What happened
On May 3, 2005, an Agusta A109K2 helicopter, registration JA11PC, operated by the Shizuoka Prefectural Police, crashed into a residential neighborhood in Shimizu-ku, Shizuoka City. The aircraft was conducting a road traffic congestion survey when the accident occurred at approximately 16:28 JST.
The flight originally intended to use a different aircraft, but due to a malfunction in the primary helicopter, the crew switched to JA11PC. During the mission, the flight path was extended to include a survey of the Tomei Expressway, which altered the original flight plan. Witnesses near the crash site reported seeing the helicopter flying at an unusually low altitude, significantly lower than typical operations. As the aircraft approached the Kusanagi River area, observers noted the engine sound went silent and the main rotor speed decreased. The helicopter then pitched forward and struck the ground, triggering a post-crash fire. All five persons on board, including the pilot in command and four officers, were fatally injured.
The investigation
The investigation examined the wreckage, engine components, and transmission systems, with technical assistance from authorities in Italy and France. Investigators analyzed flight logs, radio communications, and digital photographs taken during the mission. The inquiry also included a flight simulation to reconstruct the aircraft's final moments. The investigation focused on the aircraft's fuel state, the sudden loss of engine power, and the failure of the crew to establish an autorotation.