The C-9B is a convertible passenger/cargo version of the civil series 30 DC-9, a streeched devlopment of the orginal Douglas DC-9 transport. The Skytrain II name carries the traditions of the famed DC-3 Skytrain of WWII. The C-9B diifers from the standard airline configuration in having a large cargo door on the port side of the forward fuselage, along with other necessary cargo-handling features. All other details are essentially the same as airline models.

VARIANTS

C-9A Nigtingale - 23 aeromedical evacuation aircraft for the USAF with deliveries starting in 1968.
C-9B Skytrain II - 22 convertible passenger/transport versions for the US Navy and 2 for the US Marines devlivered from 1973 to 1976. An additional five C-9s were converted from passenger configured DC-9s.
VC-9C - 3 executive transport aircraft for the USAF delivered in late 1976.
C-9K - 2 aircraft for the Kuwaite Air Force.