What happened
On July 26, 2014, at approximately 14:45 JST, a privately owned Robinson R44II helicopter, registration JA44AT, was attempting to land at the Thalassa temporary helipad in Toba City, Mie Prefecture. The aircraft was carrying the captain and one passenger. Due to a southerly wind, the pilot approached the site from the north.
Upon arrival, the pilot observed several vehicles parked near the designated takeoff and landing area. Following instructions from the landowner on the ground to avoid these vehicles, the pilot maintained a hover over the south side of the helipad. While attempting to turn the aircraft toward the north to prepare for a subsequent departure, the tail cone of the helicopter struck trees located to the east. The impact caused the tail cone to break and fall away from the fuselage, and several tree branches were broken in the process. The aircraft landed with a wobble, resulting in substantial damage to the lower fuselage frame, the tail cone, and partial fractures to the main rotor blades. There were no injuries to the occupants.
The investigation
The Japan Transport Safety Board (JTSB) examined the flight history, the physical damage to the Robinson R44II, and statements from both the pilot and the landowner. The investigation focused on the flight path relative to the approved landing procedures and the spatial relationship between the aircraft and the surrounding obstacles. The investigators also reviewed the specific conditions of the landing permit, which required a landing direction of 325° and a takeoff direction of 010°, as well as the requirement for ground security to keep the landing area clear.
Findings
- The investigation established that the tail cone made contact with trees on the eastern side of the aircraft during the turn.
- Although the pilot believed he had checked the clearance, the physical evidence indicates he failed to accurately judge the distance between the aircraft and the trees.
- The aircraft did not follow the approved flight application; the pilot approached from the north rather than the permitted 325° direction.
- The landing area was not kept clear of obstacles as required, as the presence of parked vehicles forced the pilot to hover in an unauthorized location.
- Had the pilot adhered to the approved landing direction and area, the need for the maneuvering turn would have been eliminated, likely preventing the collision with the trees.