adopt new laws, regulations, interpretations and policies regarding a wide variety of matters that could directly or indirectly affect our results of operations. We cannot predict what laws, regulations, interpretations and policies might be considered in the future, nor can we judge what impact, if any, the implementation of any of these proposals or changes might have on our business.

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lITEM 1A.    RISK FACTORS
    
Cautionary Statement Regarding Forward-Looking Statements
This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the Securities Act), and Section 21E of the Securities Exchange Act of 1934, as amended (the Exchange Act) which are subject to the “safe harbor” created by those sections. Forward-looking statements are based on our management’s beliefs and assumptions and on information currently available to our management. All statements other than statements of historical facts are “forward-looking statements” for purposes of these provisions. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “would,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “project,” “predict,” “potential,” and similar expressions intended to identify forward-looking statements. Such forward-looking statements are subject to risks, uncertainties and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, those identified below. Furthermore, such forward-looking statements speak only as of the date of this report. Except as required by law, we undertake no obligation to update any forward-looking statements to reflect events or circumstances after the date of such statements. Additional risks or uncertainties (i) that are not currently known to us, (ii) that we currently deem to be immaterial, or (iii) that could apply to any company, could also materially adversely affect our business, financial condition, or future results. You should carefully consider the risks described below and the other information in this report. If any of the following risks materialize, our business could be materially harmed, and our financial condition and results of operations could be materially and adversely affected. References in this report to “Spirit,” “we,” “us,” “our,” or the “Company” shall mean Spirit Airlines, Inc., unless the context indicates otherwise.

Risks Related to Our Industry
We operate in an extremely competitive industry.
We face significant competition with respect to routes, fares and services. Within the airline industry, we compete with traditional network airlines, other low-cost airlines and regional airlines on many of our routes. Competition in most of the destinations we presently serve is intense, sometimes due to the large number of carriers in those markets. Furthermore, other airlines may begin service or increase existing service on routes where we currently face little competition. Most of our competitors are larger than us and have significantly greater financial and other resources than we do.
The airline industry is particularly susceptible to price discounting because once a flight is scheduled, airlines incur only nominal additional costs to provide service to passengers occupying otherwise unsold seats. Increased fare or other price competition has, and may continue to, adversely affect our revenue generation. Moreover, many other airlines have begun to unbundle services by charging separately for services such as baggage and advance seat selection. This unbundling and other cost reducing measures could enable competitor airlines to reduce fares on routes that we serve. Beginning in 2015, and continuing through 2018, the availability of low priced fares coupled with an increase in domestic capacity led to dramatic changes in pricing behavior in many U.S. markets. Many domestic carriers began matching lower cost airline pricing, either with limited or unlimited inventory.
Airlines increase or decrease capacity in markets based on perceived profitability, market share objectives, competitive considerations and other reasons. Decisions by our competitors that increase overall industry capacity, or capacity dedicated to a particular domestic or foreign region, market or route, could have a material adverse impact on our business. If a traditional network airline were to successfully develop a low-cost structure, compete with us on price or if we were to experience increased competition from other low-cost carriers, our business could be materially adversely affected.
Many of the traditional network airlines in the United States have on one or more occasions initiated bankruptcy proceedings in attempts to restructure their debt and other obligations and reduce their operating costs. They also have completed large mergers that have increased their scale and share of the travel market. The mergers between AMR Corporation and US Airways Group, Inc., between Delta Air Lines and Northwest Airlines, between United Airlines and Continental Airlines, between Southwest Airlines and AirTran Airways, and between Alaska Airlines and Virgin America, have created five very large and powerful network airlines, which creates a challenging pricing environment for smaller airlines like us. In the future, there may be additional consolidation in our industry. Any business combination could significantly alter industry conditions and competition within the airline industry, which could have an adverse effect on our business.

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Our growth and the success of our ULCC business model could stimulate competition in our markets through our competitors’ development of their own ULCC strategies, new pricing policies designed to compete with ULCCs or new market entrants. Any such competitor may have greater financial resources and access to less expensive sources of capital than we do, which could enable them to operate their business with a lower cost structure, or enable them to operate with lower-marginal revenues without substantial adverse effects, than we can. If these competitors adopt and successfully execute a ULCC business model, we could be materially adversely affected. In 2015, Delta Air Lines began to market and sell a "Basic Economy" fare which was designed in part to provide its customers with a low base fare similar to Spirit. In 2017, American Airlines and United Airlines announced their "Basic Economy" fare, and other airlines like Alaska Airlines have also followed suit.
The extremely competitive nature of the airline industry could prevent us from attaining the level of passenger traffic or maintaining the level of fares or revenues related to ancillary services required to sustain profitable operations in new and existing markets and could impede our growth strategy, which could harm our operating results. Due to our relatively small size, we are susceptible to a fare war or other competitive activities in one or more of the markets we serve, which could have a material adverse effect on our business, results of operations and financial condition.
Our low-cost structure is one of our primary competitive advantages, and many factors could affect our ability to control our costs.
Our low-cost structure is one of our primary competitive advantages. However, we have limited control over many of our costs. For example, we have limited control over the price and availability of aircraft fuel, aviation insurance, airport costs and related infrastructure taxes, the cost of meeting changing regulatory requirements and our cost to access capital or financing. In addition, the compensation and benefit costs applicable to a significant portion of our employees are established by the terms of our collective bargaining agreements. We cannot guarantee we will be able to maintain a cost advantage over our competitors. If our cost structure increases and we are no longer able to maintain a sufficient cost advantage over our competitors, it could have a material adverse effect on our business, results of operations and financial condition.
The airline industry is heavily influenced by the price and availability of aircraft fuel. Continued volatility in fuel costs or significant disruptions in the supply of fuel, including hurricanes and other events affecting the Gulf Coast in particular, could materially adversely affect our business, results of operations and financial condition.
Aircraft fuel costs represented 31.6%, 27.3% and 23.8% of our total operating expenses for 2018, 2017 and 2016, respectively. As such, our operating results are significantly affected by changes in the availability and the cost of aircraft fuel, especially aircraft fuel refined in the U.S. Gulf Coast region, on which we are highly dependent. Both the cost and the availability of aircraft fuel are subject to many meteorological, economic and political factors and events occurring throughout the world, which we can neither control nor accurately predict. For example, a major hurricane making landfall along the Gulf Coast could disrupt oil production, refinery operations and pipeline capacity in that region, possibly resulting in significant increases in the price of aircraft fuel and diminished availability of aircraft fuel supply. Any disruption to oil production, refinery operations, or pipeline capacity in the Gulf Coast region could have a disproportionate impact on our operating results compared to other airlines that have more diversified fuel sources. Fuel prices also may be affected by geopolitical and macroeconomic conditions and events that are outside of our control, including volatility in the relative strength of the U.S. dollar, the currency in which oil is denominated. Instability within major oil producing regions, such as the Middle East and Venezuela, changes in demand from major petroleum users such as China, and secular increases in competing energy sources are examples of these trends.
Aircraft fuel prices have been subject to high volatility, fluctuating substantially over the past several years. For example, our fuel prices spiked at a high of $3.32 per gallon, in the second quarter of 2012, fell as low as $1.22 per gallon in the first quarter of 2016 and remained at over $2.00 per gallon throughout 2018. We cannot predict the future availability, price volatility or cost of aircraft fuel. Due to the large proportion of aircraft fuel costs in our total operating cost base, even a relatively small increase or decrease in the price of aircraft fuel can have a significant negative impact on our operating costs or revenues and on our business, results of operations and financial condition.
The International Maritime Organization ("IMO") has set January 1, 2020 as the implementation date for ships to comply with its new low sulfur fuel oil requirements. It is uncertain how the availability and price of jet fuel around the world will be affected by the implementation of the IMO 2020 Regulations. Increased costs and/or decreased supply of jet fuel may be material and could adversely affect the Company’s results of operations and financial condition.
Fuel derivative activity, if any, may not reduce fuel costs.
From time to time, we may enter into fuel derivative contracts in order to mitigate the risk to our business from future volatility in fuel prices. Our derivatives may generally consist of United States Gulf Coast jet fuel swaps ("jet fuel swaps") and United States Gulf Coast jet fuel options ("jet fuel options"). Both jet fuel swaps and jet fuel options can be used at times to

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protect the refining risk between the price of crude oil and the price of refined jet fuel, and to manage the risk of increasing fuel prices. As of December 31, 2018, we had no outstanding jet fuel derivatives, and we have not engaged in fuel derivative activity since 2015. There can be no assurance that we will be able to enter into fuel derivative contracts in the future if we are required or choose to do so. Our liquidity and general level of capital resources impacts our ability to hedge our fuel requirements. Even if we are able to hedge portions of our future fuel requirements, we cannot guarantee that our derivative contracts will provide sufficient protection against increased fuel costs or that our counterparties will be able to perform under our derivative contracts, such as in the case of a counterparty’s insolvency. Furthermore, our ability to react to the cost of fuel, absent hedging, is limited because we set the price of tickets in advance of incurring fuel costs. Our ability to pass on any significant increases in aircraft fuel costs through fare increases could also be limited. In the event of a reduction in fuel prices compared to our hedged position, if any, our hedged positions could counteract the cost benefit of lower fuel prices and may require us to post cash margin collateral. Please see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Trends and Uncertainties Affecting Our Business—Aircraft Fuel.”
Restrictions on or increased taxes applicable to charges for ancillary products and services paid by airline passengers and burdensome consumer protection regulations or laws could harm our business, results of operations and financial condition.
During 2018, 2017 and 2016, we generated non-ticket revenues of $1,618.9 million, $1,280.2 million and $1,121.9 million, respectively. Our non-ticket revenues are generated from charges for, among other things, baggage, bookings through certain of our distribution channels, advance seat selection, itinerary changes and loyalty programs. The DOT has rules governing many facets of the airline-consumer relationship, including, for instance, price advertising, tarmac delays, bumping of passengers from flights, ticket refunds and the carriage of disabled passengers. If we are not able to remain in compliance with these rules, the DOT may subject us to fines or other enforcement action, including requirements to modify our passenger reservations system, which could have a material adverse effect on our business. The U.S. Congress and Federal administrative agencies have investigated the increasingly common airline industry practice of unbundling the pricing of certain products and services. If new taxes are imposed on non-ticket revenues, or if other laws or regulations are adopted that make unbundling of airline products and services impermissible, or more cumbersome or expensive, our business, results of operations and financial condition could be harmed. Congressional and other government scrutiny may also change industry practice or public willingness to pay for ancillary services. See also “—We are subject to extensive regulation by the Federal Aviation Administration, the Department of Transportation and other U.S. and foreign governmental agencies, compliance with which could cause us to incur increased costs and adversely affect our business and financial results.”
The airline industry is particularly sensitive to changes in economic conditions. Adverse economic conditions would negatively impact our business, results of operations and financial condition.
Our business and the airline industry in general are affected by many changing economic conditions beyond our control, including, among others:
changes and volatility in general economic conditions, including the severity and duration of any downturn in the U.S. or global economy and financial markets;
changes in consumer preferences, perceptions, spending patterns or demographic trends, including any increased preference for higher-fare carriers offering higher amenity levels, and reduced preferences for low-fare carriers offering more basic transportation;
higher levels of unemployment and varying levels of disposable or discretionary income;
depressed housing and stock market prices; and
lower levels of actual or perceived consumer confidence.
These factors can adversely affect, and from time to time have adversely affected, our results of operations, our ability to obtain financing on acceptable terms and our liquidity. Unfavorable general economic conditions, such as higher unemployment rates, a constrained credit market, housing-related pressures and increased focus on reducing business operating costs can reduce spending for price-sensitive leisure and business travel. For many travelers, in particular the price-sensitive travelers we serve, air transportation is a discretionary purchase that they may reduce or eliminate from their spending in difficult economic times. The overall decrease in demand for air transportation in the United States in 2008 and 2009 resulting from record high fuel prices and the economic recession required us to take significant steps to reduce our capacity, which reduced our revenues. Unfavorable economic conditions could also affect our ability to raise prices to counteract increased fuel, labor or other costs, resulting in a material adverse effect on our business, results of operations and financial condition.

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The airline industry faces ongoing security concerns and related cost burdens, furthered by threatened or actual terrorist attacks or other hostilities that could significantly harm our industry and our business.
The terrorist attacks of September 11, 2001 and their aftermath negatively affected the airline industry. The primary effects experienced by the airline industry included:
substantial loss of revenue and flight disruption costs caused by the grounding of all commercial air traffic in or headed to the United States by the FAA for three days after the terrorist attacks;
increased security and insurance costs;
increased concerns about future terrorist attacks;
airport shutdowns and flight cancellations and delays due to security breaches and perceived safety threats; and
significantly reduced passenger traffic and yields due to the subsequent dramatic drop in demand for air travel.
Since September 11, 2001, the Department of Homeland Security and the TSA have implemented numerous security measures that restrict airline operations and increase costs, and are likely to implement additional measures in the future. For example, following the widely publicized attempt of an alleged terrorist to detonate plastic explosives hidden underneath his clothes on a Northwest Airlines flight on Christmas Day in 2009, passengers became subject to enhanced random screening, which included pat-downs, explosive detection testing and body scans. Enhanced passenger screening, increased regulation governing carry-on baggage and other similar restrictions on passenger travel may further increase passenger inconvenience and reduce the demand for air travel. In addition, increased or enhanced security measures have tended to result in higher governmental fees imposed on airlines, resulting in higher operating costs for airlines, which we may not be able to pass on to consumers in the form of higher prices. Any future terrorist attacks or attempted attacks, even if not made directly on the airline industry, or the fear of such attacks or other hostilities (including elevated national threat warnings or selective cancellation or redirection of flights due to terror threats) would likely have a material adverse effect on our business, results of operations and financial condition and on the airline industry in general.
Airlines are often affected by factors beyond their control, including: air traffic congestion at airports; air traffic control inefficiencies; major construction or improvements at airports; adverse weather conditions, such as hurricanes or blizzards; increased security measures; new travel related taxes or the outbreak of disease, any of which could harm our business, operating results and financial condition.
Like other airlines, our business is affected by factors beyond our control, including air traffic congestion at airports, air traffic control inefficiencies, major construction or improvements at airports at which we operate, adverse weather conditions, increased security measures, new travel related taxes, the outbreak of disease, new regulations or policies from the presidential administration and Congress. Factors that cause flight delays frustrate passengers and increase costs, which in turn could adversely affect profitability. The federal government currently controls all U.S. airspace, and airlines are completely dependent on the FAA to operate that airspace in a safe, efficient and affordable manner. The air traffic control system, which is operated by the FAA, faces challenges in managing the growing demand for U.S. air travel. U.S. and foreign air-traffic controllers often rely on outdated technologies that routinely overwhelm the system and compel airlines to fly inefficient, indirect routes resulting in delays. A significant portion of our operations is concentrated in markets such as South Florida, the Caribbean, Latin America and the Northeast and Northern Midwest regions of the United States, which are particularly vulnerable to weather, airport traffic constraints and other delays. Adverse weather conditions and natural disasters, such as hurricanes affecting southern Florida and the Caribbean (such as Hurricanes Irma and Maria in September 2017) as well as southern Texas (such as Hurricane Harvey in August 2017), winter snowstorms or earthquakes (such as the September 2017 earthquakes in Mexico City, Mexico) can cause flight cancellations, significant delays and certain facility disruptions. For example, during 2017, the timing and location of Hurricanes Irma and Maria produced a domino effect on our operations resulting in approximately 1,400 flight cancellations and numerous flight delays, which resulted in an adverse effect on our results of operations. Cancellations or delays due to adverse weather conditions or natural disasters, air traffic control problems or inefficiencies, breaches in security or other factors may affect us to a greater degree than other, larger airlines that may be able to recover more quickly from these events, and therefore could harm our business, results of operations and financial condition to a greater degree than other air carriers. Because of our high utilization, point-to-point network, operational disruptions can have a disproportionate impact on our ability to recover. In addition, many airlines reaccommodate their disrupted passengers on other airlines at prearranged rates under flight interruption manifest agreements. We have been unsuccessful in procuring any of these agreements with our peers, which makes our recovery from disruption more challenging than for larger airlines that have these agreements in place. Similarly, outbreaks of pandemic or contagious diseases, such as Ebola, measles, avian flu, severe acute respiratory syndrome (SARS), H1N1 (swine) flu and Zika virus, could result in significant decreases in passenger traffic and the imposition of government restrictions in service and could have a material adverse impact on the airline industry.

