Item 1. BUSINESS

General

We provide scheduled air transportation for passengers and cargo throughout the United States ("U.S.") and around the world. Our global route network gives us a presence in every major domestic and international market. Our route network is centered around a system of hub, international gateway and key airports that we operate in Amsterdam, Atlanta, Boston, Detroit, London-Heathrow, Los Angeles, Minneapolis-St. Paul, New York-LaGuardia, New York-JFK, Paris-Charles de Gaulle, Salt Lake City, Seattle and Tokyo-Narita. Each of these operations includes flights that gather and distribute traffic from markets in the geographic region surrounding the hub or gateway to domestic and international cities and to other hubs or gateways. Our network is supported by a fleet of aircraft that is varied in size and capabilities, giving us flexibility to adjust aircraft to the network. Other important characteristics of our route network include our international joint ventures, our alliances with other foreign airlines, our membership in SkyTeam and agreements with multiple domestic regional carriers that operate as Delta Connection®.

We are incorporated under the laws of the State of Delaware. Our principal executive offices are located at Hartsfield-Jackson Atlanta International Airport in Atlanta, Georgia. Our telephone number is (404) 715-2600 and our Internet address is www.delta.com. Information contained on our website is not part of, and is not incorporated by reference in, this Form 10-K.

International Alliances

Our international alliance relationships with foreign carriers are an important part of our business as they improve our access to international markets and enable us to market globally integrated air transportation services. The most significant of these arrangements are commercial joint ventures that include joint sales and marketing coordination, co-location of airport facilities and other commercial cooperation arrangements. Our alliance arrangements also include reciprocal codesharing and reciprocal frequent flyer program participation and airport lounge access arrangements. These alliance relationships also may present opportunities in other areas, such as airport ground handling arrangements, aircraft maintenance insourcing and joint procurement.

Joint Venture Agreements. We currently operate four joint ventures with foreign carriers and have entered into an agreement to form a fifth. These arrangements, for which we have received antitrust immunity from the U.S. Department of Transportation ("DOT"), provide for joint commercial cooperation with our partners within the geographic scope of those arrangements, including the sharing of revenues and/or profits and losses generated by the parties on the joint venture routes, as well as joint marketing and sales, coordinated pricing and revenue management, network planning and scheduling and other coordinated activities with respect to the parties' operations on joint venture routes. Our commercial joint ventures are:

•	A transatlantic joint venture with Air France and KLM, both of which are subsidiaries of the same holding company, and Alitalia.

•	A joint venture with Virgin Atlantic Airways with respect to operations on non-stop routes between the United Kingdom and North America. In addition to the joint venture, we own a non-controlling 49% equity stake in Virgin Atlantic Limited, the parent company of Virgin Atlantic Airways.

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A joint venture with Aeroméxico with respect to trans-border operations on flights between the U.S. and Mexico. In addition to the joint venture, we acquired a non-controlling 49% equity stake in Grupo Aeroméxico, S.A.B. de C.V., the parent company of Aeroméxico. In addition, we and Aeroméxico have established a joint venture relating to an airframe maintenance, repair and overhaul operation located in Queretaro, Mexico.

•	A joint venture with Virgin Australia Airlines and its affiliated carriers with respect to operations on transpacific routes between North America and Australia/New Zealand.

•	In 2017, we entered into a joint venture with Korean Air Lines with respect to operations on transpacific routes between the United States and certain countries in Asia. We have not yet implemented this joint venture as it remains subject to receipt of required regulatory approvals in Korea.

Enhanced Commercial Agreements with Foreign Carriers. We have a strategic equity investment in GOL Linhas Aéreas Inteligentes, S.A., the parent company of Gol Linhas Aéreas (a Brazilian air carrier), and an exclusive commercial cooperation relationship with GOL, which includes reciprocal codesharing and frequent flyer program participation, airport lounge access arrangements and joint sales cooperation.

We also own shares of China Eastern and entered into a joint marketing agreement with China Eastern in 2015 to expand our commercial cooperation and better connect the networks of the two airlines.

