What happened
On February 19, 2012, at approximately 13:25 JST, a Eurocopter EC120B, registration JA710H, operated by HELI-SYS japan, inc., experienced a dynamic rollover while attempting to depart from the Karifuridake temporary helipad in Minami-Furano Town, Hokkaido. The aircraft was performing heli-skiing operations, transporting skiers and guides to the mountain summit.
During the takeoff sequence, the pilot noted an unusual sensation involving the uneven behavior of the landing skids. After an initial attempt to clear a perceived restraint resulted in a slight forward movement, the pilot resumed the liftoff. This second attempt caused the helicopter to abruptly roll to the right. The aircraft sustained substantial damage, including a fractured tail boom, broken main rotor blades, and a damaged cockpit windshield, though no fire broke out and the pilot escaped without injury.
The investigation
The Japan Transport Safety Board (JTSB) conducted an investigation involving on-site inspections and interviews with the pilot, the ground escort, and witnesses. Investigators examined the condition of the Karifuri Helipad, which was covered in hardened snow. The investigation focused on the physical state of the landing area and the sequence of pilot inputs.
Evidence at the site included broken branches of creeping pine, which had been hidden beneath the snow surface. The investigation also reviewed the company's training records, noting that specific training and evaluation procedures for heli-skiing and cold-weather mountain operations were not sufficiently established in the pilot's training curriculum.