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Any increases in travel related taxes could also result in decreases in passenger traffic. Any general reduction in airline passenger traffic could have a material adverse effect on our business, results of operations and financial condition. Moreover, U.S. federal government shutdowns may cause delays and cancellations or reductions in discretionary travel due to longer security lines, including as a result of furloughed government employees, or reductions in staffing levels, including air traffic controllers. U.S. government shutdowns may also impact our ability to take delivery of aircraft and commence operations in new domestic stations. Any extended shutdown like the one in January 2019 may have a negative impact on our operations and financial results.
Restrictions on or litigation regarding third-party membership discount programs could harm our business, operating results and financial condition.
We generate a relatively small but growing portion of our revenue from commissions, revenue share and other fees paid to us by third-party merchants for customer click-throughs, distribution of third-party promotional materials and referrals arising from products and services of the third-party merchants that we offer to our customers on our website. Some of these third-party referral-based offers are for memberships in discount programs or similar promotions made to customers who have purchased products from us, and for which we receive a payment from the third-party merchants for every customer that accepts the promotion. Certain of these third-party membership discount programs have been the subject of consumer complaints, litigation and regulatory actions alleging that the enrollment and billing practices involved in the programs violate various consumer protection laws or are otherwise deceptive. Any private or governmental claim or action that may be brought against us in the future relating to these third-party membership programs could result in our being obligated to pay damages or incurring legal fees in defending claims. These damages and fees could be disproportionate to the revenues we generate through these relationships. In addition, customer dissatisfaction or a significant reduction in or termination of the third-party membership discount offers on our website as a result of these claims could have a negative impact on our brand, and have a material adverse effect on our business, results of operations and financial condition.
We face competition from air travel substitutes.
In addition to airline competition from traditional network airlines, other low-cost airlines and regional airlines, we also face competition from air travel substitutes. On our domestic routes, we face competition from some other transportation alternatives, such as bus, train or automobile. In addition, technology advancements may limit the demand for air travel. For example, video teleconferencing and other methods of electronic communication may reduce the need for in-person communication and add a new dimension of competition to the industry as travelers seek lower-cost substitutes for air travel. If we are unable to adjust rapidly in the event the basis of competition in our markets changes, it could have a material adverse effect on our business, results of operations and financial condition.
Risks Related to Our Business
Increased labor costs, union disputes, employee strikes and other labor-related disruption may adversely affect our business, results of operations and financial conditions.
Our business is labor intensive, with labor costs representing approximately 24.2%, 23.4% and 25.2% of our total operating costs for 2018, 2017 and 2016, respectively. As of December 31, 2018, approximately 80% of our workforce was represented by labor unions. We cannot assure that our labor costs going forward will remain competitive because in the future our labor agreements may be amended or become amendable and new agreements could have terms with higher labor costs; one or more of our competitors may significantly reduce their labor costs, thereby reducing or eliminating our comparative advantages as to one or more of such competitors; or our labor costs may increase in connection with our growth. We may also become subject to additional collective bargaining agreements in the future as non-unionized workers may unionize.
Relations between air carriers and labor unions in the United States are governed by the RLA. Under the RLA, collective bargaining agreements generally contain “amendable dates” rather than expiration dates, and the RLA requires that a carrier maintain the existing terms and conditions of employment following the amendable date through a multi-stage and usually lengthy series of bargaining processes overseen by the NMB. This process continues until either the parties have reached agreement on a new collective bargaining agreement, or the parties have been released to “self-help” by the NMB. In most circumstances, the RLA prohibits strikes; however, after release by the NMB, carriers and unions are free to engage in self-help measures such as lockouts and strikes.
In August 2015, the collective bargaining agreement with our pilots, represented by ALPA, became amendable. In June 2016, ALPA requested the services of the National Mediation Board ("NMB") to facilitate negotiations for an amended agreement and we joined ALPA in the request. During 2017, we experienced operational disruption from pilot-related work action which adversely impacted our results. We obtained a temporary restraining order to enjoin further illegal labor action. In January 2018, under the guidance of the NMB assigned mediators, the parties reached a tentative agreement. In February 2018,

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the pilot group voted to approve the new five-year agreement with the Company. In connection with the new agreement, we incurred a one-time ratification incentive of $80.2 million, including payroll taxes, and an $8.5 million adjustment related to other contractual provisions. These amounts were recorded in special charges within operating expenses in the statement of operations for the year ended 2018.
In March 2016, under the supervision of the NMB, we reached a tentative agreement for a five-year contract with our flight attendants. In May 2016, we entered into a five-year agreement with our flight attendants, which becomes amendable May 2021.
In December 2017, PAFCA filed an application with the NMB seeking to represent our dispatchers, who were previously represented by the TWU. In January 2018, the NMB determined that a representation election would be held. The voting period for the representation election took place through February 20, 2018 and the dispatchers elected to be represented by the PAFCA. In June 2018, the Company commenced negotiations with PAFCA for an amended agreement with its dispatchers. In October 2018, PAFCA and the Company reached a tentative agreement for a new five-year agreement, which was ratified by the PAFCA members in October 2018. The terms of the new agreement are currently in effect.
In July 2014, certain ramp service agents directly employed by us voted to be represented by the IAMAW. In May 2015, we entered into a five-year interim collective bargaining agreement with the IAMAW, including material economic terms. In June 2016, we reached an agreement on the remaining terms of the collective bargaining agreement with the IAMAW, which is amendable in June 2020.
In June 2018, the NMB notified the Company that the TWU filed an application seeking a representation election for the Company's passenger service agents. The NMB determined that a representation election would be held and the voting period for the election took place through September 4, 2018. The Company's passenger service agents voted to be represented by the TWU, but the representation applies only to the Company's Fort Lauderdale station where the Company has direct employees in the passenger service classification. The Company and the TWU began meeting in late October 2018 to negotiate an initial collective bargaining agreement.
If we are unable to reach agreement with any of our unionized work groups in current or future negotiations regarding the terms of their CBAs, we may be subject to work interruptions or stoppages, such as the strike by our pilots in June 2010. A strike or other significant labor dispute with our unionized employees is likely to adversely affect our ability to conduct business. Any agreement we do reach could increase our labor and related expenses.
The Patient Protection and Affordable Care Act was enacted in 2010. Under the current administration, this law may be repealed in its entirety or certain aspects may be changed or replaced. If the law is repealed or significantly modified or if new healthcare legislation is passed, such action could significantly increase cost of the healthcare benefits provided to our U.S. employees. In addition, the failure to comply materially with such existing and new laws, rules and regulations could adversely affect our business, results of operations and financial conditions.
We have a significant amount of aircraft-related fixed obligations that could impair our liquidity and thereby harm our business, results of operations and financial condition.
The airline business is capital intensive and, as a result, many airline companies are highly leveraged. As of December 31, 2018, our 128 aircraft fleet consisted of 46 aircraft financed under operating leases, 60 aircraft financed under debt arrangements, and 22 aircraft purchased off lease and currently unencumbered. In 2018 and 2017, we paid the lessors rent of $214.0 million and $220.9 million, respectively. In connection with our aircraft and engines, in 2018, we received maintenance deposits, net of payments, of $14.0 million and in 2017, we paid maintenance deposits, net of reimbursements, of $37.9 million. As of December 31, 2018, we had future aircraft and spare engine operating lease obligations of approximately $1.2 billion. In 2018 and 2017, we made scheduled principal payments of $137.3 million and $102.3 million on our outstanding debt obligations, respectively. As of December 31, 2018, we had future principal debt obligations of $2.2 billion, of which $171.4 million is due in 2019. In addition, we have significant obligations for aircraft and spare engines that we have ordered from Airbus, International Aero Engines AG, or IAE, and Pratt & Whitney for delivery over the next several years. Our ability to pay the fixed costs associated with our contractual obligations will depend on our operating performance, cash flow and our ability to secure adequate financing, which will in turn depend on, among other things, the success of our current business strategy, fuel price volatility, weakening or improvement in the U.S. economy, as well as general economic and political conditions and other factors that are beyond our control. The amount of our aircraft related fixed obligations and related need to obtain financing could have a material adverse effect on our business, results of operations and financial condition and could:
require a substantial portion of cash flow from operations for operating lease and maintenance deposit payments, thereby reducing the availability of our cash flow to fund working capital, capital expenditures and other general corporate purposes;

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limit our ability to make required pre-delivery deposit payments, or PDPs, including those payable to our aircraft and engine manufacturers for our aircraft and spare engines on order;
limit our ability to obtain additional financing to support our expansion plans and for working capital and other purposes on acceptable terms or at all;
make it more difficult for us to pay our other obligations as they become due during adverse general economic and market industry conditions because any related decrease in revenues could cause us to not have sufficient cash flows from operations to make our scheduled payments;
reduce our flexibility in planning for, or reacting to, changes in our business and the airline industry and, consequently, place us at a competitive disadvantage to our competitors with fewer fixed payment obligations; and
cause us to lose access to one or more aircraft and forfeit our rent deposits if we are unable to make our required aircraft lease rental and debt payments and our lessors or lenders exercise their remedies under the lease and debt agreements, including cross default provisions in certain of our leases and mortgages.
A failure to pay our operating lease, debt and other fixed cost obligations or a breach of our contractual obligations could result in a variety of adverse consequences, including the exercise of remedies by our creditors and lessors. In such a situation, it is unlikely that we would be able to cure our breach, fulfill our obligations, make required lease or debt payments or otherwise cover our fixed costs, which would have a material adverse effect on our business, results of operations and financial condition.
We are highly dependent upon our cash balances and operating cash flows.
As of December 31, 2018, we had access to lines of credit from our physical fuel delivery and derivative counterparties and our purchase credit card issuer aggregating $75.1 million and an unsecured standby letter of credit facility of $35.0 million. In addition, during the fourth quarter of 2018, we entered into a revolving credit facility for up to $160 million on which we had drawn $135.3 million as of December 31, 2018. For additional information, refer to "Notes to the Financial Statements—13, Debt and Other Obligations." These credit facilities are not adequate to finance our operations, and we will continue to be dependent on our operating cash flows and cash balances to fund our operations and to make scheduled payments on our aircraft related fixed obligations. In addition, our credit card processors are entitled to withhold receipts from customer purchases from us, under certain circumstances. Although our credit card processors currently do not have a right to hold back credit card receipts to cover repayment to customers, if we fail to maintain certain liquidity and other financial covenants, their rights to holdback would be reinstated, which would result in a reduction of unrestricted cash that could be material. In addition, we are required by some of our aircraft lessors to fund reserves in cash in advance for scheduled maintenance, and a portion of our cash is therefore unavailable until after we have completed the scheduled maintenance in accordance with the terms of the operating leases. Based on the age of our fleet and our growth strategy, these maintenance deposits will increase over the next few years before we receive any significant reimbursement for completed maintenance. If we fail to generate sufficient funds from operations to meet our operating cash requirements or do not obtain a line of credit, other borrowing facility or equity financing, we could default on our operating lease and fixed obligations. Our inability to meet our obligations as they become due would have a material adverse effect on our business, results of operations and financial condition.
A deterioration in worldwide economic conditions may adversely affect our business, operating results, financial condition, liquidity and ability to obtain financing or access capital markets.
The general worldwide economy has in the past experienced downturns due to the effects of the European debt crisis, unfavorable U.S. economic conditions and slowing growth in certain Asian economies, including general credit market crises, collateral effects on the finance and banking industries, energy price volatility, concerns about inflation, slower economic activity, decreased consumer confidence, reduced corporate profits and capital spending, adverse business conditions, geopolitical conflict and liquidity concerns. The airline industry is particularly sensitive to changes in economic conditions, which affect customer travel patterns and related revenues.  A weak economy could reduce our bookings, and a reduction in discretionary spending could also decrease amounts our customers are willing to pay.  Unfavorable economic conditions can also impact the ability of airlines to raise fares to help offset increased fuel, labor and other costs. We cannot accurately predict the effect or duration of any economic slowdown or the timing or strength of a subsequent economic recovery.
In addition, we have significant obligations for aircraft and spare engines that we have ordered from Airbus, IAE and Pratt & Whitney over the next several years, and we will need to finance these purchases. We may not have sufficient liquidity or creditworthiness to fund the purchase of aircraft and engines, including payment of PDPs, or for other working capital. Factors that affect our ability to raise financing or access the capital markets include market conditions in the airline industry, economic conditions, the perceived residual value of aircraft and related assets, the level and volatility of our earnings, our

