The US Army requirement for a light utility helicopter was formulated after the Korean War. Bell's Model 204 design won a competition in 1955, and was given the military designation H-40, later renamed the HU-1 Iroquois. The original design called for a helicopter that could be used for transport, airborne battlefield command and control, medical evacuation, fire support co-ordination and search and rescue. Later its missions would be expanded to include troop insertion/extraction, armed escort and special operations. This title details all the technological background behind the development and use of the Huey ?Slick? in Vietnam, as well as covering all the major uses that this transport aircraft was put to.