DC-9 / ContinentalDouglas DC 9 Continental Airlines model. The DC 9 was developed as a short range airliner complementing the much larger DC 8. Development was launched on April 8 1963, with a launch order from Delta following soon after. The DC 9 was an all new design, featuring rear fuselage mounted engines, a Ttail, moderately swept wings and seats for up to 90 passengers. Construction of the prototype began in July 1963 and the first flight occurred on February 25