The de Havilland Aircraft Company of Canada DHC-5 Buffalo was in essence, an enlarged turbo-prop development of the DHC-4 Caribou readily distinguished from its predecessor by its T-tail and larger engine nacelles.
The prototype DHC-5 Buffalo (US Army serial number 63-13686) was first flown on 9th April 1964 and followed an experimental turbo-prop conversion of the Caribou that had been first flown on 22nd September 1961 as the ‘DH Caribou II’. Like the Caribou, this was a rugged, short take-off and landing (STOL) aircraft ideally suited for operations from unprepared airfields. The Buffalo offered twice the payload capacity of the Caribou, combined with superior short field performance. Capacity was up to 41 troops or some 18,000 lb of cargo payload and power was provided by two 3,133 hp GE CT64 turboprops.
Four test aircraft (designated YAC-2, later C-8) were delivered to the US Army. These were followed by 15 CC-115 transports for the RCAF.
A new variant, the DHC-5D, entered production in 1974 and achieved export sales success with small numbers being sold to a number of countries, including Abu Dhabi (five), Brazil (24), Cameroon (five), Chile (one), Zaire (DRC) (three), Ecuador (four), Egypt (10), Indonesia, Kenya (10), Mauretania (two), Mexico (two), Oman (three), Peru (16), Sudan (four), Tanzania (six), Togo (two), and Zambia (seven).
In total 126 DHC-5 Buffaloes were built (construction numbers c/n 1 to c/n 126) with the last production example being delivered to the Kenyan Air force in December 1986.
The de Havilland DHC-5E Transporter was a projected civil transport variant, designed for up to 48 passengers. Although a prototype / demonstrator was built, the programme was halted after a landing accident to this aircraft at the Farnborough Air Show in 1984.
The last Buffalos in active military service were six used by No. 442 Transport and Rescue Squadron of the Royal Canadian Air Force (RCAF). These were retired in 2022, after 55 years of operational service.