Two MV-22 Osprey aircraft made emergency landings at Ishigaki airport in southern Japan today, the administrative office of Ishigaki city told Mainichi Japan.
The U.S. military tilt-rotor planes landed at around 5 p.m., early Friday morning. Okinawa Gov. Takeshi Onaga, speaking to reporters, criticized the latest incident as "truly outrageous".
Prior to this incident, the aircraft made an emergency landing on a U.S. auxiliary airfield on Ie Island, Okinawa Prefecture, in June. Moreover, the same aircraft was spotted emitting white smoke while it was parked at the U.S. military's Iwakuni base in Yamaguchi Prefecture on Aug. 28.
Ospreys, which takes off and land like helicopters but cruise like planes, have stirred safety concerns in Japan due to a record of accidents overseas, including fatal ones, since the first deployment in 2012.
Japan's Ground Self-Defense Force is planning to acquire 17 Ospreys to be deployed at Saga airport in southwestern Japan.
The Osprey involved in these problems belongs to the U.S. Marine Corps Air Station Futenma in Ginowan, Okinawa Prefecture.