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Bell XV-15 Tilt Rotor Research Aircraft
The XV-15 Tilt Rotor technology demonstrator was the culmination of efforts begun in the early 1950's to produce an aircraft that could take off, land, and hover like a helicopter, but with the speed of an airplane. The rotor pylons tilt from vertical to horizontal, to eliminate the speed barriers imposed on conventional helicopters by retreating-blade stall.
This is the second of two XV-15's built by Bell under a join NASA/Army program. From 1979 to 2003, it logged 700 hours in testing and demonstrated operations under a wide range of conditions. Its success encouraged Bell and the Marine Corps to develop the scaled-up MV-22 Tilt Rotor as a replacement for Marine transport helicopters. In association with Agusta Aerospace, Bell also developed the Model 609 civil Tilt Rotor, using experience gained from the XV-15. |