The United States Marine Corps resumed testing of the controversial V-22 Osprey this week, two years after the aircraft was grounded following two fatal accidents. Four Marines were killed in North Carolina and 19 others died in Arizona when their Ospreys malfunctioned and crashed. Several military watchdog organizations say the aircraft, which takes off and lands like a helicopter yet flies like a conventional plane, is too dangerous.

Spokespersons for the Marines as well as the aircraft's manufacturers, Boeing and Bell Helicopters Textron, insist major alterations have been made to the Osprey's hydraulic and control systems that ensure they are "returning a safe and operational aircraft to the fleet." In October 2001, Boeing and Bell agreed to pay more than $1 million to the family of Lt Col. Keith Sweaney, the Marine officer who piloted the Osprey that crashed in North Carolina.