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relative competitive position in the markets in which we operate, our ability to retain key personnel, our operating cash flows and legal and regulatory developments. Regardless of our creditworthiness, at times the market for aircraft purchase or lease financing has been very constrained due to such factors as the general state of the capital markets and the financial position of the major providers of commercial aircraft financing.
Our liquidity and general level of capital resources impact our ability to hedge our fuel requirements.
From time to time, we may enter into fuel derivative contracts in order to mitigate the risk to our business from future volatility in fuel prices, refining risk between the price of crude oil and the price of refined jet fuel, and to manage the risk of increasing fuel prices. As of December 31, 2018, we had no outstanding jet fuel derivatives and we have not engaged in fuel derivative activity since 2015. There can be no assurance that we will be able to enter into fuel derivative contracts in the future if we are required or choose to do so. In the past, we have not had and in the future we may not have sufficient creditworthiness or liquidity to post the collateral necessary to hedge our fuel requirements. Even if we are able to hedge portions of our future fuel requirements, we cannot guarantee that our derivative contracts will provide any particular level of protection against increased fuel costs or that our counterparties will be able to perform under our derivative contracts, such as in the case of a counterparty’s insolvency. In a falling fuel price environment, we may be required to make cash payments to our counterparties which may impair our liquidity position and increase our costs.
We rely on maintaining a high daily aircraft utilization rate to implement our low-cost structure, which makes us especially vulnerable to flight delays or cancellations or aircraft unavailability.
We maintain a high daily aircraft utilization rate. Our average daily aircraft utilization was 12.1 hours for 2018, 11.6 hours for 2017 and 12.4 hours for 2016. Aircraft utilization is the average amount of time per day that our aircraft spend carrying passengers. Our revenue per aircraft can be increased by high daily aircraft utilization, which is achieved in part by reducing turnaround times at airports so we can fly more hours on average in a day. Aircraft utilization is reduced by delays and cancellations from various factors, many of which are beyond our control, including air traffic congestion at airports or other air traffic control problems, adverse weather conditions, increased security measures or breaches in security, international or domestic conflicts, terrorist activity, or other changes in business conditions. A significant portion of our operations are concentrated in markets such as South Florida, the Caribbean, Latin America and the Northeast and northern Midwest regions of the United States, which are particularly vulnerable to weather, airport traffic constraints and other delays. In addition, pulling aircraft out of service for unscheduled and scheduled maintenance, the occurrence of which will increase as our fleet ages, may materially reduce our average fleet utilization and require that we seek short-term substitute capacity at increased costs. Due to the relatively small size of our fleet and high daily aircraft utilization rate, the unavailability of aircraft and resulting reduced capacity could have a material adverse effect on our business, results of operations and financial condition.
Our maintenance costs will increase as our fleet ages, and we will periodically incur substantial maintenance costs due to the maintenance schedules of our aircraft fleet.
As of December 31, 2018, the average age of our aircraft was approximately 5.4 years. Our relatively new aircraft require less maintenance now than they will in the future. Our fleet will require more maintenance as it ages and our maintenance and repair expenses for each of our aircraft will be incurred at approximately the same intervals. For our leased aircraft, we expect that the final heavy maintenance events will be amortized over the remaining lease term rather than until the next estimated heavy maintenance event, because we account for heavy maintenance under the deferral method. This will result in significantly higher depreciation and amortization expense related to heavy maintenance in the last few years of the leases as compared to the costs in earlier periods. Moreover, because our current fleet was acquired over a relatively short period, significant maintenance that is scheduled on each of these planes is occurring at roughly the same time, meaning we will incur our most expensive scheduled maintenance obligations, known as heavy maintenance, across our present fleet around the same time. These more significant maintenance activities result in out-of-service periods during which our aircraft are dedicated to maintenance activities and unavailable to fly revenue service. In addition, the terms of some of our lease agreements require us to pay maintenance reserves to the lessor in advance of the performance of major maintenance, resulting in our recording significant prepaid deposits on our balance sheet. Depending on their recoverability, these maintenance reserves may be classified as supplemental rent. We expect scheduled and unscheduled aircraft maintenance expenses to increase over the next several years. Any significant increase in maintenance and repair expenses would have a material adverse effect on our business, results of operations and financial condition. Please see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates—Aircraft Maintenance, Materials and Repair Costs and Heavy Maintenance Amortization” and “—Maintenance Reserves.”
Our lack of marketing alliances could harm our business.
Many airlines, including the domestic traditional network airlines (American, Delta and United) have marketing alliances with other airlines, under which they market and advertise their status as marketing alliance partners. These alliances, such as

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OneWorld, SkyTeam and Star Alliance, generally provide for code-sharing, frequent flyer program reciprocity, coordinated scheduling of flights to permit convenient connections and other joint marketing activities. Such arrangements permit an airline to market flights operated by other alliance members as its own. This increases the destinations, connections and frequencies offered by the airline and provides an opportunity to increase traffic on that airline’s segment of flights connecting with alliance partners. We currently do not have any alliances with U.S. or foreign airlines. Our lack of marketing alliances puts us at a competitive disadvantage to traditional network carriers who are able to attract passengers through more widespread alliances, particularly on international routes, and that disadvantage may result in a material adverse effect on our passenger traffic, business, results of operations and financial condition.
We are subject to extensive and increasing regulation by the FAA, DOT, TSA and other U.S. and foreign governmental agencies, compliance with which could cause us to incur increased costs and adversely affect our business and financial results.

Airlines are subject to extensive and increasing regulatory and legal compliance requirements, both domestically and internationally, that involve significant costs. In the last several years, Congress has passed laws, and the DOT, FAA and TSA have issued regulations, relating to the operation of airlines that have required significant expenditures. We expect to continue to incur expenses in connection with complying with government regulations. Additional laws, regulations, taxes and increased airport rates and charges have been proposed from time to time that could significantly increase the cost of airline operations or reduce the demand for air travel. If adopted, these measures could have the effect of raising ticket prices, reducing revenue and increasing costs.
DOT has been aggressive in enforcing regulations for violations of the tarmac delay rules, passenger with disability rules, advertising rules and other consumer protection rules that could increase the cost of airline operations or reduce revenues. Additional rules on providing scheduling, fare and fee information to travel agents and metasearch sites may be issued in the future. Additional disability rules may be proposed, including with respect to access to lavatories on single-aisle aircraft. In addition, during 2014, the FAA issued its final regulations governing pilot rest periods and work hours for all airlines certificated under Part 121 of the Federal Aviation Regulations. The rule known as FAR 117, which became effective January 4, 2014, impacted the required amount and timing of rest periods for pilots between work assignments and modifies duty and rest requirements based on the time of day, number of scheduled segments, flight types, time zones and other factors. Compliance with these rules may increase our costs, while failure to remain in full compliance with these rules may subject us to fines or other enforcement action.
In October 2018, Congress passed the FAA Reauthorization Act of 2018, which extends FAA funds through fiscal year 2023. The legislation contains provisions which could have effects on our results of operations and financial condition. Among other provisions, the new law requires the DOT to lift the payment cap on denied boarding compensation, create new requirements for the treatment of disabled passengers, and treble the maximum civil penalty for damage to wheelchairs and other assistive devices or for injuring a disabled passenger. The FAA must issue rules establishing minimum dimensions for passenger seats, including seat pitch, width and length. The Act also establishes new rest requirements for flight attendants and requires, within one year, that the FAA issue an order requiring installation of a secondary cockpit barrier on each new aircraft.

We cannot assure that these and other laws or regulations enacted in the future will not harm our business. In addition, the TSA mandates the federalization of certain airport security procedures and imposes additional security requirements on airports and airlines, most of which are funded by a per ticket tax on passengers and a tax on airlines. We cannot forecast what additional security and safety requirements may be imposed in the future or the costs or revenue impact that would be associated with complying with such requirements.

Our ability to operate as an airline is dependent on our maintaining certifications issued to us by the DOT and the FAA. The FAA has the authority to issue mandatory orders relating to, among other things, the grounding of aircraft, inspection of aircraft, installation of new safety-related items and removal and replacement of aircraft parts that have failed or may fail in the future. A decision by the FAA to ground, or require time consuming inspections of or maintenance on, our aircraft, for any reason, could negatively affect our business and financial results. Federal law requires that air carriers operating large aircraft be continuously “fit, willing and able” to provide the services for which they are licensed. Our “fitness” is monitored by the DOT, which considers factors such as unfair or deceptive competition, advertising, baggage liability and disabled passenger transportation. While the DOT has seldom revoked a carrier's certification for lack of fitness, such an occurrence would render it impossible for us to continue operating as an airline. The DOT may also institute investigations or administrative proceedings against airlines for violations of regulations.
    
The U.S. government is under persistent pressure to implement cost cutting and efficiency initiatives. In addition, the U.S. government has recently and may in the future experience delays in the completion of its budget process which could

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delay funding for government departments and agencies that regulate or otherwise are tied to the aviation industry, including the DOT and FAA. To the extent that any such initiatives or budgeting delays affect the operations of these government departments and agencies, including by forcing mandatory furloughs of government employees, our operations and results of operations could be materially adversely affected.

International routes are regulated by treaties and related agreements between the United States and foreign governments. Our ability to operate international routes is subject to change because the applicable arrangements between the United States and foreign governments may be amended from time to time. Our access to new international markets may be limited by our ability to obtain the necessary certificates to fly the international routes. In addition, our operations in foreign countries are subject to regulation by foreign governments and our business may be affected by changes in law and future actions taken by such governments, including granting or withdrawal of government approvals and restrictions on competitive practices. We are subject to numerous foreign regulations based on the large number of countries outside the United States where we currently provide service. If we are not able to comply with this complex regulatory regime, our business could be significantly harmed. Please see “Business — Government Regulation.”

Changes in legislation, regulation and government policy have affected, and may in the future have a material adverse effect on our business.

Changes in, and uncertainty with respect to, legislation, regulation and government policy at the local, state or federal level have affected, and may in the future significantly impact, our business and the airline industry. For example, the Tax Cuts and Jobs Act, enacted on December 22, 2017, limits deductions for borrowers for net interest expense on debt. Specific legislative and regulatory proposals that could have a material impact on us in the future include, but are not limited to, infrastructure renewal programs; changes to immigration policy; modifications to international trade policy, including withdrawing from trade agreements and imposing tariffs; changes to financial legislation, including the partial or full repeal of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, or Dodd-Frank Act; public company reporting requirements; environmental regulation and antitrust enforcement. Any such changes may make it more difficult and/or more expensive for us to obtain new aircraft or engines and parts to maintain existing aircraft or engines or make it less profitable or prevent us from flying to or from some of the destinations we currently serve.

To the extent that any such changes have a negative impact on us or the airline industry, including as a result of related uncertainty, these changes may materially and adversely impact our business, financial condition, results of operations and cash flows.

We may not be able to implement our growth strategy.
Our growth strategy includes acquiring additional aircraft, increasing the frequency of flights and size of aircraft used in markets we currently serve, and expanding the number of markets we serve where our low cost structure would likely be successful. Effectively implementing our growth strategy is critical for our business to achieve economies of scale and to sustain or increase our profitability. We face numerous challenges in implementing our growth strategy, including our ability to:
maintain profitability;
obtain financing to acquire new aircraft;
access airports located in our targeted geographic markets where we can operate routes in a manner that is consistent with our cost strategy;
obtain sufficient spare parts or related support services from our suppliers on a timely basis;
gain access to international routes; and
access sufficient gates and other services at airports we currently serve or may seek to serve.
Our growth is dependent upon our ability to maintain a safe and secure operation and requires additional personnel, equipment and facilities. An inability to hire and retain personnel, timely secure the required equipment and facilities in a cost-effective manner, efficiently operate our expanded facilities or obtain the necessary regulatory approvals may adversely affect our ability to achieve our growth strategy, which could harm our business. In addition, expansion to new markets may have other risks due to factors specific to those markets. We may be unable to foresee all of the existing risks upon entering certain new markets or respond adequately to these risks, and our growth strategy and our business may suffer as a result. In addition, our competitors may reduce their fares and/or offer special promotions to deter our entry into a new market or to stop our

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growth into existing markets or new markets. We cannot assure you that we will be able to profitably expand our existing markets or establish new markets.
Some of our target growth markets in the Caribbean and Latin America include countries with less developed economies that may be vulnerable to unstable economic and political conditions, such as significant fluctuations in gross domestic product, interest and currency exchange rates, high inflation, civil disturbances, government instability, nationalization and expropriation of private assets and the imposition of taxes or other charges by governments. The occurrence of any of these events in markets served by us and the resulting instability may adversely affect our ability to implement our growth strategy.
In 2008, in response to record high fuel prices and rapidly deteriorating economic conditions, we modified our growth plans by terminating our leases for seven aircraft. We incurred significant expenses relating to our lease terminations, and have incurred additional expenses to acquire new aircraft in place of those under the terminated leases as we expanded our network. We may in the future determine to reduce further our future growth plans from previously announced levels, which may impact our business strategy and future profitability.
We rely heavily on technology and automated systems to operate our business and any failure of these technologies or systems or failure by their operators could harm our business.
We are highly dependent on technology and automated systems to operate our business and achieve low operating costs. These technologies and systems include our computerized airline reservation system, flight operations system, financial planning, management and accounting system, telecommunications systems, website, maintenance systems and check-in kiosks. The performance and reliability of our technology are critical to our ability to operate and compete effectively. In 2015, our Board of Directors approved a significant technology upgrade initiative meant to address our aging IT infrastructure. This initiative has and will continue to upgrade, replace, and enhance multiple older and outdated legacy systems and hardware. The execution of our strategic plans could be negatively affected by (i) our ability to timely and effectively implement, transition, and maintain related information technology systems and infrastructure; (ii) our ability to effectively balance our investment of incremental operating expenses and capital expenditures related to our strategies against the need to effectively control cost; and (iii) our dependence on third parties with respect to our ability to implement our strategic plans. We cannot assure you that our security measures, change control procedures, and disaster recovery plans will be adequate to prevent disruptions or delays. Disruption in or changes to these systems could result in an interruption to our operations or loss of important data. Any of the foregoing could result in a material adverse effect on our business, reputation, results of operations and financial condition.
In order for our operations to work efficiently, our website and reservation system must be able to accommodate a high volume of traffic, maintain secure information and deliver flight information with a high degree of reliability. Substantially all of our tickets are issued to passengers as electronic tickets. We depend on our reservation system, which is hosted and maintained under a long-term contract by a third-party service provider, to be able to issue, track and accept these electronic tickets. If our reservation system fails or experiences interruptions, and we are unable to book seats for any period of time, we could lose a significant amount of revenue as customers book seats on competing airlines. We have experienced short duration reservation system outages from time to time and may experience similar outages in the future. For example, in November 2010, we experienced a significant service outage with our third-party reservation service provider on the day before Thanksgiving, one of the industry’s busiest travel days and in August 2013, we experienced a 13-hour outage that affected our sales and customer service response times. We also rely on third-party service providers of our other automated systems for technical support, system maintenance and software upgrades. If our automated systems are not functioning or if the current providers were to fail to adequately provide technical support or timely software upgrades for any one of our key existing systems, we could experience service disruptions, which could harm our business and result in the loss of important data, increase our expenses and decrease our revenues. In the event that one or more of our primary technology or systems’ vendors goes into bankruptcy, ceases operations or fails to perform as promised, replacement services may not be readily available on a timely basis, at competitive rates or at all and any transition time to a new system may be significant.
In addition, our automated systems cannot be completely protected against events that are beyond our control, including natural disasters, cyber attacks or telecommunications failures. Substantial or sustained system failures could cause service delays or failures and result in our customers purchasing tickets from other airlines. We have implemented security measures and change control procedures and have disaster recovery plans; however, we cannot assure you that these measures are adequate to prevent disruptions. Disruption in, changes to or a breach of, these systems could result in a disruption to our business and the loss of important data. Moreover, in the event of system outages or interruptions, we may not be able to recover from our information technology and software providers all or any portion of the costs or business losses we may incur. Any of the foregoing could result in a material adverse effect on our business, results of operations and financial condition.

We are subject to cyber security risks and may incur increasing costs in an effort to minimize those risks.