SkyTeam. In addition to our marketing alliance agreements with individual foreign airlines, we are a member of the SkyTeam global airline alliance. The other members of SkyTeam are Aeroflot, Aerolíneas Argentinas, Aeroméxico, Air Europa, Air France, Alitalia, China Airlines, China Eastern, China Southern, CSA Czech Airlines, Garuda Indonesia, Kenya Airways, KLM, Korean Air, Middle East Airlines, Saudi Arabian Airlines, Tarom, Vietnam Airlines and Xiamen Airlines. Through alliance arrangements with other SkyTeam carriers, Delta is able to link its network with the route networks of the other member airlines, providing opportunities for increased connecting traffic while offering enhanced customer service through reciprocal codesharing and frequent flyer arrangements, airport lounge access programs and coordinated cargo operations.

Regional Carriers

We have air service agreements with domestic regional air carriers that feed traffic to our route system by serving passengers primarily in small and medium-sized cities. These arrangements enable us to better match capacity with demand in these markets. Approximately 16% of our passenger revenue in 2017 was related to flying by these regional air carriers.

Through our regional carrier program, Delta Connection, we have contractual arrangements with regional carriers to operate aircraft using our "DL" designator code. We have contractual arrangements with:

•	ExpressJet Airlines, Inc. and SkyWest Airlines, Inc., both subsidiaries of SkyWest, Inc.;

•	Republic Airline, Inc. ("Republic"), a subsidiary of Republic Airways Holdings, Inc.;

•	Compass Airlines, LLC ("Compass") and GoJet Airlines, LLC, both subsidiaries of Trans States Holdings, Inc. ("Trans States"); and

•	Endeavor Air, Inc., which is a wholly owned subsidiary of ours.

Our contractual agreements with regional carriers primarily are capacity purchase arrangements, under which we control the scheduling, pricing, reservations, ticketing and seat inventories for the regional carriers' flights operating under our "DL" designator code. We are entitled to all ticket, cargo, mail, in-flight and ancillary revenues associated with these flights. We pay those airlines an amount, as defined in the applicable agreement, which is based on a determination of their cost of operating those flights and other factors intended to approximate market rates for those services. These capacity purchase agreements are long-term agreements, usually with initial terms of at least 10 years, which grant us the option to extend the initial term. Certain of these agreements provide us the right to terminate the entire agreement, or in some cases remove some of the aircraft from the scope of the agreement, for convenience at certain future dates.

SkyWest Airlines operates some flights for us under a revenue proration agreement. This proration agreement establishes a fixed dollar or percentage division of revenues for tickets sold to passengers traveling on connecting flight itineraries.

Frequent Flyer Program

Our SkyMiles® frequent flyer program ("SkyMiles program") is designed to retain and increase traveler loyalty by offering incentives to customers to increase travel on Delta. The SkyMiles program allows program members to earn mileage credit for travel awards by flying on Delta, its regional carriers and other participating airlines. Mileage credit may also be earned by using certain services offered by program participants, such as credit card companies, hotels and car rental agencies. In addition, individuals may purchase mileage credits. Miles do not expire, but are subject to the program rules. We reserve the right to terminate the program with six months advance notice, and to change the program's terms and conditions at any time without notice.

SkyMiles program mileage credits can be redeemed for air travel on Delta and participating airlines, for membership in our Delta Sky Clubs® and for other program participant awards. Mileage credits are subject to certain transfer restrictions and travel awards on partner airlines are subject to capacity-controlled seating. We offer last-seat availability for travel awards on our own flights (including most Delta Connection flights). In 2017, program members redeemed more than 345 billion miles in the SkyMiles program for 14.9 million award redemptions. During this period, 7.9% of revenue miles flown on Delta were from award travel.

Fuel

Our results of operations are significantly impacted by changes in the price and availability of aircraft fuel. The following table shows our aircraft fuel consumption and costs.

Year	Gallons Consumed**(1)** (in millions)		Cost**(1)(2)** (in millions)			Average Price Per Gallon**(1)(2)**			Percentage of Total Operating Expense**(1)(2)**
2017	4,032		$	6,756		$	1.68		19.2	%
2016	4,016		$	5,985		$	1.49		18.3	%
2015	3,988		$	7,579		$	1.90		23.0	%

(1)	Includes the operations of our regional carriers operating under capacity purchase agreements.

(2)	Includes the impact of fuel hedge activity and refinery segment results.

