In 1951 the Malayan Scouts (SAS) had successfully recruited enough men to form a regimental headquarters, a headquarters squadron and four operational squadrons with over 900 men. The regiment was tasked to seek, find, fix and then destroy the terrorists and prevent their infiltration into protected areas. Their tactics would be long-range patrols, ambush and tracking of the terrorists to their bases. The SAS troops trained and acquired skills in treejumping, which involved parachuting into the thick jungle canopy and letting the parachute catch on the branches; brought to a halt, the parachutist then cut himself free and lowered himself to the ground by rope. Using inflatable boats for river patrolling, jungle fighting techniques, psychological warfare and booby trapping terrorist supplies. Calvert was invalided back to the United Kingdom in 1951 and replaced by Lieutenant-Colonel John Sloane.