McDonnell Douglas DC-9

The McDonnell Douglas DC-9 is an American twin turbofan, narrow-bodied, short to medium range airliner. It first flew on February 25, 1965, entering service in December with Delta Air Lines. Designed to operate from short runways with less ground infrastructure. In US military service, the type received the designation of C-9. Manufactured in several variants, production ended in 1982 with 976 built. Developed into the MD-80, MD-90, MD-95 and finally the Boeing 717.

Airframe construction is mainly aluminium alloy with a semi-monocoque fuselage with built-in airstairs; the low mounted wings and T-tail assembly are of cantilever design with sweep back.  The retractable undercarriage is a tricycle type mount to the wing roots,  folding inwards into the fuselage; the steerable nose wheel retracts rearward. The flight crew consists of a pilot and copilot, and the passenger cabin typically seats 80 to 139 passengers depending on variant and seating arrangement.

It is powered by two Pratt & Whitney JT8D low-bypass turbofan engines mounted on pylons, one on each side of the rear fuselage. The DC-9-30 has a cruise speed of 907 km/h (564 mph), a maximum speed of 926 km/h (575 mph), a 10,670 m (35,000 ft) service ceiling and a range of 3,095 km (1923 mi).