The Self-Defense Forces held a joint disaster drill Friday with U.S. forces in Kochi Prefecture but without the U.S. Marine Corps' MV-22 Ospreys, which were supposed to take part.
The tilt-rotor aircraft were excluded from the drill due to bad weather and poor visibility, according to the Defense Ministry. The troop transports, which take off and land like helicopters but can cruise like fixed-wing aircraft, are deployed at the U.S. Futenma air station in Ginowan, Okinawa Prefecture.
The aircraft's presence at the U.S. base, situated in a crowded residential district, has drawn the ire of local residents who fear the Osprey's checkered safety history and two recent overseas accidents, one fatal, will lead to accidents.
The Japanese government is seeking to expand MV-22 training missions outside Okinawa in an effort to reduce the amount of base-related activity in the prefecture, whose residents have complained about the bases for decades.
Friday's joint drill was based on a scenario in which a magnitude 9.1 earthquake strikes in the Pacific Ocean off Shikoku, spawning tsunami over 30 meters high.