General

We purchase most of our aircraft fuel under contracts that establish the price based on various market indices and therefore do not provide material protection against price increases or assure the availability of our fuel supplies. We also purchase aircraft fuel on the spot market, from off-shore sources and under contracts that permit the refiners to set the price.

Monroe Energy

Our wholly owned subsidiaries, Monroe Energy, LLC and MIPC, LLC (collectively, "Monroe") operate the Trainer refinery and related assets located near Philadelphia, Pennsylvania. The facilities include pipelines and terminal assets that allow the refinery to supply jet fuel to our airline operations throughout the Northeastern U.S., including our New York hubs at LaGuardia and JFK. These companies are distinct from us, operating under their own management teams and with their own boards of managers. We own Monroe as part of our strategy to mitigate the cost of the refining margin reflected in the price of jet fuel, as well as to maintain sufficiency of supply to our New York operations.

Refinery Operations. The facility is capable of refining approximately 200,000 barrels of crude oil per day. In addition to jet fuel, the refinery's production consists of gasoline, diesel and other refined products ("non-jet fuel products"). Monroe sources domestic and foreign crude oil supply from a variety of providers.

Strategic Agreements. Monroe exchanges the non-jet fuel products the refinery produces with third parties for jet fuel consumed in our airline operations.

Segments. Because the products and services of Monroe's refinery operations are discrete from our airline services, segment results are prepared for our airline segment and our refinery segment. Financial information on our segment reporting can be found in Note 14 of the Notes to the Consolidated Financial Statements.

Fuel Hedging Program

We have recently managed our fuel price risk through a hedging program intended to reduce the financial impact from changes in the price of fuel as fuel prices are subject to potential volatility. We may utilize different contract and commodity types in this program and frequently test their economic effectiveness against our financial targets. We closely monitor the hedge portfolio and rebalance the portfolio based on market conditions, which may result in locking in gains or losses on hedge contracts prior to their settlement dates. In addition, we enter into derivatives with third parties to hedge financial risk related to Monroe’s refining margins.

Fuel Supply Availability

We are currently able to obtain adequate supplies of aircraft fuel, including fuel produced by Monroe or procured through the exchange of non-jet fuel products the refinery produces, and crude oil for Monroe's operations. However, it is impossible to predict the future availability or price of aircraft fuel and crude oil. Weather-related events, natural disasters, political disruptions or wars involving oil-producing countries, changes in government policy concerning aircraft fuel production, transportation, taxes or marketing, changes in refining capacity, environmental concerns and other unpredictable events may result in future fuel supply shortages and fuel price increases.

Other Businesses

Cargo

Through our global network, our cargo operations are able to connect the world's major freight gateways. We generate cargo revenues in domestic and international markets through the use of cargo space on regularly scheduled passenger aircraft. We are a member of SkyTeam Cargo, a global airline cargo alliance, whose other members are Aeroflot, Aerolíneas Argentinas, Aeroméxico Cargo, Air France-KLM Cargo, Alitalia Cargo, China Airlines Cargo, China Cargo Airlines, China Southern Cargo, Czech Airlines Cargo and Korean Air Cargo. SkyTeam Cargo offers a global network spanning six continents.

Ancillary Businesses

We have several other businesses arising from our airline operations, including aircraft maintenance, repair and overhaul ("MRO"), staffing and other services, vacation wholesale operations and our private jet operations. In 2017, the total revenue from these businesses was approximately $1 billion.

•	In addition to providing maintenance and engineering support for our fleet of over 900 aircraft, our MRO operation, known as Delta TechOps, serves aviation and airline customers from around the world.

•	Delta Global Services provides services to us and to third parties, including staffing services, aviation solutions, professional security and training services.

•	Our vacation wholesale business, Delta Vacations, provides vacation packages to third-party consumers.

•	Our private jet operations, Delta Private Jets, provides aircraft charters, aircraft management and programs allowing members to purchase flight time by the hour.

Distribution and Expanded Product Offerings

Our tickets are sold through various distribution channels, including: (1) digital channels, such as delta.com and mobile applications/web, (2) telephone reservations, (3) online travel agencies and (4) traditional "brick and mortar" and other agencies. We make fare and product information widely available across those channels, ensuring customers always receive the best information and service options. An increasing number of our tickets are sold through Delta digital direct channels, driving more direct, personalized interactions with our customers and reducing distribution costs.

