On October 19, 1994, a Mitsubishi MU-2 Marquise (registration 53-3219) operated by Japan Air Self-Defense Force - Kōkū Jieitai was involved in an aviation accident near Hamamatsu, Japan in flight. 4 people were killed. Investigators recorded the probable cause as: The aircraft entered an uncontrollable dive following the onset of technical malfunctions during a test flight. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 8 related events involving the same aircraft type or operator are linked below.
An aircraft crashed into the sea near Hamamatsu during a post-maintenance test flight, resulting in the deaths of all four crew members.
What happened
During a scheduled test flight following recent maintenance work, the aircraft experienced a critical loss of control while in transit. During the flight, the co-pilot contacted air traffic control to report the presence of technical difficulties. Shortly after this communication, the aircraft entered a steep dive. The flight ended when the plane impacted the ocean surface in the waters off Hamamatsu.
Findings
The flight was being conducted as a post-maintenance evaluation.
The crew reported experiencing technical issues prior to the loss of control.
The accident resulted in four fatalities among the crew members.
Probable cause
The aircraft entered an uncontrollable dive following the onset of technical malfunctions during a test flight.