DeHavilland Canada (Viking Air) DHC-5 Buffalo
With the United States Air Force looking for a tactical STOL aircraft like the DHC-4 Caribou but with more payload, DeHavilland Canada took the latter as starting point for a new design. This became the DHC-5 Buffalo. The DHC-5 is basically an enlarged DHC-4 with a T-tail and turboprop engines instead of radial piston engines. What remains from the Caribou are the long main landing gear legs retracting forward in the engine nacelles, the nose including cockpit windows, large oval cabin windows and the upsloping rear fuselage.
Viking Air purchased the type certificate for the DHC-5 in 2006 (together with all models from DHC-1 until DHC-7). It planned a modernised version (DHC-5NG), but this is yet to see the light.
The versions of the Buffalo mainly only differ by exact engine type. Therefore they cannot be distinguished on the outside.
DHC-5 (YAC-2, CV-7A & C-8A)
As the DHC-5 was developed in response to a US Army order, the first version is the one that was delivered to the US Army as (Y)AC-2. Later is was re-designated CV-7A and C-8A. Only four were built owing to a dispute between the US Air Force and US Army about operating large transport aircraft.
The DHC-5A is essentially the same as the DHC-5, but then certified by the Canadian authorities. This version is used by the Canadian air force as search and rescue aircraft, designated CC-115. It has observation windows in the emergency exits after the wings as recognition point. The Brazilian air force also operated this version under designation C-115.
This version features more powerful T64 engines, but is for the rest the same as the DHC-5A.
DeHavilland Canada also tried to sell the DHC-5 on the civil market. This was designated DHC-5E, with marketing name Transporter. Just one demonstration aircraft was built.
Confusion possible with
DeHavilland Canada DHC-4
The Buffalo is clearly derived from the DHC-4 Caribou. Basically, you could regard the DHC-5 as a DHC-4 with a T-tail and turboprop engines, although there are more differences.
It is from the same company with the same basic configuration, but the DHC-8 is still significantly different. It has fewer cockpit windows, smaller and rectangular cabin windows, a dorsal fin, a backward retracting main landing gear and no rear loading ramp.
Quiet Short-Haul Research Aircraft
Under supervision of NASA a Buffalo was modified as Quiet Short-Haul Research Aircraft (QSRA). It received a new wing with four jet engines on top instead of two turboprops underneath. (photo NASA/WikiMedia)
Augmented Wing Jet-flap STOL Research Aircraft
Another Buffalo modification was the Augmented Wing Jet-flap STOL Research Aircraft. This has two jet engines under the wings in large nacelles. The wing span was shortened and the wings had leading edge slats. Air from the ducted engines was blown over the wings to increase effectivity. (photo NASA/WikiMedia)