We have transformed distribution to a more retail oriented, merchandised approach by introducing well-defined and differentiated products for our customers. We offer distinct travel experiences with clear value propositions that enable customer choice. Delta OneTM, Delta Premium Select, First Class and Delta Comfort+TM include varying premium amenities and services while Main Cabin and Basic Economy allow varying levels of pre-travel flexibility as well as exceptional service once onboard the aircraft. We expect that these merchandising initiatives as implemented across all of Delta's distribution channels will allow customers to better understand our product offerings, make it easier to buy the products they desire and increase customer satisfaction. This merchandising effort is most effective in Delta's digital channels where customers can compare all product options in a single, easy to understand display.

Technology Transformation

Significant progress was made in 2017 in the transformation of our information technology function to improve operational reliability and enhance disaster recovery capabilities. Most significantly, we opened a new data center to provide redundancy for our key systems and continue the enhancement of that facility. We also reduced the risk of technology system failures to our operations through additional disaster recovery processes and heightened emphasis on our information security program including through the hiring of an experienced information security professional as our Chief Information Security Officer.

We are engaged in a digital transformation by continuing to invest in technology that supports our operations and provides tools for our employees, with our long term goal to convert our technology into a competitive advantage. These investments include improvements to infrastructure and technology architecture to unify and improve access to data sources and continue innovations in customer facing applications. This digital transformation will enhance interactions with our customers and allow us to deliver more personalized service, further enhancing the customer experience and strengthening our brand and competitive position.

Competition

The airline industry is highly competitive, marked by significant competition with respect to routes, fares, schedules (both timing and frequency), services, products, customer service and frequent flyer programs. The industry has evolved through mergers and new entry, both domestically and internationally, and changes in international alliances. Consolidation in the airline industry, the rise of well-funded government sponsored international carriers, changes in international alliances and the creation of immunized joint ventures have altered, and will continue to alter, the competitive landscape in the industry, resulting in the formation of airlines and alliances with increased financial resources, more extensive global networks and more competitive cost structures.

Domestic

Our domestic operations are subject to competition from traditional network carriers, including American Airlines and United Airlines, national point-to-point carriers, including Alaska Airlines, JetBlue Airways and Southwest Airlines, and discount carriers, some of which may have lower costs than we do and provide service at low fares to destinations served by us. Point-to-point, discount and ultra low-cost carriers, including Spirit Airlines and Allegiant Air, place significant competitive pressure on network carriers in the domestic market. In particular, we face significant competition at our domestic hub and gateway airports either directly at those airports or at the hubs of other airlines that are located in close proximity to our hubs and gateways. We also face competition in smaller to medium-sized markets from regional jet operations of other carriers.

International

Our international operations are subject to competition from both foreign and domestic carriers. Competition is increasing from government-owned and -funded carriers in the Gulf region, including Emirates, Etihad Airways and Qatar Airways. These carriers have large numbers of international widebody aircraft on order and are increasing service to the U.S. These carriers are government-subsidized, which has allowed them to grow quickly, reinvest in their product and expand their global presence at the expense of U.S. airlines.

Through alliance and other marketing and codesharing agreements with foreign carriers, U.S. carriers have increased their ability to sell international transportation, such as services to and beyond traditional European and Asian gateway cities. Similarly, foreign carriers have obtained increased access to interior U.S. passenger traffic beyond traditional U.S. gateway cities through these relationships. In particular, alliances formed by domestic and foreign carriers, including SkyTeam, the Star Alliance (among United Airlines, Lufthansa German Airlines, Air Canada and others) and the oneworld alliance (among American Airlines, British Airways, Qantas and others) have enhanced competition in international markets.

In addition, several joint ventures among U.S. and foreign carriers, including our transatlantic and transpacific joint ventures, have received grants of antitrust immunity allowing the participating carriers to coordinate schedules, pricing, sales and inventory. Other joint ventures that have received antitrust immunity include a transatlantic alliance among United Airlines, Air Canada and Lufthansa German Airlines, a transpacific joint venture between United Airlines and All Nippon Airways, a transatlantic joint venture among American Airlines, British Airways and Iberia and a transpacific joint venture between American Airlines and Japan Air Lines.

