Flight History
On Saturday, June 3, 2017, a Cessna 172P, registered JA3989, operated by New Central Airservice Co., Ltd., departed from Toyama Airport for Matsumoto Airport around 14:50 Japan Standard Time. The aircraft crashed near the top of Mount Shishi-dake (elevation approximately 2,700 m) in the Tateyama Mountain Range.
Injuries to Persons
There were four people on board: the pilot in command (PIC), a pilot, and two passengers. All four were fatally injured.
Damage to the Aircraft
The aircraft was destroyed, but there was no outbreak of fire.
Probable Cause
The Japan Transport Safety Board determined that it is probable that as the aircraft entered clouds during VFR flight over the mountainous region, the PIC and the pilot lost the ability to visually confirm the terrain and their position. Consequently, the aircraft approached the mountaintop and crashed. It is somewhat likely that the crash was due to unavoidable loss of visual contact, failure to maintain minimum safe altitude due to icing or a stall, or severe turbulence, but this could not be determined because all occupants were fatally injured. Regarding the entry into clouds, the board found it probable that the PIC and the pilot had not thoroughly confirmed the weather forecast for the mountainous region before departure and delayed the decision to turn back during flight.
Recommendations
The Japan Transport Safety Board recommended that the Minister of Land, Infrastructure, Transport and Tourism take measures to inform pilots about the hazards of icing for aircraft not certified for flight in icing conditions, encourage proper use of seat belts and shoulder harnesses, provide information on ELT installation and operation, and ensure search and rescue aircraft can monitor distress frequencies.