In 1936, Orville Wright flatly declared that the helicopter would never be practical. Three years later, Igor Sikorsky began proving Wright wrong. The helicopter required two decades more to come into everyday use, but it did. Perhaps the tiltrotor just needed more time to change the world.
--Richard Whittle, The Dream Machine: The Untold History of the Notorious V-22 Osprey.
The sad nature of the aviation business is that accidents happen, even to the best of pilots. Based on Jamie McIntyre's coverage of the US Air Force's investigation of a V-22 Osprey crash last month, it's safe to say the same occurred here as well.