Beating Gravity - Bell Boeing Model 901 (V-22 Osprey)

Bell and Boeing Vertol joined together in the early 1980s to develop from the Bell XV-15 an aircraft to satisfy the Joint Services Advanced Vertical Lift Aircraft (formerly JVX) program. The Bell Boeing Model 901 combined the vertical lift capabilities of a helicopter with the fast-cruise effectiveness of a fixed-wing turboprop aircraft, and was designated V-22 Osprey.

It was designed around two turboshafts located at the tips of the slightly forward-swept wing, each driving three-bladed proprotors which could be swivelled through 97.5°.

A full-scale development contract was awarded in June 1985 for six prototypes and a number of static test airframes.

Initial joint-service requirements were for 913 V-22s, comprising 552 MV-22A assault aircraft, each able to transport up to 24 fully armed troops, as CH-46 for the USMC; 231 similar machines for the US Army; 80 CV-22A machines for the USAF for long-range transport of special forces; and 50 HV-22A machines for the US Navy's combat Search-and-Rescue, special warfare and fleet logistical support roles. The US Navy also anticipated a future need for another 300 aircraft optimised for an anti-submarine role.

For shipboard storage the wing of the V-22 was able to rotate to lie fore-and-aft over the fuselage, with the nacelles folding in parallel. Bell flew the first test aircraft on 19 March, 1989; the first transition from helicopter to wingborne flight followed, on 14 September 1989. On 9 August 1989 and 9 May 1990 the second and third machines followed. Two more were produced by June 1991.

A sixth was not completed. The fifth aircraft was badly damaged in a non-fatal accident on its first flight. A more serious setback was the crash of the fourth Osprey on 21 July 1992, killing all seven persons on board. Already under close political and financial review, the project faced cancellation but survived, with tests resuming in June 1993.

Meanwhile, the USMC reduced its initial order to 300 before raising it to 425 and the competition was opened to other aircraft types. The superiority of the V-22 was recognised, and production was finally authorised in September 1994, the initial production model being the MV-22A for USMC delivery in mid-1999 and initial operational capability following in 2001.

Comment contributed by Phil West:
"From what I understand, there are a lot of things wrong (with the Osprey) - capacity too small, unstable, terrific down wash, not robust enough (often its called a 'hanger queen'). It's killed quite a few pilots and marines already and most are grounded. One of the problems, compared to the earlier attempts on this line, is that the engines pivot but the wing doesn't, which blocks the downward thrust (so more is needed) and increases air pressure above the wing (negative lift!). And no one has ever satisfactorily answered my question - what happens if the rotors get stuck in the horizontal - how do you land?"

More Osprey links:

More about the V-22 Osprey from the Smithsonian Air & Space magazine website.

Waiting for the Next V-22 Crash at www.g2mil.com

Mike Sparks also has a page on the Osprey at www.geocities.com/equipmentshop/trail2aircraft.htm

Russian V-22 site