What happened
On June 28, 2013, a Dauphin AS 365 N3 helicopter, registration VT-PHZ, was conducting emergency rescue operations in the Uttarakhand region following severe flash floods. The aircraft, operated by Pawan Hans Ltd., was tasked with evacuating people from the Harsil Army Helipad, located at an altitude of 8,200 feet.
While the crew had successfully completed two previous landings at the site that day under favorable headwind conditions, the third landing attempt encountered significantly different weather. During the approach, the helicopter was subjected to strong, gusty tailwinds reaching 30 knots. As the aircraft reached short finals, the pilot was unable to manage a high rate of descent. Despite applying maximum collective power to arrest the descent, the aircraft lacked sufficient power margin due to the high landing weight and high altitude. This led the helicopter into a vortex ring state, causing it to become uncontrollable and strike the ground at approximately 50 feet. The impact caused substantial damage to the tail boom and aft structure, though all zero fatalities were reported as the occupants escaped without injury.
The investigation
An inquiry commissioned by the Ministry of Civil Aviation examined the flight history, aircraft maintenance, and crew qualifications. Investigators reviewed the flight data, which confirmed the presence of heavy tailwinds during the final approach. The investigation also scrutinized the operational readiness of the crew, noting that while the pilots were experienced, they lacked recent experience in mountainous terrain.
Technical inspections of VT-PHZ revealed significant structural failure, including a ruptured tail boom, broken hydraulic lines, and damage to the fenestron and horizontal stabilizer. The investigation also looked into the company's deployment processes and the crew's adherence to standard operating procedures, including the use of mandatory altitude-specific flight modes and Crew Resource Management (CRM) practices.