Regulatory Matters

The DOT and the Federal Aviation Administration (the "FAA") exercise regulatory authority over air transportation in the U.S. The DOT has authority to issue certificates of public convenience and necessity required for airlines to provide domestic air transportation. An air carrier that the DOT finds fit to operate is given authority to operate domestic and international air transportation (including the carriage of passengers and cargo). Except for constraints imposed by regulations regarding "Essential Air Services," which are applicable to certain small communities, airlines may terminate service to a city without restriction.

The DOT has jurisdiction over certain economic and consumer protection matters, such as unfair or deceptive practices and methods of competition, advertising, denied boarding compensation, baggage liability and disabled passenger transportation. The DOT also has authority to review certain joint venture agreements between domestic and international carriers and engages in regulation of economic matters such as slot transactions. The FAA has primary responsibility for matters relating to the safety of air carrier flight operations, including airline operating certificates, control of navigable air space, flight personnel, aircraft certification and maintenance and other matters affecting air safety.

Authority to operate international routes and international codesharing arrangements is regulated by the DOT and by the governments of the foreign countries involved. International certificate authorities are also subject to the approval of the U.S. President for conformance with national defense and foreign policy objectives.

The Transportation Security Administration and the U.S. Customs and Border Protection, each a division of the Department of Homeland Security, are responsible for certain civil aviation security matters, including passenger and baggage screening at U.S. airports and international passenger prescreening prior to entry into or departure from the U.S.

Airlines are also subject to various other federal, state, local and foreign laws and regulations. For example, the U.S. Department of Justice has jurisdiction over airline competition matters. The U.S. Postal Service has authority over certain aspects of the transportation of mail. Labor relations in the airline industry, as discussed below, are generally governed by the Railway Labor Act. Environmental matters are regulated by various federal, state, local and foreign governmental entities. Privacy of passenger and employee data is regulated by domestic and foreign laws and regulations.

Fares and Rates

Airlines set ticket prices in all domestic and most international city pairs with minimal governmental regulation, and the industry is characterized by significant price competition. Certain international fares and rates are subject to the jurisdiction of the DOT and the governments of the foreign countries involved. Many of our tickets are sold by travel agents, and fares are subject to commissions, overrides and discounts paid to travel agents, brokers and wholesalers.

Route Authority

Our flight operations are authorized by certificates of public convenience and necessity and also by exemptions and limited-entry frequency awards issued by the DOT. The requisite approvals of other governments for international operations are controlled by bilateral agreements (and a multilateral agreement in the case of the U.S. and the European Union) with, or permits or approvals issued by, foreign countries. Because international air transportation is governed by bilateral or other agreements between the U.S. and the foreign country or countries involved, changes in U.S. or foreign government aviation policies could result in the alteration or termination of such agreements, diminish the value of our international route authorities or otherwise affect our international operations. Bilateral agreements between the U.S. and various foreign countries served by us are subject to renegotiation from time to time. The U.S. government has negotiated "Open Skies" agreements with many countries, which allow unrestricted access between the U.S. and the foreign markets. These agreements include separate agreements with the European Union and Japan.

Certain of our international route authorities are subject to periodic renewal requirements. We request extension of these authorities when and as appropriate. While the DOT usually renews temporary authorities on routes where the authorized carrier is providing a reasonable level of service, there is no assurance this practice will continue in general or with respect to a specific renewal. Dormant route authorities may not be renewed in some cases, especially where another U.S. carrier indicates a willingness to provide service.

Airport Access

Operations at three major domestic airports and certain foreign airports served by us are regulated by governmental entities through allocations of "slots" or similar regulatory mechanisms which limit the rights of carriers to conduct operations at those airports. Each slot represents the authorization to land at or take off from the particular airport during a specified time period.

