Delta Air Lines fleet

As of October 2017, the Delta Air Lines mainline fleet comprises 851 aircraft in service, making it one of the largest airline fleets in the world. Before merging with Northwest Airlines in 2009, Delta Air Lines operated an all-Boeing and McDonnell Douglas fleet; it incorporated Northwest's Airbus aircraft into its fleet following the merger and subsequently ordered further Airbus types. Delta is known for its policy of generally buying older generation or used aircraft and for continuing to fly aircraft for 20-30 years, much longer than most other major airlines. As such, it has one of the oldest fleets of any American airline, with an average fleet age of 17 years as of 2017. Fellow U.S. legacy carriers American Airlines and United Airlines have much younger fleets; as of December 29, 2016, American had an average fleet age of 10.3 years, while United had an average fleet age of 14.1 years.

As of October 16, 2017, Delta's fleet consists of 851 Airbus, Boeing, and McDonnell Douglas aircraft. Delta's 483 Boeing aircraft make up about 60% of its fleet, while its 193 Airbus aircraft and 175 McDonnell Douglas aircraft each make up about 20%. Delta's narrow-body aircraft comprise about 82% of its fleet at 701 aircraft, while its 150 wide-body aircraft comprise the remaining 18%.

Delta operates the largest fleets of the Boeing 717, the Boeing 757, the Boeing 767, the McDonnell Douglas MD-80, and the McDonnell Douglas MD-90 worldwide. It is one of only two airlines worldwide operating the Boeing 767-400ER (the other being United Airlines), and the only airline still operating the MD-90 in the world. It is also one of only two passenger airlines in the United States operating the Boeing 747-400.

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