The UH-1 Iroquois, commonly known as the "Huey," is a multipurpose military helicopter and was developed from 1955 US Army trials with the Model 204. The initial designation of the HU-1 (helicopter utility) led to its nickname, Huey. It was first used by the military in 1959 and went into tri-service production in 1962 as the UH-1. The last were produced in 1976 with more than 16,000 made in total, of which about 7,000 saw use during the Vietnam War.