Stretched, enlarged wing and powered by higher bypass Pratt & Whitney JT8D-200 engines, the aircraft program was launched in October 1977.

The larger variants (MD-81/82/83/88) are 148 ft (45.1 m) long to seat 155 passengers in coach and, with varying weights, can cover up to 2,550 nautical miles [nmi] (4,720 km; 2,930 mi).

The DC-9 series, the first generation of the DC-9 family, entered service in late 1965 and became a commercial success with 976 units built when production ended in 1982.

The first Series 80, DC-9 line number 909, made its first flight on October 18, 1979, as the Super 80,[6] which then became the preferred designation for the newly developed aircraft family.

[note 1] Although two aircraft were substantially damaged in accidents, flight testing was completed on August 25, 1980, when the first variant and respectively production model, the JT8D-209-powered Series 81, was certified under an amendment to the FAA type certificate for the DC-9.

[14] The first conversion was undertaken on an ex-American Airlines MD-82 aircraft (FSN 49470 built in 1987), which was used as a test-bed for the supplemental type certificate.

AEI was the first and solely firm authorized by Boeing to receive the STC, ST02434LA, for the longer variants of the MD-80 series from the FAA in February 2013.

[19] In the said STC, EAT MD-87 air tankers are required to drop retardant with landing gear down to prevent stalling.

In early 2017, EAT petitioned the FAA for an exemption from this requirement, 14 CFR 25.201(b)(1), and requested a "Flaps 40/Landing Gear Up" configuration while dropping, but on June 28, 2017, that exemption was denied with the reason given by the FAA that it would have allowed aerial firefighting retardant drops in a configuration that does not fully meet the stall characteristics requirements on the modified DC-9-87 (MD-87) aircraft.

Chang,[21] president of a McDonnell Douglas subsidiary, signed an agreement for joint production of MD-80s and MD-90s in the People's Republic of China.

[22] Upon cancellation of the co-production program, China refused to return the tooling used to McDonnell Douglas, and subsequently used it and the fuselage cross-section design in what became the Comac ARJ21 regional jet.

As a result of the decline in the air traffic and a slow market response to the MD-90, MD-80 production was reduced, and 84 aircraft were handed over in 1992.

By 1989, however, lack of airline orders for the UHB derivatives caused McDonnell Douglas to return to the IAE V2500 engines to launch its MD-90 series aircraft.

The "main improvement" was the installation of Pratt & Whitney JT8D-290 engines (never built) with a 1.5 in larger diameter fan that would allow for a 6 dB reduction in exterior noise.

A Honeywell wind-shear computer and provision for an optional traffic-alert and collision avoidance system (TCAS) were also to be included.

[11] The MD-90 was developed from the MD-80 series and is a 5-foot-longer (1.5 m), updated version of the MD-88 with a similar electronic flight instrument system (EFIS) (glass cockpit), and improved, and quieter IAE V2500 high-bypass turbofan engines.

Delta Air Lines flew the final MD-90 passenger flight on June 2, 2020, marking the retirement of the type.

The aircraft derivative retains the configuration of two rear fuselage-mounted turbofan engines, a T-tail, and has cockpit, avionics and aerodynamic upgrades.

The airliner is designed for frequent, short-haul flights for up to 172 passengers depending on airplane version and seating arrangement.

[citation needed] American Airlines was the first US major carrier to order the MD-80 when it leased twenty 142-seat aircraft from McDonnell Douglas in October 1982 to replace its Boeing 727-100s.

[48] In February 2013, Commercial Jet Inc. (CJI) delivered the first AEI MD-80SF, an MD-82SF (the prototype), to Everts Air Cargo, the launch customer of the MD-80SF passenger-to-freighter conversion program by the Aeronautical Engineers Inc.

The MD-80SF has a low deck height that allows it to load cargo from a pickup truck when needed, which is not possible on a Boeing 757 freighter.

EAC specializes in transporting freight and mail in Alaska and uses its MD-80SF fleet to supply on demand charter service operations throughout the United States, Canada, Mexico, and Caribbean Islands.

That is well short of the 19,000+ gallon capacity of the 747 Global Super Tanker, but the MD-87 is much more cost-effective to operate and can utilize more austere fields with shorter runways.

The new version featured a higher MTOW (149,500 lb (67,800 kg)), while the JT8D-217As had a guaranteed take-off thrust at temperatures up to 29 °C (84 °F) or 5,000 ft (1,500 m) altitude.

In January 1985, McDonnell Douglas announced it would produce a shorter-fuselage MD-80 variant, designated MD-87 (DC-9-87), which would seat between 109 and 130 passengers depending upon configuration.

The MD-88 was the last variant of the MD-80, which was launched on January 23, 1986, on the back of orders and options from Delta Air Lines for a total of 80 aircraft.

The MD-88 is, depending on specification, basically similar to the MD-82 or MD-83 except it incorporates an EFIS cockpit instead of the more traditional analog flight deck of the other MD-80s.

The wind-shear warning system was offered as a standard option on all other MD-80s and has been made available for retrofitting on earlier aircraft including the DC-9.

[68] On May 30, 2019, AerSale, a global supplier of mid-life aircraft, engines, and maintenance, repair, and overhaul (MRO) services, announced that it had signed a contract with Aero Air/ Erickson Aero Tanker to build the sixth MD-87 firefighting air tanker, beginning conversion on April 1, 2019, at AerSale's MRO facility in Goodyear, Arizona.