• Manufacturer: Bell
  • Model: Sioux AH1
  • Year built: 1964
  • Aircraft Type: Rotary wing single engine
  • Number of Seats: Pilot plus 2
  • Number of Engines: 1
  • Engine Type: Reciprocating
  • Engine Manufacturer and Model: Lycoming TVO-435-A1A
  • Civil registration: G-CICN
  • Military registration: XT131

The Bell 47 first flew on 8th December 1945 and entered service with the US military in 1946. In 1949 it held the altitude record for a helicopter with a height of 18,500 feet. It went on to serve with much success during the 1950s in Korea (as featured in the television programme M*A*S*H) and the 1950s to 1970s in Vietnam.

The Italian manufacturer Agusta, produced the first 30 aircraft, followed by Westland Helicopters in Yeovil who built a further 250. These aircraft were all designated Sioux AH1. A further 15 were built as AH2 and these went to the RAF for use as training helicopters equipped with a different radio fit and extra flight instruments.

The Sioux has a 6-cylinder Lycoming TVO 435-B1A engine which is turbocharged and produces 270 bhp. It cruises at around 70 knots and has a maximum speed of 91 knots / 105 mph. This gives the Sioux a range of 250 nautical miles and an endurance of 2 hours 30 mins.

The Sioux in Army Service

The Sioux AH1 entered British Army service In 1964. The helicopter proved extremely versatile for the Army and was operated in many roles in the UK, West Germany, the Middle East and the Far East. These roles included: Air Observation Post (AOP) for the Royal Artillery, reconnaissance, casualty evacuation, light liaison, underslung loads, operations from ships, pilot training and photography. The aircraft remained in Army Air Corps service until June 1977.

The Historic Army Aircraft Flight’s Sioux is XT131. This aircraft was the last to be built by Agusta and arrived at Middle Wallop in 1964 as a training aircraft. It has remained there ever since.