In the U.S., the FAA currently regulates the allocation of slots, slot exemptions, operating authorizations, or similar capacity allocation mechanisms at Reagan National in Washington, D.C. and LaGuardia and JFK in the New York City area. Our operations at these airports generally require the allocation of slots or analogous regulatory authorizations. Similarly, our operations at Tokyo's Narita and Haneda airports, London's Heathrow airport and other international airports are regulated by local slot coordinators pursuant to the International Air Transport Association's Worldwide Scheduling Guidelines and applicable local law. We currently have sufficient slots or analogous authorizations to operate our existing flights, and we have generally been able to obtain the rights to expand our operations and to change our schedules. There is no assurance, however, that we will be able to do so in the future because, among other reasons, such allocations are subject to changes in governmental policies.

Environmental Matters

Our operations are subject to a number of international, federal, state and local laws and regulations governing protection of the environment, including regulation of greenhouse gases and other air emissions, noise reduction, water discharges, aircraft drinking water, storage and use of petroleum and other regulated substances, and the management and disposal of hazardous waste, substances and materials.

Emissions. Greenhouse gas emissions by the aviation industry and their impact on climate change have become a particular focus in the international community and within the U.S. For several years, the European Union has required its member states to implement regulations to include aviation in its Emissions Trading Scheme ("ETS"). Under these regulations, any airline with flights originating or landing in the European Union is subject to the ETS and, beginning in 2012, was required to purchase emissions allowances if the airline exceeds the number of free allowances allocated to it under the ETS. The ETS was amended to apply only to flights within the European Economic Area from 2013 through 2016. In 2017, the EU extended the exemption for foreign flights through 2023 given the International Civil Aviation Organization’s ("ICAO") adoption of a global market-based program.

In October 2016, ICAO formally adopted a global, market-based emissions offset program known as the Carbon Offsetting and Reduction Scheme for International Aviation. This program is designed to achieve a medium-term goal for the aviation industry of achieving carbon-neutral growth in international aviation beginning in 2020. A pilot phase of the offset program will begin in 2021, followed by a first phase of the program beginning in 2024 and a second phase beginning in 2027. Countries can voluntarily participate in the pilot and first phase, but participation in the second phase is mandatory. In 2016, ICAO also adopted new aircraft certification standards to reduce carbon dioxide (CO2) emissions from aircraft. The new aircraft certification standards will apply to new aircraft types in 2020 and to new in-production aircraft starting in 2023 but no later than 2028. It is important to note that the standards will not apply to existing in-service aircraft. However, exemption from the certification requirement would provide no protection from taxation schemes based on CO2 emissions.

In July 2016, the U.S. Environmental Protection Agency ("EPA") issued a final finding under the Clean Air Act that greenhouse gases threaten the public health and welfare, and further determined that aircraft cause or contribute to greenhouse gases. The endangerment finding does not establish standards, but triggers an obligation for the EPA to regulate greenhouse gas emissions from aircraft. The EPA has historically implemented air emissions control standards adopted by ICAO; therefore, the ICAO aircraft engine certification standards are expected to influence the development of any EPA greenhouse gas emission standards for aircraft.

We may face additional regulation of aircraft emissions in the U.S. and abroad and become subject to further taxes, charges or additional requirements to obtain permits or purchase allowances or emission credits for greenhouse gas emissions in various jurisdictions. Additional regulation could result in taxation or permitting requirements from multiple jurisdictions for the same operations and significant costs for us and the airline industry. In addition to direct costs, such regulation could result in increased fuel costs passed through from fuel suppliers affected by any such regulations. We are monitoring and evaluating the potential impact of such legislative and regulatory developments.

We seek to minimize the impact of greenhouse gas emissions from our operations through reductions in our fuel consumption and other efforts, and have realized reductions in our greenhouse gas emission levels since 2005. We have reduced the fuel needs of our aircraft fleet through the retirement of older, less fuel efficient aircraft and replacement with newer, more fuel efficient aircraft. In addition, we have implemented fuel saving procedures in our flight and ground support operations that further reduce carbon emissions. We are also supporting efforts to develop alternative fuels and efforts to modernize the air traffic control system in the U.S. as part of our efforts to reduce our emissions and minimize our impact on the environment.

