The helicopter that crashed in Uttarkhand’s Uttarkashi district on May 8 struck an overhead fibre cable with its main rotor blade while attempting to land, the Aircraft Accident Investigation Bureau said on Saturday, The New Indian Express reported.

In its preliminary report, the division of the Ministry of Civil Aviation that investigates such accidents said that the “aircraft failed to land and subsequently tumbled down the hillside, eventually coming to rest against a tree roughly 250 feet into a gorge”.

Six persons, including the pilot, were killed and one injured after the helicopter crashed near Gangnani in Uttarkashi on May 8. The helicopter, belonging to AeroTrans Services Private Limited, had taken off from a helipad in Dehradun and was heading to the Gangotri Dham of the Char Dham Yatra circuit.

The circuit is a Hindu pilgrimage to the four shrines of Kedarnath, Badrinath, Gangotri and Yamunotri, all of which are in Uttarakhand.

The Aircraft Accident Investigation Bureau, in its report, said that the helicopter lifted off from the Kharsali airpad at 8.11 am and the accident happened at 8.35 am in Gangnani, PTI reported. The helicopter was destroyed in the crash, but there was no fire, it added.

The helicopter flew for 20 minutes before descending from its assigned altitude, the report said.

“Initially, the pilot attempted to land on the Uttarkashi-Gangotri Road (NH 34) near Gangnani in Uttarkashi,” the news agency quoted the report as saying. “During the landing attempt, the helicopter’s main rotor blade struck an overhead fibre cable running parallel to the road.”

The report said that this caused the aircraft to lose control and plunge into a gorge.

The helicopter, which was powered by an engine built by Rolls Royce, was manufactured in 2008.

The Aircraft Accident Investigation Bureau also said the United States’ National Transportation Safety Board and Canada’s Transportation Safety Board have appointed official representatives and technical advisors to assist with the investigation.

“The investigation team is working closely with them to decide the next steps needed to find the exact cause of the crash,” the report said. “Records obtained from various stakeholders are currently being scrutinised.”

The report comes amid mounting safety concerns about such helicopter accidents in the state.

On June 15, seven persons died in Rudraprayag district after a helicopter carrying pilgrims taking part in the Char Dham Yatra crashed near the Gaurikund area.

This was the fifth helicopter accident in Uttarakhand in about 40 days.

In the wake of the accidents, Chief Minister Pushkar Singh Dhami has formed a high-level committee chaired by Home Secretary Shailesh Bagauli to draft a standard operating procedure for helicopter services in the state.

The committee is expected to submit its recommendations by August 15.

Also read: Why helicopters to Kedarnath are crashing