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Our business employs systems and websites that allow for the secure storage and transmission of proprietary or confidential information regarding our customers, employees, suppliers and others, including personal identification information, credit card data and other confidential information. Security breaches could expose us to a risk of loss or misuse of this information, litigation and potential liability. Although we take steps to secure our management information systems, and although multiple auditors review and approve the security configurations and management processes of these systems, including our computer systems, intranet and internet sites, email and other telecommunications and data networks, the security measures we have implemented may not be effective, and our systems may be vulnerable to theft, loss, damage and interruption from a number of potential sources and events, including unauthorized access or security breaches, natural or man-made disasters, cyber attacks, computer viruses, power loss, or other disruptive events.  We may not have the resources or technical sophistication to anticipate or prevent rapidly evolving types of cyber attacks. Attacks may be targeted at us, our customers and suppliers, or others who have entrusted us with information. In addition, attacks not targeted at us, but targeted solely at suppliers, may cause disruption to our computer systems or a breach of the data that we maintain on customers, employees, suppliers and others.
Actual or anticipated attacks may cause us to incur increasing costs, including costs to deploy additional personnel and protection technologies, train employees and engage third-party experts and consultants, or costs incurred in connection with the notifications to employees, suppliers or the general public as part of our notification obligations to the various governments that govern our business. Advances in computer capabilities, new technological discoveries, or other developments may result in the breach or compromise of technology used by us to protect transaction or other data. In addition, data and security breaches can also occur as a result of non-technical issues, including breaches by us or by persons with whom we have commercial relationships that result in the unauthorized release of personal or confidential information. Our reputation, brand and financial condition could be adversely affected if, as a result of a significant cyber event or other security issues: our operations are disrupted or shut down; our confidential, proprietary information is stolen or disclosed; we incur costs or are required to pay fines in connection with stolen customer, employee or other confidential information; we must dedicate significant resources to system repairs or increase cyber security protection; or we otherwise incur significant litigation or other costs.
Our processing, storage, use and disclosure of personal data could give rise to liabilities as a result of governmental regulation.
In the processing of our customer transactions, we receive, process, transmit and store a large volume of identifiable personal data, including financial data such as credit card information. This data is increasingly subject to legislation and regulation, such as the Fair Accurate Credit Transparency Act and Payment Card Industry legislation, typically intended to protect the privacy of personal data that is collected, processed and transmitted. More generally, we rely on consumer confidence in the security of our system, including our website on which we sell the majority of our tickets. Our business, results of operations and financial condition could be adversely affected if we are unable to comply with existing privacy obligations or legislation or regulations are expanded to require changes in our business practices.
We may not be able to maintain or grow our non-ticket revenues.
Our business strategy includes expanding our portfolio of ancillary products and services. There can be no assurance that passengers will pay for additional ancillary products and services or that passengers will continue to choose to pay for the ancillary products and services we currently offer. Further, regulatory initiatives could adversely affect ancillary revenue opportunities. Failure to maintain our non-ticket revenues would have a material adverse effect on our results of operations and financial condition. Furthermore, if we are unable to maintain and grow our non-ticket revenues, we may not be able to execute our strategy to continue to lower base fares to address an underserved market. Please see “—Restrictions on or increased taxes applicable to charges for ancillary products and services paid by airline passengers and burdensome consumer protection regulations or laws could harm our business, results of operations and financial condition.”
Our inability to expand or operate reliably or efficiently out of our key airports where we maintain a large presence could have a material adverse effect on our business, results of operations and financial condition.
We are highly dependent on markets served from airports where we maintain a large presence. Our results of operations may be affected by actions taken by governmental or other agencies or authorities having jurisdiction over our operations at airports, including, but not limited to:
increases in airport rates and charges;
limitations on take-off and landing slots, airport gate capacity or other use of airport facilities;

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termination of our airport use agreements, some of which can be terminated by airport authorities with little notice to us;
increases in airport capacity that could facilitate increased competition;
international travel regulations such as customs and immigration;
increases in taxes;
changes in the law that affect the services that can be offered by airlines in particular markets and at particular airports;
restrictions on competitive practices;
the adoption of statutes or regulations that impact customer service standards, including security standards; and
the adoption of more restrictive locally-imposed noise regulations or curfews.
In general, any changes in airport operations could have a material adverse effect on our business, results of operations and financial condition.
We rely on third-party service providers to perform functions integral to our operations.
We have entered into agreements with third-party service providers to furnish certain facilities and services required for our operations, including ground handling, catering, passenger handling, engineering, maintenance, refueling, reservations and airport facilities as well as administrative and support services. We are likely to enter into similar service agreements in new markets we decide to enter, and there can be no assurance that we will be able to obtain the necessary services at acceptable rates.
Although we seek to monitor the performance of third parties that provide us with our reservation system, ground handling, catering, passenger handling, engineering, maintenance services, refueling and airport facilities, the efficiency, timeliness and quality of contract performance by third-party service providers are often beyond our control, and any failure by our service providers to perform their contracts may have an adverse impact on our business and operations. For example, in 2008, our call center provider went bankrupt. Though we were able to quickly switch to an alternative vendor, we experienced a significant business disruption during the transition period and a similar disruption could occur in the future if we changed call center providers or if an existing provider ceased to be able to serve us. We expect to be dependent on such third-party arrangements for the foreseeable future.
We rely on third-party distribution channels to distribute a portion of our airline tickets.
We rely on third-party distribution channels, including those provided by or through global distribution systems, or GDSs, conventional travel agents and online travel agents, or OTAs, to distribute a portion of our airline tickets, and we expect in the future to rely on these channels to an increasing extent to collect ancillary revenues. These distribution channels are more expensive and at present have less functionality in respect of ancillary revenues than those we operate ourselves, such as our call centers and our website. Certain of these distribution channels also effectively restrict the manner in which we distribute our products generally. To remain competitive, we will need to successfully manage our distribution costs and rights, and improve the functionality of third-party distribution channels, while maintaining an industry-competitive cost structure. Negotiations with key GDSs and OTAs designed to manage our costs, increase our distribution flexibility, and improve functionality could be contentious, could result in diminished or less favorable distribution of our tickets, and may not provide the functionality we require to maximize ancillary revenues. Any inability to manage our third-party distribution costs, rights and functionality at a competitive level or any material diminishment in the distribution of our tickets could have a material adverse effect on our competitive position and our results of operations. Moreover, our ability to compete in the markets we serve may be threatened by changes in technology or other factors that may make our existing third-party sales channels impractical, uncompetitive, or obsolete.
We rely on a single service provider to manage the majority of our fuel supply.
As of December 31, 2018, we had a single fuel service contract with World Fuel Services Corporation to manage the majority of the sourcing and contracting of our fuel supply. A failure by this provider to fulfill its obligations could have a material adverse effect on our business, results of operations and financial condition.
Our reputation and business could be materially adversely affected in the event of an emergency, accident or similar incident involving our aircraft.

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We are exposed to potential significant losses in the event that any of our aircraft is subject to an emergency, accident, terrorist incident or other similar incident, and significant costs related to passenger claims, repairs or replacement of a damaged aircraft and its temporary or permanent loss from service. There can be no assurance that we will not be affected by such events or that the amount of our insurance coverage will be adequate in the event such circumstances arise and any such event could cause a substantial increase in our insurance premiums. Please see “—Increases in insurance costs or significant reductions in coverage could have a material adverse effect on our business, financial condition and results of operations.” In addition, any future aircraft emergency, accident or similar incident, even if fully covered by insurance or even if it does not involve our airline, may create a public perception that our airline or the equipment we fly is less safe or reliable than other transportation alternatives, or could cause us to perform time consuming and costly inspections on our aircraft or engines which could have a material adverse effect on our business, results of operations and financial condition.
Negative publicity regarding our customer service or otherwise could have a material adverse effect on our business.
In the past, we have experienced a relatively high number of customer complaints related to, among other things, our customer service and reservations and ticketing systems. In particular, we generally experience a higher volume of complaints when we make changes to our unbundling policies, such as charging for baggage. In addition, in 2009, we entered into a consent order with the DOT for our procedures for bumping passengers from oversold flights and our handling of lost or damaged baggage. Under the consent order, we were assessed a civil penalty of $375,000, of which we were required to pay $215,000 based on an agreement with the DOT and not having similar violations in the year after the date of the consent order. Further, media reports about incidents on our aircraft unrelated to customer complaints could negatively impact our reputation and our operations. If we do not meet our customers' expectations with respect to reliability and service, customers could decide not to fly with us, which would materially adversely affect our business and reputation.
We depend on a limited number of suppliers for our aircraft and engines.
One of the elements of our business strategy is to save costs by operating a single-family aircraft fleet - currently Airbus A320-family, single-aisle aircraft, powered by engines manufactured by IAE and Pratt & Whitney. If any of Airbus, IAE, or Pratt & Whitney become unable to perform its contractual obligations, or if we are unable to acquire or lease aircraft or engines from these or other owners, operators or lessors on acceptable terms, we would have to find other suppliers for a similar type of aircraft or engine. If we have to lease or purchase aircraft from another supplier, we would lose the significant benefits we derive from our current single fleet composition. We may also incur substantial transition costs, including costs associated with retraining our employees, replacing our manuals and adapting our facilities and maintenance programs. Our operations could also be harmed by the failure or inability of aircraft, engine and parts suppliers to provide sufficient spare parts or related support services on a timely basis, particularly in connection with new-generation introductory technology. Our business would be significantly harmed if a design defect or mechanical problem with any of the types of aircraft, engines or components currently on order or that we operate were discovered that would halt or delay our aircraft delivery stream or that would ground any of our aircraft while the defect or problem was corrected, assuming it could be corrected at all. For example, during the fourth quarter of 2016, and continuing through early 2018, introductory issues with the new-generation PW1100G-JM engines, designed and manufactured by Pratt & Whitney, resulted in the intermittent grounding of certain of our A320neo aircraft. In February 2018, all five of our A320neo aircraft became fully operational and the aircraft continue to be in service. We continuously work with Pratt & Whitney to secure support and relief in connection with possible engine related operation disruptions. Due in part to issues involving the new engine, we have renegotiated certain aspects of our aircraft delivery schedule. We originally had four A320neos scheduled for delivery in 2018 of which two were converted to A320ceo aircraft, and delivered in 2017, and the remaining two were deferred until 2019. In January 2018, we also amended our 2019 order to convert five of our 2019 A320neo aircraft to A320ceo aircraft. We cannot be certain that the new generation PW1100G-JM issues will be corrected or if the defect will require the grounding of any of our A320neos. These types of events, if appropriate design or mechanical modifications cannot be adequately implemented, could materially adversely affect our business, results of operations and financial condition. Moreover, the use of our aircraft could be suspended or restricted by regulatory authorities in the event of actual or perceived mechanical or design problems. Our business would also be significantly harmed if the public began to avoid flying with us due to an adverse perception of the types of aircraft, engines or components that we operate stemming from safety concerns or other problems, whether real or perceived, or in the event of an accident involving those types of aircraft, engines or components. Carriers that operate a more diversified fleet are better positioned than we are to manage such events.
Reduction in demand for air transportation, or governmental reduction or limitation of operating capacity, in the domestic U.S., Caribbean or Latin American markets could harm our business, results of operations and financial condition.
A significant portion of our operations are conducted to and from the domestic U.S., Caribbean or Latin American markets. Our business, results of operations and financial condition could be harmed if we lost our authority to fly to these

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markets, by any circumstances causing a reduction in demand for air transportation, or by governmental reduction or limitation of operating capacity, in these markets, such as adverse changes in local economic or political conditions, negative public perception of these destinations, unfavorable weather conditions, public health concerns or terrorist related activities. Furthermore, our business could be harmed if jurisdictions that currently limit competition allow additional airlines to compete on routes we serve. Many of the countries we serve are experiencing either economic slowdowns or recessions, which may translate into a weakening of demand and could harm our business, results of operations and financial condition.
Increases in insurance costs or significant reductions in coverage could have a material adverse effect on our business, financial condition and results of operations.
We carry insurance for third-party liability, passenger liability, property damage and all-risk coverage for damage to our aircraft. As a result of the September 11, 2001 terrorist attacks, aviation insurers significantly reduced the amount of insurance coverage available to commercial air carriers for liability to persons other than employees or passengers for claims resulting from acts of terrorism, war or similar events (war risk insurance). Accordingly, our insurance costs increased significantly and our ability to continue to obtain certain types of insurance remains uncertain. While the price of commercial insurance has declined since the period immediately after the terrorist attacks, in the event commercial insurance carriers further reduce the amount of insurance coverage available to us, or significantly increase its cost, we would be adversely affected. We currently maintain commercial airline insurance with several underwriters. However, there can be no assurance that the amount of such coverage will not be changed, or that we will not bear substantial losses from accidents. We could incur substantial claims resulting from an accident in excess of related insurance coverage that could have a material adverse effect on our results of operations and financial condition. Renewing coverage may result in higher premiums and more restrictive terms. Our business, results of operations and financial condition could be materially adversely affected if we are unable to obtain adequate insurance.
Failure to comply with applicable environmental regulations could have a material adverse effect on our business, results of operations and financial condition.
We are subject to increasingly stringent federal, state, local and foreign laws, regulations and ordinances relating to the protection of the environment, including those relating to emissions to the air, discharges to surface and subsurface waters, safe drinking water and the management of hazardous substances, oils and waste materials. Compliance with all environmental laws and regulations can require significant expenditures and any future regulatory developments in the United States and abroad could adversely affect operations and increase operating costs in the airline industry. For example, climate change legislation was previously introduced in Congress and such legislation could be re-introduced in the future by Congress and state legislatures, and could contain provisions affecting the aviation industry, compliance with which could result in the creation of substantial additional costs to us. Similarly, the Environmental Protection Agency issued a rule that regulates larger emitters of greenhouse gases. Future operations and financial results may vary as a result of such regulations. Compliance with these regulations and new or existing regulations that may be applicable to us in the future could increase our cost base and could have a material adverse effect on our business, results of operations and financial condition.

There is also an increasing international focus on climate change and environmental regulation. Members of the International Civil Aviation Organization ("ICAO") have been negotiating a global agreement in greenhouse gas emissions for the aviation industry. In October 2016, the ICAO adopted the Carbon Offsetting and Reduction Scheme for International Aviation ("CORSIA"), which is a global, market-based emissions offset program designed to encourage carbon-neutral growth beyond 2020. Further, in June 2018 the ICAO adopted standards pertaining to the collection and sharing of information in international aviation emissions beginning in 2019. The CORSIA will increase operating costs for Spirit and other U.S. airlines that operate internationally. The CORSIA is expected to be implemented in phases, with information sharing beginning in 2019 and phase I beginning in 2021. Certain details are still being developed and the impact cannot be fully predicted. Compliance with CORSIA could significantly increase our operating costs beginning in 2019 and beyond. The potential impact of CORSIA or other emissions-related requirements on our costs will ultimately depend on a number of factors, including baseline emissions, the price of emission allowances or offsets that we would need to acquire, the efficiency of our fleet and the number of flights subject to these requirements. These costs have not been completely defined and could fluctuate.
Governmental authorities in several U.S. and foreign cities are also considering or have already implemented aircraft noise reduction programs, including the imposition of nighttime curfews and limitations on daytime take-offs and landings. We have been able to accommodate local noise restrictions imposed to date, but our operations could be adversely affected if locally-imposed regulations become more restrictive or widespread.

