Douglas DC-9-50s

The McDonnell Douglas DC-9-50 was the largest and longest variant of the DC-9 series. The development of this rear-engine aircraft family began in the 1950s when Douglas Aircraft Company sought to create a medium-range plane to complement its high-capacity DC-8 models.

The first DC-9 prototype took flight on February 25, 1965, followed by a fleet of four test aircraft. After receiving its airworthiness certificate on November 23, 1965, it entered commercial service with Delta Air Lines on December 8. In 1967, Douglas merged with McDonnell, leading to the aircraft being rebranded as the McDonnell Douglas DC-9.

Designed with rear-mounted engines to enhance aerodynamics, the DC-9 was intended to accommodate different passenger capacities based on airline requirements. The first extended version, the DC-9-30, debuted with Eastern Air Lines in 1967, serving as an alternative to the Boeing 737. The DC-9-40 followed in 1968, adding six feet six inches to its length and increasing capacity to 125 passengers.

Responding to airline demand for a larger twin-engine narrowbody aircraft, McDonnell Douglas developed the DC-9-50, featuring enhanced engines, an upgraded cabin, and a higher maximum takeoff weight. A notable design element was its thrust reversers, angled inward by 17 degrees, originally introduced for Air Canada and later applied to earlier DC-9 models.

With a capacity of 130 passengers, the DC-9-50 entered service with Hawaiian Airlines 1975. The aircraft ultimately, replaced the DC-9-10s aircraft for neighboring island service flights.

ModelDC-9-50
Length133 ft 7 in
Height28 ft 9 in
Wingspan93 ft 4.2 in
Engine2 x P&W JT9D-17 (71,2 kN) turbofans
Maximum Take-off Weight121,000 lbs
SpeedMach 0.84 (644 mph)
Ceiling35,000 ft
Range1,300 nm
Crew2
Passengers139

 

Reference

  1. Walker, Steven & Finlay, Mark. (Mar 27, 2024) McDonnell Douglas DC-9-50: The Rear-Engined Family’s Longest Variant. Simple Flying. https://simpleflying.com/mcdonnell-douglas-dc-9-50-story/