Noise. The Airport Noise and Capacity Act of 1990 recognizes the rights of operators of airports with noise problems to implement local noise abatement programs so long as such programs do not interfere unreasonably with interstate or foreign commerce or the national air transportation system. This statute generally provides that local noise restrictions on Stage 3 aircraft first effective after October 1, 1990, require FAA approval. While we have had sufficient scheduling flexibility to accommodate local noise restrictions in the past, our operations could be adversely impacted if locally-imposed regulations become more restrictive or widespread. In addition, foreign governments may allow airports to enact similar restrictions, which could adversely impact our international operations or require significant expenditure in order for our aircraft to comply with the restrictions.

Refinery Matters. Monroe's operation of the Trainer refinery is subject to numerous environmental laws and extensive regulations, including those relating to the discharge of materials into the environment, waste management, pollution prevention measures and greenhouse gas emissions.

Under the Energy Independence and Security Act of 2007, the EPA has adopted Renewable Fuel Standards ("RFS") that mandate the blending of renewable fuels into gasoline and on-road diesel ("Transportation Fuels"). Renewable Identification Numbers ("RINs") are assigned to renewable fuels produced or imported into the U.S. that are blended into Transportation Fuels to demonstrate compliance with this obligation. A refinery may meet its obligation under RFS by blending the necessary volumes of renewable fuels with Transportation Fuels or by purchasing RINs in the open market or through a combination of blending and purchasing RINs. Because the refinery operated by Monroe does not blend renewable fuels, it must purchase its RINs requirement in the secondary market or obtain a waiver from the EPA.

Other Environmental Matters. We are subject to certain environmental laws and contractual obligations governing the management and release of regulated substances, which may require the investigation and remediation of affected sites. Soil and/or ground water impacts have been identified at certain of our current or former leaseholds at several domestic airports. To address these impacts, we have a program in place to investigate and, if appropriate, remediate these sites. Although the ultimate outcome of these matters cannot be predicted with certainty, we believe that the resolution of these matters will not have a material adverse effect on our Consolidated Financial Statements.

Civil Reserve Air Fleet Program

We participate in the Civil Reserve Air Fleet program (the "CRAF Program"), which permits the U.S. military to use the aircraft and crew resources of participating U.S. airlines during airlift emergencies, national emergencies or times of war. We have agreed to make available under the CRAF Program a portion of our international aircraft during the contract period ending September 30, 2018. The CRAF Program has only been activated twice since it was created in 1951.

Employee Matters

Railway Labor Act

Our relations with labor unions representing our airline employees in the U.S. are governed by the Railway Labor Act. Under the Railway Labor Act, a labor union seeking to represent an unrepresented craft or class of employees is required to file with the National Mediation Board (the "NMB") an application alleging a representation dispute, along with authorization cards signed by at least 50% of the employees in that craft or class. The NMB then investigates the dispute and, if it finds the labor union has obtained a sufficient number of authorization cards, conducts an election to determine whether to certify the labor union as the collective bargaining representative of that craft or class. A labor union will be certified as the representative of the employees in a craft or class if more than 50% of votes cast are for that union. A certified labor union would commence negotiations toward a collective bargaining agreement with the employer.

Under the Railway Labor Act, a collective bargaining agreement between an airline and a labor union does not expire, but instead becomes amendable as of a stated date. Either party may request that the NMB appoint a federal mediator to participate in the negotiations for a new or amended agreement. If no agreement is reached in mediation, the NMB may determine, at any time, that an impasse exists and offer binding arbitration. If either party rejects binding arbitration, a 30-day "cooling off" period begins. At the end of this 30-day period, the parties may engage in “self help,” unless the U.S. President appoints a Presidential Emergency Board ("PEB") to investigate and report on the dispute. The appointment of a PEB maintains the "status quo" for an additional 60 days. If the parties do not reach agreement during this period, the parties may then engage in self help. Self help includes, among other things, a strike by the union or the imposition of proposed changes to the collective bargaining agreement by the airline. Congress and the President have the authority to prevent self help by enacting legislation that, among other things, imposes a settlement on the parties.

Collective Bargaining

As of December 31, 2017, we had approximately 87,000 full-time equivalent employees, approximately 19% of whom were represented by unions. The following table shows our domestic airline employee groups that are represented by unions.

