British Army Training Unit Suffield (BATUS) is situated in Alberta, amidst the dry, semi-barren, rugged and undulating Canadian prairie, where the Blackfoot, Cree and Sioux tribes once hunted buffalo and engaged in combat. The training area measures 39 miles west to east and 32 miles north to south, with a total area of 1038 square miles. It is slightly larger than Luxembourg and seven times the size of Salisbury Plain. The prime purpose of BATUS is to provide realistic all-arms, battle group manoeuvre training with live firing. Four major `Prairie Storm' exercises are held every year between April and October, involving infantry, armour, artillery, aviation and support arms. Up to 2500-3000 personnel may be on the ground, along with as many as 1200 vehicles of all types from Main Battle Tanks to 4x4s. BATUS was formally established in 1972; making up for the loss of training areas in Libya in 1969. Right from the start it was envisaged that there would be an Army Air Corps element. The original aircraft were replaced by Westland AH1 Gazelles in 1977, they continue in service 40 years later with 29 (BATUS) Flight, which is now part of 5 Regiment Army Air Corps.