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If we are unable to attract and retain qualified personnel or fail to maintain our company culture, our business, results of operations and financial condition could be harmed.
Our business is labor intensive. We require large numbers of pilots, flight attendants, maintenance technicians and other personnel. The airline industry has from time to time experienced a shortage of qualified personnel, particularly with respect to pilots and maintenance technicians. In addition, we may face high employee turnover. We may be required to increase wages and/or benefits in order to attract and retain qualified personnel. If we are unable to hire, train and retain qualified employees, our business could be harmed and we may be unable to implement our growth plans.
In addition, as we hire more people and grow, we believe it may be increasingly challenging to continue to hire people who will maintain our company culture. Our company culture, which we believe is one of our competitive strengths, is important to providing high-quality customer service and having a productive, accountable workforce that helps keep our costs low. As we continue to grow, we may be unable to identify, hire or retain enough people who meet the above criteria, including those in management or other key positions. Our company culture could otherwise be adversely affected by our growing operations and geographic diversity. If we fail to maintain the strength of our company culture, our competitive ability and our business, results of operations and financial condition could be harmed.
Our business, results of operations and financial condition could be materially adversely affected if we lose the services of our key personnel.
Our success depends to a significant extent upon the efforts and abilities of our senior management team and key financial and operating personnel. In particular, we depend on the services of our senior management team. Competition for highly qualified personnel is intense, and the loss of any executive officer, senior manager, or other key employee without adequate replacement or the inability to attract new qualified personnel could have a material adverse effect on our business, results of operations and financial condition. We do not maintain key-person life insurance on our management team.
The requirements of being a public company may strain our resources, divert management’s attention and affect our ability to attract and retain qualified board members.
As a public company, we incur significant legal, accounting and other expenses, including costs associated with public company reporting requirements. We also have incurred and will continue to incur costs associated with the Sarbanes-Oxley Act of 2002, as amended, the Dodd-Frank Wall Street Reform and Consumer Protection Act and related rules implemented or to be implemented by the SEC and the New York Stock Exchange. The expenses incurred by public companies generally for reporting and corporate governance purposes have been increasing. We expect these rules and regulations to increase our legal and financial compliance costs and to make some activities more time-consuming and costly. These laws and regulations could also make it more difficult or costly for us to obtain certain types of insurance, including director and officer liability insurance, and we may be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. These laws and regulations could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, our board committees, or as our executive officers and may divert management’s attention. Furthermore, if we are unable to satisfy our obligations as a public company, we could be subject to delisting of our common stock, fines, sanctions and other regulatory action and potentially civil litigation.
We are required to assess our internal control over financial reporting on an annual basis, and any future adverse findings from such assessment could result in a loss of investor confidence in our financial reports, significant expenses to remediate any internal control deficiencies, and ultimately have an adverse effect on the market price of our common stock.
Pursuant to Section 404 of the Sarbanes-Oxley Act of 2002, as amended, our management is required to report on, and our independent registered public accounting firm is required to attest to, the effectiveness of our internal control over financial reporting. The rules governing the standards that must be met for management to assess our internal control over financial reporting are complex and require significant documentation, testing and possible remediation. Annually, we perform activities that include reviewing, documenting and testing our internal control over financial reporting. During the performance of these activities, we may encounter problems or delays in completing the implementation of any changes necessary to make a favorable assessment of our internal control over financial reporting. In connection with the attestation process by our independent registered public accounting firm, we may encounter problems or delays in completing the implementation of any requested improvements and receiving a favorable attestation. In addition, if we fail to maintain the adequacy of our internal control over financial reporting we will not be able to conclude on an ongoing basis that we have effective internal control over financial reporting in accordance with Section 404. If we fail to achieve and maintain an effective internal control environment, we could suffer material misstatements in our financial statements and fail to meet our reporting obligations, which would likely cause investors to lose confidence in our reported financial information. This could harm our operating results and lead to a decline in our stock price. Additionally, ineffective internal control over financial reporting could expose

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us to increased risk of fraud or misuse of corporate assets and subject us to potential delisting from the New York Stock Exchange, regulatory investigations, civil or criminal sanctions and class action litigation.
The market price of our common stock may be volatile, which could cause the value of an investment in our stock to decline.
The market price of our common stock may fluctuate substantially due to a variety of factors, many of which are beyond our control, including:
announcements concerning our competitors, the airline industry or the economy in general;
strategic actions by us or our competitors, such as acquisitions or restructurings;
increased price competition;
media reports and publications about the safety of our aircraft or the aircraft type we operate;
new regulatory pronouncements and changes in regulatory guidelines;
changes in the price of aircraft fuel;
announcements concerning the availability of the type of aircraft we use;
general and industry-specific economic conditions;
changes in financial estimates or recommendations by securities analysts or failure to meet analysts’ performance expectations;
sales of our common stock or other actions by investors with significant shareholdings;
trading strategies related to changes in fuel or oil prices; and
general market, political and economic conditions.
The stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of particular companies. These types of broad market fluctuations may adversely affect the trading price of our common stock.
In the past, stockholders have sometimes instituted securities class action litigation against companies following periods of volatility in the market price of their securities. Any similar litigation against us could result in substantial costs, divert management’s attention and resources and harm our business or results of operations.
If securities or industry analysts do not publish research or reports about our business, or publish negative reports about our business, our stock price and trading volume could decline.
The trading market for our common stock depends in part on the research and reports that securities or industry analysts publish about us or our business. If one or more of the analysts who cover us downgrade our stock or publish inaccurate or unfavorable research about our business, our stock price would likely decline. If one or more of these analysts cease coverage of our company or fail to publish reports on us regularly, demand for our stock could decrease, which might cause our stock price and trading volume to decline.
Our anti-takeover provisions may delay or prevent a change of control, which could adversely affect the price of our common stock.
Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that may make it difficult to remove our board of directors and management and may discourage or delay “change of control” transactions, which could adversely affect the price of our common stock. These provisions include, among others:
our board of directors is divided into three classes, with each class serving for a staggered three-year term, which prevents stockholders from electing an entirely new board of directors at an annual meeting;
actions to be taken by our stockholders may only be effected at an annual or special meeting of our stockholders and not by written consent;

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special meetings of our stockholders can be called only by the Chairman of the Board or by our corporate secretary at the direction of our board of directors;
advance notice procedures that stockholders must comply with in order to nominate candidates to our board of directors and propose matters to be brought before an annual meeting of our stockholders may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of our company; and
our board of directors may, without stockholder approval, issue series of preferred stock, or rights to acquire preferred stock, that could dilute the interest of, or impair the voting power of, holders of our common stock or could also be used as a method of discouraging, delaying or preventing a change of control.
Our corporate charter and bylaws include provisions limiting voting by non-U.S. citizens and specifying an exclusive forum for stockholder disputes.
To comply with restrictions imposed by federal law on foreign ownership of U.S. airlines, our amended and restated certificate of incorporation and amended and restated bylaws restrict voting of shares of our common stock by non-U.S. citizens. The restrictions imposed by federal law currently require that no more than 25% of our stock be voted, directly or indirectly, by persons who are not U.S. citizens, and that our president and at least two-thirds of the members of our board of directors and senior management be U.S. citizens. Our amended and restated bylaws provide that the failure of non-U.S. citizens to register their shares on a separate stock record, which we refer to as the “foreign stock record,” would result in a suspension of their voting rights in the event that the aggregate foreign ownership of the outstanding common stock exceeds the foreign ownership restrictions imposed by federal law.
Our amended and restated bylaws further provide that no shares of our common stock will be registered on the foreign stock record if the amount so registered would exceed the foreign ownership restrictions imposed by federal law. If it is determined that the amount registered in the foreign stock record exceeds the foreign ownership restrictions imposed by federal law, shares will be removed from the foreign stock record in reverse chronological order based on the date of registration therein, until the number of shares registered therein does not exceed the foreign ownership restrictions imposed by federal law. As of December 31, 2018, we believe we were in compliance with the foreign ownership rules.
As of December 31, 2018, there are no shares of non-voting common stock outstanding. When shares of non-voting common stock are outstanding, the holders of such stock may convert such shares, on a share-for-share basis, in the order reflected on our foreign stock record as shares of common stock are sold or otherwise transferred by non-U.S. citizens to U.S. citizens.
Our amended and restated certificate of incorporation also specifies that the Court of Chancery of the State of Delaware shall be the exclusive forum for substantially all disputes between us and our stockholders.
We do not intend to pay cash dividends for the foreseeable future.
We have never declared or paid cash dividends on our common stock. We currently intend to retain our future earnings, if any, to finance the further development and expansion of our business and fund share repurchases under programs approved by our Board of Directors. We do not intend to pay cash dividends in the foreseeable future. Any future determination to pay dividends will be at the discretion of our board of directors and will depend on our financial condition, results of operations, capital requirements, restrictions contained in current or future financing instruments, business prospects and such other factors as our Board of Directors deems relevant. The timing of any share repurchases under share repurchase programs will depend upon market conditions, our capital allocation strategy and other factors.

30



ITEM 1B.    UNRESOLVED STAFF COMMENTS
None.
ITEM 2.    PROPERTIES
Aircraft
As of December 31, 2018, we operated a fleet of 128 aircraft as detailed in the following table:
Aircraft Type
Seats
Average Age (years)
Number of Aircraft
Number Owned
Number Leased
A319
145
11.9
31
22
9
A320ceo
182
4.2
60
30
30
A320neo
182
1.5
7
7
A321
228
2.0
30
30
 
 
5.4
128
82
46
As of December 31, 2018, our firm aircraft orders consisted of 50 A320 family aircraft with Airbus (2 A320ceos and 43 A320neos with Airbus and an additional 5 direct operating leases for A320neos with a third-party lessor). As of December 31, 2018, our future fleet plan, net of contractual lease returns, is illustrated in the table below.
Aircraft Type
2019
2020
2021
2022
2023
A319
31
31
30
26
26
A320ceo
62
62
62
58
53
A320neo
21
37
55
55
55
A321
30
30
30
30
30
Total Aircraft
144
160
177
169
164
Note 1: Actual fleet count may differ depending on future fleet decisions, including actual lease returns.
During the first quarter of 2018, we negotiated revisions to our A320 aircraft order. We originally had 14 A320neo aircraft scheduled for delivery in 2019. Pursuant to the revision, 5 of the 14 scheduled A320neo aircraft were converted to A320ceo aircraft. Of these five aircraft, three were delivered in the fourth quarter of 2018 and the remaining two are scheduled to be delivered in 2019. During the third quarter of 2018, we entered into operating lease agreements for the lease of 7 A320neos of which 2 were delivered in the fourth quarter of 2018 and the remaining 5 are scheduled to be delivered in 2019. We also have two spare engine orders for V2500 SelectTwo engines with IAE and eight spare engine orders for PurePower PW 1100G-JM engines with Pratt & Whitney. Spare engines are scheduled for delivery from 2019 through 2024.
Ground Facilities    
We lease all of our facilities at each of the airports we serve, with the exception of our newly constructed aircraft hangar in Detroit, which we own. Our leases for terminal passenger service facilities, which include ticket counter and gate space, operations support areas and baggage service offices, generally have a term ranging from month-to-month to 16 years, and contain provisions for periodic adjustments of lease rates. We also are responsible for maintenance, insurance and other facility-related expenses and services. We also have entered into use agreements at the airports we serve that provide for the non-exclusive use of runways, taxiways and other airfield facilities. Landing fees paid under these agreements are based on the number of landings and weight of the aircraft.
As of December 31, 2018, Ft. Lauderdale/Hollywood International Airport (FLL) remained our single largest airport served, with approximately 25% of our capacity operating from FLL during 2018. We operate primarily out of Terminal 4 at FLL, the international terminal. We currently use up to ten gates simultaneously at Terminal 3 and Terminal 4. We have preferential access to six of the Terminal 4 gates, preferential access to two of the Terminal 3 gates, common use access to the remaining four Terminal 4 gates, and access to other Terminal 3 gates. FLL is in the middle of a concourse replacement and expansion project, which will expand the number of gates at Terminal 4 from 10 to 14. Other airports through which we conduct significant operations include McCarran International Airport (LAS), Orlando International Airport (MCO), Detroit

31



Metropolitan Wayne County Airport (DTW), Chicago O'Hare International Airport (ORD), Dallas/Fort Worth International Airport (DFW), and Baltimore/Washington International Airport (BWI).
Our largest maintenance facility is a hangar currently located at DTW. This hangar is owned and operated on leased land. The lease with the airport authority expires in September 2032. We also conduct additional maintenance operations in leased facilities in Fort Lauderdale, Florida; Chicago, Illinois; Atlantic City, New Jersey; Dallas, Texas; Houston, Texas; Las Vegas, Nevada; Orlando, Florida; Atlanta, Georgia; Myrtle Beach, South Carolina; Fort Myers, Florida; and Philadelphia, Pennsylvania.
Our principal executive offices and headquarters are located in a leased facility at 2800 Executive Way, Miramar, Florida 33025, consisting of approximately 56,000 square feet. The lease for this facility expires in January 2025. In January 2014, we expanded our principal executive offices and headquarters by leasing an additional facility located at 2844 Corporate Way, Miramar, Florida 33025, consisting of approximately 15,000 square feet. The lease for this facility expires in January 2025. In March 2018 we added approximately 26,000 square feet of office space at 2877-2899 N Commerce Parkway, Miramar, FL 33025 to further support the corporate headquarters. The lease on this space expires on June 30, 2021. We also have a training center located in a leased facility at 1050 Lee Wagener Boulevard, Fort Lauderdale, Florida 33315, consisting of approximately 12,000 square feet, under a lease that expires in January 2020.
ITEM 3.    LEGAL PROCEEDINGS
We are subject to commercial litigation claims and to administrative and regulatory proceedings and reviews that may be asserted or maintained from time to time. We believe the ultimate outcome of pending lawsuits, proceedings and reviews will not, individually or in the aggregate, have a material adverse effect on our financial position, liquidity, or results of operations.
ITEM 4.    MINE SAFETY DISCLOSURES
Not applicable.

32



PART II
ITEM 5.    MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES
Market Price of our common stock
Our common stock is listed and traded on the NYSE under the symbol "SAVE," as of December 28, 2017. Prior to this date, our stock traded on the NASDAQ under the symbol "SAVE." The following table shows, for the periods indicated, the high and low closing per share sales prices for our common stock.
 
