Test flights of U.S. MV-22 Osprey military aircraft, initially planned for later this month, won't start until early September at the soonest, according to government sources.
More time is required to verify the causes of two recent crashes involving the tilt-rotor transport aircraft, the sources said Tuesday.
Lt. Gen. Kenneth Glueck, commanding general of the Third Marine Expeditionary Force, meanwhile said Tuesday that actual deployment of the aircraft in Okinawa will be "sometime after" Sept. 9, when residents of Okinawa have scheduled a protest rally.
Facing strong local opposition to the deployment, Tokyo and Washington have agreed that the U.S. military will not conduct test flights until after investigations into the recent accidents abroad are wrapped up and safety is confirmed.
Twelve Ospreys remain at the U.S. Marine Corps' Iwakuni Air Station in Yamaguchi Prefecture after being unloaded there July 23. They are to undergo safety testing prior to their deployment at the Futenma air base in Ginowan, Okinawa.
Glueck said the process to verify safety will likely take place until early September and then "another week or 10 days" before starting to move the aircraft to Futenma.
A total of 24 Ospreys are to be deployed at Futenma by 2014 to replace aging CH-46 helicopters. The marines plan to start full operations of the Osprey in Okinawa in October.