flaps enclosing a venturi-shaped passage. The usual turboprop engines were replaced with Rolls-Royce Spey 801 SF (Split Flow) bypass engines with a new bypass duct which separated the hot and cold flows to provide both propulsion and augmentor airflow to the powered lift system. The hot flow was directed through Pegasus-engine swivelling nozzles to ensure it deflected with the flap downwash. The cold flow was directed into the flap venturi and entrained extra airflow. Beginning in 1972 with its first flight in this experimental configuration, this aircraft was used jointly by the NASA Ames Research Center and the Canadian Department of Industry, Trade and Commerce for STOL research. Quiet Short-Haul Research Aircraft In the late 1970s and early 1980s, NASA used another C-8A Buffalo in the Quiet Short-Haul Research Aircraft program. Boeing designed and installed an experimental swept, supercritical wing incorporating a boundary layer control system. Instead of the standard engines, this aircraft was powered by four prototype Avco Lycoming YF102 high-bypass turbofan engines (originally from the Northrop YA-9 program) mounted above the wing to take advantage of the Coandă effect. In 1980, this aircraft participated in carrier trials aboard USS Kitty Hawk, demonstrating STOL performance without the use of catapults or arrestor gear. The aircraft is currently stored at NASA's Ames Research Center in Mountain View, California. Air Cushion Landing System Aircraft After demonstrations by Bell aircraft using a Lake LA-4 light amphibian with Air Cushion Landing Gear the development of this type of gear was pursued in a joint effort between the USAF and the Canadian Government by retrofitting a similar system to a medium cargo transport, a Buffalo. The air supply to the cushion was provided by an air supply package consisting of a PT6F-70 and two-stage axial flow fan under each wing. The aircraft also had underwing combination floats/skids. Variants DHC-5 Buffalo Originally designed as a twin-engined STOL tactical, utility transport aircraft for the US Army. Original US Army designation AC-2. Utility transport aircraft for the Brazilian Air Force, Royal Canadian Air Force and Peruvian Air Force. Canadian designation CC-115. DHC-5B Proposed version, powered by two General-Electric CT64-P4C turboprop engines. Not built. DHC-5C Proposed version, powered by two Rolls-Royce Dart RDa.12 turboprop engines. Not built. DHC-5D Improved version, powered by two 2,336 kW (3,133 shp) General Electric CT64-820-4 turboprop engines. DHC-5E Transporter Civil transport version. NASA / DITC C-8A AWJSRA One C-8A aircraft converted into an