Essential to emergency services and the military worldwide, the helicopter has come a long way since the first autogiros were designed by Juan de la Cierva in the 1920s. Helicopters contains detailed features on more than 120 rotorcraft from around the world. Each helicopter is covered in detail, with feature boxes outlining its development, technical specifications, performance data and variants. Unique graphics allow the reader to compare specific features like range, firepower and troop-carrying capacity to those of other rotorcraft of the same type.