What began as a successor to the superb C-7 Caribou, the de Havilland Canada CC-115 Buffalo, ended up being the unfortunate victim of US inter-service rivalries, mainly the transfer of all fixed-winged US Army aircraft to the USAF in 1967. Therefore, despite winning the original Army requirement for a new STOL aircraft, the USAF decided not to award the contract being considered sufficiently equipped with transports (none of which even remotely compared in terms of STOL capability). As a result, the Buffalo was ordered by the Canadian RCAF and, as proof of its outstanding capabilities, was ordered by nearly 20 other foreign operators. The CC-115 was designed with the same high-wing configuration as its predecessor but featured turoprop rather than piston engines as well as a new T-tail. Production ended in 1986 with units in service today mostly for search and rescue.

The DHC-5 was first flown on 9 April 1964 and were delivered to the US Army as the YAC-2 which was later changed to CV-7A after 1962, and C-8A by the USAF. Given the lack of US orders, they entered service with the RCAF as the CC-115 (DHC-5A). Other variants include the export DHC-5B (Brazil), and the DHC-5D (to Egypt but later sent to numerous other air forces) with new engines.