High
 
Low
Fiscal year ended December 31, 2017
 
 
 
First Quarter
$
58.10

 
$
49.53

Second Quarter
59.74

 
50.90

Third Quarter
53.46

 
32.09

Fourth Quarter
45.30

 
33.47

Fiscal year ended December 31, 2018
 
 
 
First Quarter
$
48.26

 
$
36.99

Second Quarter
39.61

 
34.98

Third Quarter
49.27

 
36.13

Fourth Quarter
64.59

 
43.83

As of February 1, 2019, there were approximately 110 holders of record of our common stock. Because many of our shares are held by brokers and other institutions on behalf of stockholders, we are unable to estimate the total number of stockholders represented by the holders.
The information under the caption “Equity Compensation Plan Information” in our 2019 Proxy Statement is incorporated herein by reference.
Dividend Policy
We have never declared or paid, and do not anticipate declaring or paying, any cash dividends on our common stock. Any future determination as to the declaration and payment of dividends, if any, will be at the discretion of our board of directors and will depend on then existing conditions, including our financial condition, operating results, contractual restrictions, capital requirements, business prospects and other factors our board of directors may deem relevant.

33



Our Repurchases of Equity Securities
The following table reflects our repurchases of our common stock during the fourth quarter of 2018. Repurchases of equity securities during the period include repurchases made from employees who received restricted stock. All employee stock repurchases were made at the election of each employee pursuant to an offer to repurchase by us. In each case, the shares repurchased constituted the portion of vested shares necessary to satisfy tax withholding requirements.
ISSUER PURCHASES OF EQUITY SECURITIES
 
 
 
 
 
 
 
 
 
Period
 
Total Number of Shares Purchased
 
Average Price Paid per Share
 
Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs
 
Approximate Dollar Value of Shares that May Yet be Purchased Under Plans or Programs
October 1-31, 2018
 
196

 
$
48.84

 

 
$

November 1-30, 2018
 

 

 

 

December 1-31, 2018
 
114

 
60.40

 

 

Total
 
310

 
$
53.09

 

 
 
During the first three quarters of 2018, we repurchased 28 thousand shares for a total of $1.1 million. Repurchases of equity securities during this period include repurchases made from employees who received restricted stock awards.
During 2018, there were no open market repurchases made under our stock repurchase program that expired on October 25, 2018. During 2017, we repurchased 1.2 million shares for $44.9 million under our open market stock repurchase program. During the year ended December 31, 2018, we had no treasury share retirements. During the year ended December 31, 2017, we retired 3.9 million treasury shares in a total aggregate amount of $199.4 million.




34



Stock Performance Graph
The following graph compares the cumulative total stockholder return on our common stock with the cumulative total return on the NASDAQ Composite Index and the NYSE ARCA Airline Index for the period beginning on December 31, 2013 and ending on December 31, 2018. The graph assumes an investment of $100 in our stock and the two indices, respectively, on December 31, 2013, and further assumes the reinvestment of all dividends. Stock price performance, presented for the period from December 31, 2013 to December 31, 2018, is not necessarily indicative of future results.
396731595_chart-6624e3b125d08003593.jpg
 
12/31/2013
12/31/2014
12/31/2015
12/31/2016
12/31/2017
12/31/2018
Spirit
$
100.00

$
166.44

$
87.76

$
127.42

$
98.77

$
127.55

NYSE ARCA Airline Index
$
100.00

$
150.20

$
127.27

$
163.58

$
173.69

$
136.52

NASDAQ Composite Index
$
100.00

$
114.83

$
122.99

$
134.02

$
173.86

$
168.98


35



ITEM 6.    SELECTED FINANCIAL DATA
You should read the following selected historical financial and operating data below in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the financial statements, related notes and other financial information included in this annual report. The selected financial data in this section are not intended to replace the financial statements and are qualified in their entirety by the financial statements and related notes included in this annual report.
We derived the selected statements of operations data for the years ended December 31, 2018, 2017 and 2016 and the balance sheet data as of December 31, 2018 and 2017 from our audited financial statements included in this annual report. We derived the selected statements of operations data for the years ended December 31, 2015 and 2014 and the balance sheet data as of December 31, 2016, 2015 and 2014 from our audited financial statements not included in this annual report. Our historical results are not necessarily indicative of the results to be expected in the future.
 
Year Ended December 31,
 
2018
 
2017
 
2016
 
2015
 
2014
 
(in thousands, except share and per-share data)
Operating revenues:
 
 
 
 
 
 
 
 
 
Passenger (1)
$
3,260,015

 
$
2,572,887

 
$
2,257,801

 
$
1,169,338

 
$
1,144,972

Other (1)
63,019

 
70,665

 
62,220

 
972,125

 
786,608

Total operating revenue
3,323,034

 
2,643,552

 
2,320,021

 
2,141,463

 
1,931,580

Operating expenses:
 
 
 
 
 
 
 
 
 
Aircraft fuel (2)
939,324

 
615,581

 
447,553

 
461,447

 
612,909

Salaries, wages and benefits
719,635

 
527,959

 
472,471

 
377,508

 
313,409

Landing fees and other rents
214,677

 
180,655

 
151,679

 
131,077

 
105,115

Aircraft rent
177,641

 
205,852

 
201,675

 
211,531

 
195,827

Depreciation and amortization
176,727

 
140,152

 
101,136

 
73,908

 
46,971

Distribution
137,001

 
113,472

 
96,895

 
86,576

 
74,823

Maintenance, materials and repairs
129,078

 
110,439

 
98,587

 
80,448

 
73,956

Special charges (3)
88,921

 
12,629

 
37,189

 
673

 
45

Loss on disposal of assets
9,580

 
4,168

 
4,187

 
1,604

 
3,008

Other operating
379,536

 
347,820

 
267,191

 
207,569

 
150,254

Total operating expenses
2,972,120

 
2,258,727

 
1,878,563

 
1,632,341

 
1,576,317

Operating income
350,914

 
384,825

 
441,458

 
509,122

 
355,263

Other (income) expense:
 
 
 
 
 
 
 
 
 
Interest expense (4)
83,777

 
57,302

 
41,654

 
20,382

 
2,747

Capitalized interest (5)
(9,841
)
 
(13,793
)
 
(12,705
)
 
(11,553
)
 
(2,747
)
Interest income
(19,107
)
 
(8,736
)
 
(5,276
)
 
(2,125
)
 
(336
)
Other expense
752

 
366

 
528

 
15

 
2,605

Special charges, non-operating (6)
90,357









Total other expense (income)
145,938

 
35,139

 
24,201

 
6,719

 
2,269

Income before income taxes
204,976

 
349,686

 
417,257

 
502,403

 
352,994

Provision (benefit) for income taxes (7)
49,227

 
(65,836
)
 
153,774

 
185,183

 
127,530

Net income
$
155,749

 
$
415,522

 
$
263,483

 
$
317,220

 
$
225,464

Earnings Per Share:
 
 
 
 
 
 
 
 
 
Basic
$
2.28

 
$
6.00

 
$
3.75

 
$
4.39

 
$
3.10

Diluted
$
2.28

 
$
5.99

 
$
3.74

 
$
4.38

 
$
3.08

Weighted average shares outstanding:
 
 
 
 
 
 
 
 
 
Basic
68,248,931

 
69,220,750

 
70,343,935

 
72,207,725

 
72,738,961

Diluted
68,430,832

 
69,376,930

 
70,507,596

 
72,426,060

 
73,293,869

 
(1)
Amounts prior to 2016 do not reflect the adoption of ASU No. 2014-09 (ASU 2014-09), "Revenue from Contracts with Customers," completed in the first quarter of 2018. Refer to “Notes to the Financial Statements—2, Recent Accounting Developments" for information regarding the Company's adoption of ASU 2014-09.
(2)
Aircraft fuel expense is the sum of (i) “into-plane fuel cost,” which includes the cost of jet fuel and certain other charges such as fuel taxes and oil, (ii) realized gains and losses related to fuel derivative contracts, if any, and (iii) unrealized gains and losses related to fuel derivative contracts, if any. The following table summarizes the components of aircraft fuel expense for the periods presented:

36



 
Year Ended December 31,

2018

2017

2016

2015

2014

(in thousands)
Into-plane fuel cost
$
939,324


$
615,581


$
447,553


$
454,747


$
608,033

Realized losses (gains) related to fuel derivatives contracts, net






10,580


995

Unrealized losses (gains) related to fuel derivative contracts, net






(3,880
)

3,881

Aircraft fuel expense
$
939,324


$
615,581


$
447,553


$
461,447


$
612,909


(3)
Special charges include: (i) for 2014, $0.1 million in costs related to the DCA exit; (ii) for 2015, $0.7 million related to restructuring charges for outsourcing of ramps and passenger services; (iii) for 2016, $37.2 million related to lease termination charges recognized in connection with the purchase of 7 aircraft formerly financed under operating lease agreements; (iv) for 2017, $12.6 million related to lease termination charges recognized in connection with the purchase of one engine and one aircraft formerly financed under operating lease agreements; (v) for 2018, $88.7 million related to the ratification incentive payment made in connection with the new collective bargaining agreement with our pilots. Please see "Notes to Financial Statements—5. Special Charges" for further discussion.
(4)
Interest expense in 2014 primarily relates to interest related to the long-term debt, commitment fees and underpayment of Federal Excise Tax for fuel purchases during the period between July 1, 2009 and August 31, 2014. Interest expense in 2015, 2016, 2017 and 2018 primarily relates to interest related to financing of purchasing aircraft.
(5)
Interest attributable to funds used to finance the acquisition of new aircraft, including PDPs is capitalized as an additional cost of the related asset. In 2015, 2016, 2017 and 2018, capitalized interest primarily represents interest related to the financing of purchased aircraft.
(6)
In 2018, special charges, non-operating represents interest related to an aircraft purchase agreement for the acquisition of 14 A319 aircraft previously operated under operating leases. The contract was deemed a lease modification which resulted in a change of classification from operating leases to capital leases. Please see "Notes to Financial Statements—5. Special Charges" for further discussion.
(7)
During the twelve months ended December 31, 2017, we recorded a non-recurring income tax benefit of $196.7 million ($2.84 and $2.84 per basic and diluted share, respectively) due to the enactment of the Tax Cuts and Jobs Act of 2017.

The following table presents balance sheet data for the periods presented:
 
As of December 31,
 
2018
 
2017
 
2016
 
2015
 
2014
 Balance Sheet Data:
(in thousands)
Cash and cash equivalents
$
1,004,733

 
$
800,849

 
$
700,900

 
$
803,632

 
$
632,784

Short-term investment securities
102,789


100,937


100,155





Total assets (8) (9)
5,165,457

 
4,145,800

 
3,153,629

 
2,530,545

 
1,592,753

Long-term debt and capital leases, including current portion
2,188,331

 
1,502,928

 
981,713

 
646,330

 
145,663

Stockholders' equity (9)
1,928,504

 
1,762,574

 
1,385,184

 
1,225,310

 
1,003,075


(8)    Prior period amounts have been reclassified to conform to ASU No. 2015-17 (ASU 2015-17), "Income Taxes" issued in November 2015.
(9)
Amounts prior to 2016 do not reflect the adoption of ASU No. 2014-09 (ASU 2014-09), "Revenue from Contracts with Customers," completed in the first quarter of 2018. Refer to “Notes to the Financial Statements—2, Recent Accounting Developments" for information regarding the Company's adoption of ASU 2014-09.



37




 
 
OPERATING STATISTICS
 
Year Ended December 31,

2018

2017

2016

2015

2014
Operating Statistics (unaudited) (A)









Average aircraft
118.9


103.6


86.2


72.7


57.7

Aircraft at end of period
128


112


95


79


65

Average daily aircraft utilization (hours)
12.1


11.6


12.4


12.7


12.7

Average stage length (miles)
1,032


999


979


987


980

Block hours
526,343


438,728


389,914


337,956


267,305

Departures
192,845


165,449


149,514


128,902


102,594

Passenger flight segments (thousands)
29,312


24,183


21,618


17,921


14,294

Revenue passenger miles (RPMs) (thousands)
30,623,379


24,605,512


21,581,611


17,995,311


14,159,860

Available seat miles (ASMs) (thousands)
36,502,982


29,592,819


25,494,645


21,246,156


16,340,142

Load factor (%)
83.9


83.1


84.7


84.7


86.7

Fare revenue per passenger flight segment ($)
58.14


56.38


55.42


65.25


80.11

Non-ticket revenue per passenger flight segment ($)
55.23


52.94


51.90


54.24


55.03

Total revenue per passenger segment ($)
113.37


109.32


107.32


119.49


135.14

Average yield (cents)
10.85


10.74


10.75


11.90


13.64

Total operating revenue per ASM (TRASM) (cents)
9.10


8.93


9.10


10.08


11.82

CASM (cents)
8.14


7.63


7.37


7.68


9.65

Adjusted CASM (cents) (B)
7.87


7.59


7.21


7.69


9.55

Adjusted CASM ex fuel (cents) (C)
5.30


5.51


5.45


5.50


5.88

Fuel gallons consumed (thousands)
412,256


343,709


302,781


255,008


200,498

Average economic fuel cost per gallon ($)
2.28


1.79


1.48


1.82


2.99

 
(A)
See “Glossary of Airline Terms” elsewhere in this annual report for definitions of terms used in this table.
(B)
Reconciliation of CASM to Adjusted CASM:
 
Year Ended December 31,
2018
 
2017
 
2016
 
2015
 
2014
(in millions)
 
Per ASM
 
(in millions)
 
Per ASM
 
(in millions)
 
Per ASM
 
(in millions)
 
Per ASM
 
(in millions)
 
Per ASM
CASM (cents)
 
 
8.14

 
 
 
7.63

 
 
 
7.37

 
 
 
7.68

 
 
 
9.65

Less:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Unrealized losses (gains) related to fuel derivative contracts
$

 

 
$

 

 
$

 

 
$
(3.9
)
 
(0.02
)
 
$
3.9

 
0.02

Loss on disposal of assets
9.6

 
0.03

 
4.2

 
0.01

 
4.2

 
0.02

 
1.6

 
0.01

 
3.0

 
0.02

Special charges
88.9

 
0.24

 
12.6

 
0.04

 
37.2

 
0.15

 
0.7

 

 

 

Out of period fuel excise tax

 

 

 

 

 

 

 

 
9.3

 
0.06

Supplemental rent adjustment for liabilities accrued in prior years that are no longer probable

 

 
(4.1
)
 
(0.01
)
 

 

 

 

 

 

Adjusted CASM (cents)
 
 
7.87

 
 
 
7.59

 
 
 
7.21

 
 
 
7.69

 
 
 
9.55


(C)
Excludes aircraft fuel expense, loss on disposal of assets, special charges and supplemental rent adjustment for liabilities accrued in prior years that are no longer probable.

38



ITEM 7.    MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
You should read the following discussion of our financial condition and results of operations in conjunction with the financial statements and the notes thereto included elsewhere in this annual report.

