You probably all know what a tiltrotor is. But do you know where the idea came from? Why did someone invented an aircraft “which generates lift and propulsion by way of one or more powered rotors mounted on rotating engine pods or nacelles usually at the ends of a fixed wing.” ?
We could think that someone thought of that because it combines helicopters vertical lift capability with planes speed and range, definitely great advantages of each type of aircrafts.
In fact, it seems like the first design similar to actual tiltrotors was made in 1930 by George Lehberger, but it never left the drawing table. Later on, during World War II, a prototype was built by the Germans, but it never actually flew. It was called the Focke-Achgelis FA-269.
In 1947, the Transcendental 1-G was developped, and flew for the first time in 1954. In July 1955, the prototype crashed and even if it got destroyed, the pilot was able to walk away from the crash.
Shortly after, the Transcendental Model 2 was created, but the funding was withdrawn by the US Air Force, who decided to fund the Bell XV-3 instead, which flew until 1966. The XV-3 encountered a major problem with its design: since the engine was mounted inside the fuselage, very long drive shafts were needed, causing a lot of vibrations, as well as other issues.
The XV-15 was developed by Bell Helicopter in 1972, with funding from NASA and the US Army. The aircraft was used to research the possible use of the tiltrotor for military and civil applications.
In 1981, Bell teamed up with Boeing Helicopter to develop the V-22 Osprey, which was used by the US Air Force and Marine Corps. The V-22 performed missions such as troop or cargo transport, special operations, amphibious assaults, and search and rescue missions. It also flew at major airshows, including the famous Paris Air Show. However, even if the Congress agreed that the V-22 was polyvalent and could be useful for military and civilian uses, it also questioned its affordability. The Congress stated that the cost of the aircraft was not justified by its performance, especially since they considered the V-22 as being too risky due to several reported accidents.
Bell also worked with AgustaWestland to develop the Bell/Agusta BA609, which later became the AW609, The AW609 can seat up to 9 people at twice the speed and range of typical helicopters.
On their website, AgustaWestland describes it as the “next generation of aircraft transport for civil (both private and commercial operators), government and para-public roles.”
Do you agree with AgustaWestland? Do you think tiltrotor could replace helicopters ?