Press Release

Fighting with Failures Series: Case Studies of How the Pentagon Buys Weapons; V-22 Osprey Tilt-Rotor Aircraft

The V-22 Osprey is a tilt-rotor aircraft that takes off and lands like a helicopter, but converts to fly as a turboprop aircraft. It is intended to replace current Marine Corps medium-lift assault helicopters.

Short Cuts on the Way to Acquisition:

  • The original plan to test the V-22 in helicopter and aircraft conversion modes at various rates of descent, speeds, and weights was cut by more than two-thirds in order to meet cost and schedule concerns. This segment of developmental testing would have offered considerable insight into the V-22's susceptibility to a sudden loss of controlled flight, known as Vortex Ring State (VRS) - responsible for one of the four crashes that have killed a total of 30 Marines.
  • The DOD planned to go ahead with full-rate production, not having adequately tested and evaluated the V-22 to determine whether new technology could meet necessary requirements; whether the design would work as required; or whether the design could be produced within cost, schedule, and quality targets.
  • The April 1997 decision to proceed with low-rate initial production of the V-22 was based on limited testing of an earlier design targeted for cancellation from 1989-1992 by then-Secretary of Defense Richard Cheney. As a result, the General Accounting Office warned in an October 1997 report that future production decisions should be based on more realistic testing.


  • A number of tests were waived in 1999 for the V-22 operational evaluation due to the aircraft’s inability to meet specified requirements. The inability to properly test a number of capabilities raises doubts about the operational effectiveness of the V-22.According to the Department of Operational Testing and Evaluation, the V-22 is not operationally suitable, or battle-worthy. Operational testing has shown that the V-22 did not achieve a number of established suitability thresholds and failed to out perform the CH-46, the aircraft it is slated to replace. While the CH-46 had a full mission capable rate of 74 percent from 1995-1999, during testing the V-22 was only mission capable 4-31 percent of the time.
  • The V-22 is particularly vulnerable to Vortex Ring State. A rapid rate of descent coupled with a failure to maintain adequate forward speed can cause one of the aircraft’s two proprotors to stall while the other proprotor remains fully functional, causing the aircraft to sharply roll into the side that stalls. At low altitudes there is little opportunity for recovery. Currently there are no known indicators that could alert the pilot to when the aircraft approaches a flight region known to be susceptible to vortex ring state.
  • The downward force from the V-22 proprotor blades while in the hover mode (referred to as down wash) is a continuing concern. This intense rotor downwash means the aircraft must hover at higher altitudes - 65-75 feet - as assault troops exit the V-22 by sliding down ropes, which exposes both the aircraft and deploying personnel for longer periods of time. While landing in the desert, downwash can produce “brown-out” conditions as sand is blown, making it extremely difficult to land at night while using night-vision devices.
  • At night, external loads prevent the radar altimeter from effectively registering the distance between the aircraft and the ground. All night operations should be conducted with an effective radar altimeter.
  • The V-22 has not been given clearance to conduct air combat maneuvering. As a result, the operational evaluation was unable to examine the effect air combat maneuvering would have on the aircraft’s survivability.
  • A defensive weapon system has yet to be developed for the V-22.
  • Military requirements call for the V-22 to handle internal payloads weighing as much as 8,000 pounds. During its operational evaluation the aircraft was limited to handling 2,000 pound payloads.
  • The V-22 has not been adequately tested in icing conditions. Unlike conventional rotary-wing aircraft, the V-22 converts to fly as a conventional aircraft at higher altitudes. Therefore, it is imperative that it be able to fly in the presence of icing conditions.
  • The cockpit and fuselage should restrict the entry of nuclear, biological, and chemical agents into the aircraft’s interior. However, seals intended to retain the integrity of the interior are faulty. This capability was not tested during the V-22's operational evaluation.
  • V-22 communication capabilities are insufficient to self-deploy over large bodies of water or land at some airports without escort aircraft. Absent improved communication capabilities, the V-22 will have to rely on escorts to relay emergency and positioning information to applicable controlling agencies.
  • Total Number of Aircraft: 458; Total Program Cost: $41.15 billion; Average Unit Cost: $89.7 million.

Project On Government Oversight’s Fighting with Failures Series documents Pentagon shortcuts in testing and operational requirements that have resulted in weapons that do not work, that waste taxpayer dollars, or that are not suitable for combat.

Sources: Combined Operational Test & Evaluation and Live Fire Test and Evaluation Report on the V-22 Osprey, Director, Operational Test & Evaluation, November 17, 2000; V-22 Osprey Tilt-Rotor Aircraft, Congressional Research Service, April, 12 2000; V-22 Cost and Capability to Meet Requirements are Yet to be Determined, GAO/NSIAD-98-13, October 1997; Presentation To The V-22 Blue Ribbon Panel, GAO-01-369R, February 2001; Fiscal Year 2000 Annual Report, Director, Operational Test & Evaluation, March 2001.