2018 Year in Review
The year 2018 marks our twelfth consecutive year of profitability. In 2018, we increased our capacity by 23.4%, as we grew our fleet of Airbus single-aisle aircraft from 112 to 128 aircraft, launched service to 50 new markets and added 9 new destinations: Cap-Haïtien, Haiti; St. Croix, U.S. Virgin Islands; Greensboro, North Carolina; Asheville, North Carolina; Jacksonville, Florida; Columbus, Ohio; Guayaquil, Ecuador; Cali, Colombia; Richmond, Virginia.
During 2018, we earned net income of $155.7 million ($2.28 per share, diluted), compared to net income of $415.5 million ($5.99 per share, diluted) in 2017. The decrease in earnings was primarily driven by a few non-recurring items recorded in 2017 and 2018. During 2018, the Company recorded $90.4 million in special charges, non-operating and $88.9 million in special charges, operating. Refer to “Notes to the Financial Statements—5. Special Charges" for additional information. Also contributing to the decrease in earnings year over year was a non-recurring income tax benefit of $196.7 million booked in 2017 due to the enactment of the Tax Cuts and Jobs Act. In addition, aircraft fuel expense increased by 52.6%, year over year, due to an increase in both fuel price per gallon and gallons consumed. These decreases in earnings were partially offset by a 24.5% increase in our traffic and a 1.0% increase in average yield, year over year.
For the year ended December 31, 2018, we achieved an operating profit margin of 10.6% on $3,323.0 million in operating revenues. Our traffic grew by 24.5% as we continued to address our value-conscious customers with ultra-low fares. Our operating yield increased by 1.0%, year over year, as a result of our strategic network re-orientation, improved yield management processes and non-ticket revenue initiatives. TRASM in 2018 was 9.10 cents, an increase of 1.9% compared to the prior year. Total revenue per passenger flight segment increased 3.7%, year over year, from $109.32 to $113.37 driven by a 4.3% increase in non-ticket revenue per passenger flight segment and a 3.1% increase in fare revenue per passenger flight segment, as compared to the prior year. The increase in non-ticket revenue per passenger flight segment was primarily attributable to higher bag revenue, passenger usage fee, and seat revenue per flight segment, as compared to the prior year.
Our operating cost structure is a primary area of focus and is at the core of our ULCC business model. Our unit operating costs continue to be among the lowest of any airline in the United States. During 2018, our adjusted CASM ex-fuel decreased by 3.8% to 5.30 cents. The decrease on a per-ASM basis was primarily due to decreases in aircraft rent expense per ASM and other operating expense per ASM. Operating expense per ASM was lower, year over year, mostly due to improved operational performance in 2018.
During 2018, we took delivery of 14 new aircraft financed under secured debt arrangements, 2 aircraft financed under operating leases, and purchased 14 previously leased aircraft. In addition, we took delivery of 10 engines through cash purchases and sold 6 engines. We also took delivery of 1 engine financed under an operating lease. As of December 31, 2018, our 128 Airbus A320-family aircraft fleet was comprised of 31 A319s, 60 A320ceos, 7 A320neos and 30 A321ceos of which 60 aircraft are financed through secured debt, 46 are financed under operating leases and 22 are unencumbered. As of December 31, 2018, our aircraft orders consisted of 50 A320 family aircraft scheduled for delivery from 2019 through 2021.
Operating Revenues
Our operating revenues are comprised of passenger revenues and other revenues.
Passenger revenues

Fare revenues. Tickets sold are initially deferred within air traffic liability on the Company's balance sheet. Passenger fare revenues are recognized at time of departure when transportation is provided. All tickets sold by the Company are nonrefundable. An unused ticket expires at the date of scheduled travel and is recognized as revenue at the date of scheduled travel. Passenger revenues reported prior to the adoption of ASU 2014-09 are now reported as fare revenues within passenger revenues in the Company's disaggregated revenue table within “Notes to the Financial Statements— 4, Revenue Disaggregation."
Non-fare revenues. Our most significant non-fare revenues include revenues generated from air travel-related services paid for baggage, passenger usage fees, advance seat selection, itinerary changes, and loyalty programs. The adoption of ASU

39



2014-09 impacted the classification of these ancillary items since they are deemed part of the single performance obligation of providing passenger transportation. These ancillary items are now recognized in non-fare revenues within passenger revenues in the Company's disaggregated revenue table within “Notes to the Financial Statements— 4, Revenue Disaggregation." Passenger non-fare revenues are recognized at time of departure when transportation is provided.
Passenger revenues are recognized once the related flight departs. Accordingly, the value of tickets and non-fare revenues sold in advance of travel is included under our current liabilities as “air traffic liability,” or ATL, until the related air travel is provided. Revenue generated from the FREE SPIRIT credit card affinity program are recognized in accordance with the criteria as set forth in Accounting Standards Update ASU 2014-09. Please see “—Critical Accounting Policies and Estimates—Frequent Flyer Program.”

Other revenues

Other revenues primarily consist of the marketing component of the sale of frequent flyer miles to our credit card partner and commissions revenue from the sale of various items such as hotels and rental cars.

Substantially all of our revenues are denominated in U.S. dollars. We recognize revenues net of certain taxes and airport passenger fees, which are collected by us on behalf of airports and governmental agencies and remitted to the applicable governmental entity or airport on a periodic basis. These taxes and fees include U.S. federal transportation taxes, federal security charges, airport passenger facility charges and foreign arrival and departure taxes. These items are collected from customers at the time they purchase their tickets, but are not included in our revenues. Upon collection from the customer, we record a liability within other current liabilities on our balance sheets and relieve the liability when payments are remitted to the applicable governmental agency or airport.

Operating Expenses
Our operating expenses consist of the following line items.
Aircraft Fuel. Aircraft fuel expense includes the cost of jet fuel, related federal taxes, fueling into-plane fees and transportation fees. It also includes realized and unrealized gains and losses arising from activity on our fuel derivatives, if any. Our fuel derivatives, if any, generally consist of United States Gulf Coast jet fuel swaps ("jet fuel swaps") and United States Gulf Coast jet fuel options ("jet fuel options").
Salaries, Wages and Benefits. Salaries, wages and benefits expense includes the salaries, hourly wages, bonuses and equity compensation paid to employees for their services, as well as the related expenses associated with employee benefit plans and employer payroll taxes.
Landing Fees and Other Rents. Landing fees and other rents include both fixed and variable facilities expenses, such as the fees charged by airports for the use or lease of airport facilities, overfly fees paid to other countries and the monthly rent paid for our headquarters facility.
Aircraft Rent. Aircraft rent expense consists of all minimum lease payments under the terms of our aircraft and spare engine lease agreements recognized on a straight-line basis. Aircraft rent expense also includes supplemental rent. Supplemental rent is made up of maintenance reserves paid to aircraft lessors in advance of the performance of major maintenance activities that are not probable of being reimbursed and probable and estimable return condition obligations. Aircraft rent expense is net of the amortization of gains and losses on sale leaseback transactions on our flight equipment. As of December 31, 2018, 46 of our 128 aircraft and 12 of our 20 spare engines are financed under operating leases.
Depreciation and Amortization. Depreciation and amortization expense includes the depreciation of fixed assets we own and leasehold improvements. It also includes the amortization of capitalized software costs and heavy maintenance. Under the deferral method, the cost of our heavy maintenance is capitalized and amortized on a straight-line or usage basis until the earlier of the next estimated heavy maintenance event or the remaining lease term.
Distribution. Distribution expense includes all of our direct costs, including the cost of web support, our third-party call center, travel agent commissions and related GDS fees and credit card transaction fees, associated with the sale of our tickets and other products and services.
Maintenance, Materials and Repairs. Maintenance, materials and repairs expense includes parts, materials, repairs and fees for repairs performed by third-party vendors and in-house mechanics required to maintain our fleet. It excludes direct labor

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cost related to our own mechanics, which is included under salaries, wages and benefits. It also excludes the amortization of heavy maintenance expenses, which we defer under the deferral method of accounting and amortize as a component of depreciation and amortization expense.
Special Charges. Special charges include lease termination charges and ratification incentive payouts related to the new collective bargaining agreements with our pilots and dispatchers.
Loss on Disposal of Assets. Loss on disposal of assets includes the net losses on the disposal of our fixed assets.
Other Operating Expenses. Other operating expenses include airport operations expense and fees charged by third-party vendors for ground handling services and food and liquor supply service expenses, passenger re-accommodation expense, the cost of passenger liability and aircraft hull insurance, all other insurance policies except for employee related insurance, travel and training expenses for crews and ground personnel, professional fees, personal property taxes and all other administrative and operational overhead expenses. No individual item included in this category represented more than 5% of our total operating expenses.
Other (Income) Expense
Interest Expense. Interest expense in 2018, 2017 and 2016 was primarily related to the financing of purchased aircraft.
Capitalized Interest. The Company capitalizes the interest that is attributable to the outstanding PDP balances as a percentage of the related debt on which interest is incurred. Capitalized interest represents interest cost incurred during the acquisition period of a long-term asset and is the amount which theoretically could have been avoided had we not paid PDPs for the related aircraft or engines. Capitalization of interest ceases when the asset is ready for service. Capitalized interest for 2018, 2017 and 2016 primarily related to the interest incurred on long-term debt.
Interest Income. For 2018, interest income represents interest income earned on cash, cash equivalents, short-term investments and on funds required to be held in escrow in accordance with the terms of our Series 2017-1 EETC. For a detailed discussion of the Series 2017-1 EETC, refer to “Notes to the Financial Statements—13. Debt and Other Obligations.” For 2017, interest income primarily represents interest income earned on cash, cash equivalents and short-term investments. For 2016, interest income was primarily related to interest earned on cash, cash equivalents and on funds required to be held in escrow in accordance with the terms of our Series 2015-1 EETC.
Other Expense. Other expense primarily includes realized gains and losses related to foreign currency transactions.
Special Charges, Non-operating. For 2018, special charges, non-operating represents interest related to an aircraft purchase agreement for the acquisition of 14 A319 aircraft previously operated under operating leases. The contract was deemed a lease modification which resulted in a change of classification from operating leases to capital leases, until the purchase date of the aircraft. Please see "Notes to Financial Statements—5. Special Charges" for further discussion. We had no special charges, non-operating in 2017 and 2016.
Income Taxes
We account for income taxes using the asset and liability method. We record a valuation allowance to reduce the deferred tax assets reported if, based on the weight of the evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Deferred taxes are recorded based on differences between the financial statement basis and tax basis of assets and liabilities and available tax loss and credit carryforwards. In assessing the realizability of the deferred tax assets, we consider whether it is more likely than not that some or all of the deferred tax assets will be realized. In evaluating the ability to utilize our deferred tax assets, we consider all available evidence, both positive and negative, in determining future taxable income on a jurisdiction by jurisdiction basis.
Trends and Uncertainties Affecting Our Business
We believe our operating and business performance is driven by various factors affecting airlines and their markets, trends affecting the broader travel industry and trends affecting the specific markets and customer base that we target. The following key factors may affect our future performance.
Competition. The airline industry is highly competitive. The principal competitive factors in the airline industry are fare pricing, total price, flight schedules, aircraft type, passenger amenities, number of routes served from a city, customer service, safety record, reputation, code-sharing relationships, frequent flyer programs and redemption opportunities. Price competition occurs on a market-by-market basis through price discounts, changes in pricing structures, fare matching, target promotions and frequent flyer initiatives. Airlines typically use discount fares and other promotions to stimulate traffic during normally slower

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travel periods in efforts to maximize unit revenue. The prevalence of discount fares can be particularly acute when a competitor has excess capacity that it is under financial pressure to sell.
Beginning in 2015, and continuing into 2018, the airline industry saw greater and more persistent price discounting than in the preceding several years. In addition, significant airline capacity increases in certain major cities exerted strong downward price pressure in those markets. Finally, beginning in mid-2015 network carriers began matching low-cost carrier and ULCC pricing on portions of their marginal unsold capacity, particularly in their key hub markets. We expect the discounting trend to continue for the foreseeable future.
Moreover, the network carriers have developed a fare-class pricing approach, in which a portion of available seats may be sold at or near ULCC prices, but without most product features available to their passengers paying at higher fare levels on the same flight. Broad fare discounting may have the effect of diluting the profitability of revenues of high-cost carriers but the fare-class approach may allow network carriers to continue offering a competitive price to ULCCs on some flights or routes, while maintaining higher pricing to their traditional constituencies of corporate and less price-sensitive travelers. Refer to “Risk Factors—Risks Related to Our Industry—We operate in an extremely competitive industry."
Seasonality and Volatility. Our results of operations for any interim period are not necessarily indicative of those for the entire year because the air transportation business is subject to significant seasonal fluctuations. We generally expect demand to be greater in the second and third quarters compared to the rest of the year. The air transportation business is also volatile and highly affected by economic cycles and trends. Consumer confidence and discretionary spending, fear of terrorism or war, weakening economic conditions, fare initiatives, fluctuations in fuel prices, labor actions, changes in governmental regulations on taxes and fees, weather and other factors have resulted in significant fluctuations in revenues and results of operations in the past. We believe demand for business travel historically has been more sensitive to economic pressures than demand for low-price travel. Finally, a significant portion of our operations are concentrated in markets such as South Florida, the Caribbean, Latin America and the Northeast and northern Midwest regions of the United States, which are particularly vulnerable to weather, airport traffic constraints and other delays.
Aircraft Fuel. Fuel costs represents one of our largest operating expenses, as it does for most airlines. Fuel costs have been subject to wide price fluctuations in recent years. Fuel availability and pricing are also subject to refining capacity, periods of market surplus and shortage and demand for heating oil, gasoline and other petroleum products, as well as meteorological, economic and political factors and events occurring throughout the world, which we can neither control nor accurately predict. We source a significant portion of our fuel from refining resources located in the southeast United States, particularly facilities adjacent to the Gulf of Mexico. Gulf Coast fuel is subject to volatility and supply disruptions, particularly in hurricane season when refinery shutdowns have occurred, or when the threat of weather-related disruptions has caused Gulf Coast fuel prices to spike above other regional sources. Our fuel derivatives, if any, generally consist of jet fuel swaps and jet fuel options. Both jet fuel swaps and jet fuel options can be used at times to protect the refining price risk between the price of crude oil and the price of refined jet fuel, and to manage the risk of increasing fuel prices. Our fuel hedging practices are dependent upon many factors, including our assessment of market conditions for fuel, our access to the capital necessary to support margin requirements, the pricing of hedges and other derivative products in the market, our overall appetite for risk and applicable regulatory policies. As of December 31, 2018, we had no outstanding jet fuel derivatives and we have not engaged in fuel derivative activity since 2015. As of December 31, 2018, we purchased a majority of our aircraft fuel under a single fuel service contract. The cost and future availability of jet fuel cannot be predicted with any degree of certainty.
Labor. The airline industry is heavily unionized. The wages, benefits and work rules of unionized airline industry employees are determined by collective bargaining agreements, or CBAs. Relations between air carriers and labor unions in the United States are governed by the RLA. Under the RLA, CBAs generally contain “amendable dates” rather than expiration dates, and the RLA requires that a carrier maintain the existing terms and conditions of employment following the amendable date through a multi-stage and usually lengthy series of bargaining processes overseen by the NMB. This process continues until either the parties have reached agreement on a new CBA, or the parties have been released to “self-help” by the NMB. In most circumstances, the RLA prohibits strikes; however, after release by the NMB, carriers and unions are free to engage in self-help measures such as strikes and lockouts.
We have five union-represented employee groups comprising approximately 80% of our employees at December 31, 2018. Our pilots are represented by the Air Line Pilots Association, International, or ALPA, our flight attendants are represented by the Association of Flight Attendants, or AFA-CWA, our dispatchers are represented by the Professional Airline Flight Control Association, or PAFCA, our ramp service agents are represented by the International Association of Machinists and Aerospace Workers, or IAMAW, and our passenger service agents are represented by the Transport Workers Union, or TWU. Conflicts between airlines and their unions can lead to work slowdowns or stoppages.

