The Probert Encyclopaedia of Aircraft

DC-9

The Douglas DC-9 is a series of American short/medium-haul low-wing cantilever monoplane commercial airliners initially designed to carry 68 first-class passengers over medium ranges at speeds and in comfort equivalent to those of the larger DC-8 jetliner. The DC-9 Series 10, carrying 90 passengers began service in 1965. The Series 20 in 1968, the 115 seat Series 30 in 1967, the 125 seat Series 40 in 1968, the 139 seat Series 50 in 1975, and the final model, the Super 80 with room for 172 passengers in 1980.
Research DC-9