Employee Group	Approximate Number of Active Employees Represented			Union	Date on which Collective Bargaining Agreement Becomes Amendable
Delta Pilots	13,234			ALPA	December 31, 2019
Delta Flight Superintendents (Dispatchers)	420			PAFCA	March 31, 2018
Endeavor Air Pilots	1,805			ALPA	January 1, 2024
Endeavor Air Flight Attendants	1,160			AFA	December 31, 2018
Endeavor Air Dispatchers	55			PAFCA	December 31, 2018

In addition, 192 refinery employees of Monroe are represented by the United Steel Workers under an agreement that expires on February 28, 2019. This agreement is governed by the National Labor Relations Act ("NLRA"), which generally allows either party to engage in self help upon the expiration of the agreement.

Labor unions periodically engage in organizing efforts to represent various groups of our employees, including at our operating subsidiaries, that are not represented for collective bargaining purposes.

Executive Officers of the Registrant

Edward H. Bastian, Age 60**:** Chief Executive Officer of Delta since May 2016; President of Delta (September 2007 - May 2016); President of Delta and Chief Executive Officer Northwest Airlines, Inc. (October 2008 - December 2009); President and Chief Financial Officer of Delta (September 2007 - October 2008); Executive Vice President and Chief Financial Officer of Delta (July 2005 - September 2007); Chief Financial Officer of Acuity Brands (June 2005 - July 2005); Senior Vice President - Finance and Controller of Delta (2000 - April 2005); Vice President and Controller of Delta (1998 - 2000).

Peter W. Carter, Age 54**:** Executive Vice President - Chief Legal Officer of Delta since July 2015; Partner of Dorsey & Whitney LLP (1999 - 2015), including co-chair of Securities Litigation and Enforcement practice group, chair of Policy Committee and chair of trial department.

Glen W. Hauenstein, Age 57**:** President of Delta since May 2016; Executive Vice President - Chief Revenue Officer of Delta (August 2013 - May 2016); Executive Vice President - Network Planning and Revenue Management of Delta (April 2006 - July 2013); Executive Vice President and Chief of Network and Revenue Management of Delta (August 2005 - April 2006); Vice General Director - Chief Commercial Officer and Chief Operating Officer of Alitalia (2003 - 2005); Senior Vice President- Network of Continental Airlines (2003); Senior Vice President - Scheduling of Continental Airlines (2001 - 2003); Vice President Scheduling of Continental Airlines (1998 - 2001).

Paul A. Jacobson, Age 46: Executive Vice President - Chief Financial Officer of Delta since August 2013; Senior Vice President and Chief Financial Officer of Delta (March 2012 - July 2013); Senior Vice President and Treasurer of Delta (December 2007 - March 2012); Vice President and Treasurer of Delta (August 2005 - December 2007).

Rahul Samant, Age 51: Executive Vice President - Chief Information Officer of Delta since January 2018; Senior Vice President and Chief Information Officer of Delta (February 2016 - December 2017); Senior Vice President and Chief Digital Officer of American International Group, Inc. (January 2015 - February 2016); Senior Vice President and Global Head, Application Development and Management of American International Group, Inc. (September 2012 - December 2014); Managing Director of Bank of America (1999 - September 2012).

Steven M. Sear, Age 52**:** President, International and Executive Vice President - Global Sales of Delta since February 2016; Senior Vice President - Global Sales of Delta (December 2011 - February 2016); Vice President - Global Sales of Delta (October 2008 - December 2011); Vice President - Sales & Customer Care of Northwest Airlines (June 2005 - October 2008).

Joanne D. Smith, Age 59: Executive Vice President and Chief Human Resources Officer of Delta since October 2014; Senior Vice President - In-Flight Service of Delta (March 2007 - September 2014); Vice President - Marketing of Delta (November 2005 - February 2007); President of Song (January 2005 - October 2005); Vice President - Marketing and Customer Service of Song (November 2002 - December 2004).

W. Gil West, Age 57: Senior Executive Vice President and Chief Operating Officer of Delta since February 2016; Executive Vice President and Chief Operating Officer of Delta (March 2014 - February 2016); Senior Vice President - Airport Customer Service and Technical Operations of Delta (February 2012 - February 2014); Senior Vice President - Airport Customer Service of Delta (March 2008 - January 2012); President and Chief Executive Officer of Laidlaw Transit Services (2006 - 2007).

Additional Information

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