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In August 2015, that collective bargaining agreement with our pilots, represented by ALPA, became amendable. In June 2016, ALPA requested the services of the National Mediation Board ("NMB") to facilitate negotiations for an amended agreement and we joined ALPA in the request. During 2017, we experienced operational disruption from pilot-related work action which adversely impacted our results. We obtained a temporary restraining order to enjoin further illegal labor action. In January 2018, under the guidance of the NMB assigned mediators, the parties reached a tentative amendable agreement and in February 2018, the pilot group voted to approve the new five-year agreement with the Company. In connection with this agreement, we incurred a one-time ratification incentive of $80.2 million, including payroll taxes, and an $8.5 million adjustment related to other contractual provisions. These amounts were recorded in special charges within operating expenses in the statement of operations for the year ended December 31, 2018. For further information, refer to “Notes to the Financial Statements—5. Special Charges.”
In March 2016, with the help of the NMB, we reached a tentative agreement for a five-year contract with our flight attendants. In May 2016, the flight attendants voted to approve the new five-year contract with the Company.
In December 2017, PAFCA filed an application with the NMB seeking to represent our dispatchers, who were previously represented by the TWU. In January 2018, the NMB determined that a representation election would be held. The voting period for the representation election took place through February 20, 2018 and the dispatchers elected to be represented by the PAFCA. In October 2018, we reached a tentative agreement for a new five-year agreement with our dispatchers, which was ratified by the PAFCA members in October 2018.
In July 2014, certain ramp service agents directly employed by the Company voted to be represented by the IAMAW. In May 2015, we entered into a five-year interim collective bargaining agreement with the IAMAW, covering material economic terms. In June 2016, with the help of the IAMAW, we reached an agreement on the remaining terms of the collective bargaining agreement, which is amendable in June 2020.
In June 2018, we were notified by the NMB that the TWU filed an application seeking a representation election for our passenger service agents. Our passenger service agents voted to be represented by the TWU, but the representation applies only to the Fort Lauderdale station where we have direct employees in the passenger service classification. We began meeting with the TWU in late October 2018 to negotiate an initial collective bargaining agreement. 
We believe the five-year term of our CBAs is valuable in providing stability to our labor costs and provide us with competitive labor costs compared to other U.S.-based low-cost carriers. If we are unable to reach agreement with any of our unionized work groups in current or future negotiations regarding the terms of their CBAs, we may be subject to work interruptions or stoppages, such as the strike by our pilots in June 2010. A strike or other significant labor dispute with our unionized employees is likely to adversely affect our ability to conduct business. Any agreement we do reach could increase our labor and related expenses.
In 2010, the Patient Protection and Affordable Care Act was passed into law. Under the current administration, this law may be repealed in its entirety or certain aspects may be changed or replaced. If the law is repealed or modified or if new legislation is passed, such action could potentially increase our operating costs, with healthcare costs increasing at a higher rate than our employee headcount.
Maintenance Expense. Maintenance expense grew through 2018, 2017 and 2016 mainly as a result of a growing fleet and the gradual increase of required maintenance for the older aircraft in our fleet. As the fleet ages, we expect that maintenance costs will increase in absolute terms. The amount of total maintenance costs and related amortization of heavy maintenance (included in depreciation and amortization expense) is subject to many variables such as future utilization rates, average stage length, the interval between heavy maintenance events, the size and makeup of the fleet in future periods and the level of unscheduled maintenance events and their actual costs. Accordingly, we cannot reliably quantify future maintenance expenses for any significant period of time. However, we believe, based on our scheduled maintenance events, maintenance expense and maintenance-related amortization expense in 2019 will be approximately $215 million. In addition, we expect to capitalize approximately $188 million of costs for heavy maintenance during 2019.

As a result of a majority of our fleet being acquired over a relatively short period of time, heavy maintenance scheduled on certain aircraft will overlap, meaning we will incur our most expensive scheduled maintenance obligations on certain aircraft at roughly the same time. These more significant maintenance activities will result in out-of-service periods during which our aircraft will be dedicated to maintenance activities and unavailable to fly revenue service. When accounting for maintenance expense under the deferral method, heavy maintenance is amortized over the shorter of either the remaining lease term or the next estimated heavy maintenance event. As a result, deferred maintenance events occurring closer to the end of the lease term will generally have shorter amortization periods than those occurring earlier in the lease term. This will create higher depreciation and amortization expense specific to any aircraft related to heavy maintenance during the final years of the

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lease as compared to earlier periods. Please see “Critical Accounting Policies and Estimates-Aircraft Maintenance, Materials, Repair Costs and Related Heavy Maintenance Amortization.”
Maintenance Reserve Obligations. The terms of some of our aircraft lease agreements require us to post deposits for future maintenance, also known as maintenance reserves, to the lessor in advance of and as collateral for the performance of major maintenance events, resulting in our recording significant prepaid deposits on our balance sheet. As a result, the cash costs of scheduled major maintenance events are paid in advance of the recognition of the maintenance event in our results of operations. Please see “—Critical Accounting Policies and Estimates—Aircraft Maintenance, Materials, Repair Costs and Related Heavy Maintenance Amortization” and “—Maintenance Reserves.”
Critical Accounting Policies and Estimates
The following discussion and analysis of our financial condition and results of operations is based on our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amount of assets and liabilities, revenues and expenses and related disclosure of contingent assets and liabilities at the date of our financial statements. For a detailed discussion of our significant accounting policies, refer to “Notes to Financial Statements—1. Summary of Significant Accounting Policies.”
Critical accounting policies are defined as those policies that reflect significant judgments or estimates about matters both inherently uncertain and material to our financial condition or results of operations.
Revenue Recognition. Revenues from tickets sold are initially deferred as ATL. Passenger revenues are recognized when transportation is provided. An unused non-refundable ticket expires at the date of scheduled travel and is recognized as revenue for the expired ticket value at the date of scheduled travel. As of December 31, 2018 and 2017, we had air traffic liability ("ATL") balances of $292.0 million and $263.7 million, respectively. As of December 31, 2018, all of the ATL balance as of December 31, 2017 has been recognized.
Customers may elect to change or cancel their itinerary prior to the date of departure. For changes, a service charge is recognized at time of departure of newly scheduled travel and is deducted from the face value of the original purchase price of the ticket, and the original ticket becomes invalid. For cancellations, a service charge is assessed and the amount remaining after deducting the service charge is called a credit shell which generally expires 60 days from the date the credit shell is created and can be used towards the purchase of a new ticket and the Company’s other service offerings. Both the service charge and credit shell amounts are recorded as deferred revenue and amounts expected to expire unused are estimated based on historical experience. Estimating the amount of credits that will go unused involves some level of subjectivity and judgment. However, given the relatively short period of time to expiration, this does not have a significant impact on the Company's financial statements.
Frequent Flyer Program. Our frequent flyer program generates customer loyalty by rewarding customers with mileage credits to travel on Spirit. When traveling, customers earn redeemable mileage credits for each mile flown on Spirit. Customers can also earn mileage credits through participating companies such as the co-branded Spirit credit card. Mileage credits are redeemable by customers in future periods for air travel on Spirit.

To reflect the mileage credits earned, the program includes two types of transactions that are considered revenue arrangements with multiple performance obligations: (1) mileage credits earned with travel and (2) mileage credits sold to co-branded credit card partner.

The adoption of ASU 2014-09 eliminated the incremental cost method for frequent flyer program accounting, which required us to re-value and record a liability associated with customer flight miles earned with travel as part of our frequent flyer program with a relative fair value. Upon adoption of ASU 2014-09 on January 1, 2018, we recorded an increase to our air traffic liability of $12.4 million.

Passenger ticket sales earning mileage credits. Passenger ticket sales earning mileage credits provide customers with (1) mileage credits earned and (2) air transportation. We value each performance obligation on a standalone basis. To value the mileage credits earned, we consider the quantitative value a passenger receives by redeeming miles for a ticket rather than paying cash, which is referred to as equivalent ticket value ("ETV").

We defer revenue for the mileage credits when earned and recognize loyalty travel awards in passenger revenue as the miles are redeemed and services are provided. We record the air transportation portion of the passenger ticket sales in air traffic

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liability and recognize passenger revenue when transportation is provided or if the ticket goes unused, at the date of scheduled travel.

Sale of mileage credits. Customers may earn mileage credits based on their spending with our co-branded credit card company with which we have an agreement to sell mileage credits. The contract to sell mileage credits under this agreement has multiple performance obligations. During the year ended December 31, 2018 and 2017, total cash sales from this agreement were $39.2 million and $49.5 million, respectively, which are allocated to travel and other performance obligations.

Our co-brand credit card agreement provides for joint marketing where cardholders earn mileage credits for making purchases using co-branded cards. During 2015, we extended its agreement with the administrator of the FREE SPIRIT affinity credit card program to extend through 2022. We account for this agreement consistently with the accounting method that allocates the consideration received to the individual products and services delivered. The value is allocated based on the relative selling prices of those products and services, which generally consists of (i) travel miles to be awarded, (ii) licensing of brand and access to member lists and (iii) advertising and marketing efforts. We determined the best estimate of the selling prices by considering discounted cash flow analysis using multiple inputs and assumptions, including: (1) the expected number of miles awarded and number of miles redeemed, (2) ETV for the award travel obligation, (3) licensing of brand and access to member lists and (4) advertising and marketing efforts. 

We defer the amount for award travel obligation as part of loyalty deferred revenue within air traffic liability on the balance sheet and recognize loyalty travel awards in passenger revenue as the mileage credits are used for travel. Revenue allocated to the remaining performance obligations, primarily marketing components, is recorded in other revenue over time as miles are delivered. Total unrecognized revenue from future FREE SPIRIT award redemptions and the sale of mileage credits was $27.4 million and $26.6 million at December 31, 2018 and 2017, respectively. The current portion of this balance is recorded within air traffic liability and the long-term portion of this balance is recorded within deferred gains and other long-term liabilities in the accompanying balance sheets.

Mileage breakage. For mileage credits that we estimate are not likely to be redeemed ("breakage"), we recognize the associated value proportionally during the period in which the remaining mileage credits are redeemed. Management uses statistical models to estimate breakage based on historical redemption patterns. A change in assumptions as to the period over which mileage credits are expected to be redeemed, the actual redemption activity for mileage credits or the estimated fair value of mileage credits expected to be redeemed could have an impact on revenues in the year in which the change occurs and in future years.

Current activity of frequent flyer program. Mileage credits are combined in one homogeneous pool and are not separately identifiable. As such, revenue is comprised of miles that were part of the frequent flyer deferred revenue balance at the beginning of the period as well as miles that were issued during the period.

Refer to “Notes to the Financial Statements—3, Revenue Recognition and 4, Revenue Disaggregation" for information regarding our adoption of ASU 2014-09.
Accounting for property and equipment. Property and equipment is stated at cost, less accumulated depreciation and amortization. Depreciation of operating property and equipment is computed using the straight-line method applied to each unit of property. Property under capital leases and related obligations are initially recorded at an amount equal to the present value of future minimum lease payments computed using our incremental borrowing rate or, when known, the interest rate implicit in the lease. Amortization of property under capital leases is on a straight-line basis over the lease term and is included in depreciation and amortization expense. In accounting for property and equipment, we must make estimates about the expected useful lives of the assets, the expected residual values of the assets, and the potential for impairment based on the fair value of the assets and their future expected cash flows.
The depreciable lives used for the principal depreciable asset classifications are:

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Estimated Useful Life
Aircraft, engines and flight simulators
25 years
Spare rotables and flight assemblies
7 to 15 years
Other equipment and vehicles
5 to 7 years
Internal use software
3 to 10 years
Capital leases
Lease term
Leasehold improvements
Lesser of lease term or estimated useful life of the improvement
Buildings
Lesser of lease term or 30 years
As of December 31, 2018, we had 82 aircraft, 8 spare engines and 1 flight simulator capitalized within flight equipment with depreciable lives of 25 years. As of December 31, 2018, we had 46 aircraft financed through operating leases with lease terms of 8 to 18 years and 12 spare engines financed through operating leases with lease terms of 2 to 14 years. Residual values for new aircraft, new engines, major spare rotable parts, avionics and assemblies are generally estimated to be 10%.
We record impairment charges on long-lived assets used in operations when events and circumstances indicate the assets may be impaired, the undiscounted cash flows estimated to be generated by those assets are less than the carrying amount of those assets, and the net book value of the assets exceeds their estimated fair value. In making these determinations, we use certain assumptions, including, but not limited to: (i) estimated fair value of the assets; and (ii) estimated, undiscounted future cash flows expected to be generated by these assets, which are based on additional assumptions such as asset utilization, length of service the asset will be used in our operations, and estimated salvage values.
Aircraft Maintenance, Materials, Repair Costs and Related Heavy Maintenance Amortization. We account for heavy maintenance under the deferral method. Under the deferral method the cost of heavy maintenance is capitalized and amortized as a component of depreciation and amortization expense over the earlier of the next estimated heavy maintenance event or the remaining lease term or useful life of the aircraft. Management expects that heavy maintenance events occurring closer to the end of the lease term will be amortized over the remaining lease term rather than over the next estimated heavy maintenance event. Amortization of engine and aircraft overhaul costs was $41.3 million, $53.9 million and $43.8 million for the years ended December 31, 2018, 2017 and 2016, respectively. If heavy maintenance costs were amortized within maintenance, material and repairs expense in the statements of operations, our maintenance, material and repairs expense would have been $170.4 million, $164.3 million and $142.4 million for the years ended December 31, 2018, 2017 and 2016, respectively. During the years ended December 31, 2018, 2017 and 2016, we capitalized $190.5 million, $78.2 million and $35.4 million of costs for heavy maintenance, respectively. The timing of the next heavy maintenance event is estimated based on assumptions including estimated usage, FAA-mandated maintenance intervals, current condition of the related component, the age of the related component and average removal times as suggested by the manufacturer. These assumptions may change based on changes in our utilization of our aircraft, changes in government regulations and suggested manufacturer maintenance intervals. In addition, these assumptions can be affected by unplanned incidents that could damage an airframe, engine or major component to a level that would require a heavy maintenance event prior to a scheduled maintenance event. To the extent the estimated timing of the next maintenance event is extended or shortened, the related amortization period would be lengthened or shortened, resulting in higher amortization expense over a shorter period or lower amortization expense over a longer period, respectively. Heavy maintenance events include 6-year and 12-year airframe checks, engine overhauls, LLP replacement and overhauls to major components. Certain maintenance functions are outsourced under contracts that