This book describes in superb pictures and text the fascinating genre of tilt rotor airplanes. Since the first helicopters flew, attempts have been made to create a link between the mobility of the rotorcraft and the speed of the winged airplane. At first these attempts failed simply because of constructive difficulties, since the technology had not advanced far enough. The progressive development, though, created in the past decades new possibilities, and thus led to the V-22 Osprey, which has meanwhile been produced in series and is used by the U.S. forces. A civilian model, the Bell/Agusta BA 209, will soon be introduced commercially.