Helicopter tragedy ‘caused by engine failure’

But the helicopter, which was assisting police operations on the night of November 29, 2013, had 76kg (168lb) of fuel in its main fuel tank and there was no evidence of blockages or leakages, said the special bulletin from the Air Accidents Investigation Branch (AAIB).

The report said both engines had “flamed out” before the EC135 helicopter crashed into The Clutha Vaults bar at 10.22pm, killing the pilot and two Pcs on board as well seven people in the pub.

Examination of the engines showed “no evidence of foreign object damage or intake or exhaust blockage in either engine”.

Also, the report said no faults were found with the transmission or rotor system, there was no evidence of structural failure or in-flight fire and no evidence of damage caused by bird strike or a foreign object hitting the aircraft in flight.

No CCTV recordings had been obtained which captured the end of the flight and the recorded radio transmissions did not contain any reference by the crew to difficulties with the aircraft.

Due to publish a full report at a later date, the AAIB said today its continuing investigation “will seek to determine why a situation arose that led to both the helicopter’s engines flaming out when 76kg remained in the fuel tank group”.

The AAIB said it also wanted to find out “why no emergency radio transmission was received from the pilot, and why, following the double engine failure, an autorotative descent and flare recovery (a controlled landing) was not achieved”.

The report also revealed that three weeks after the crash, the helicopter’s operator Bond Air Services had, on December 20 2013, amended its operations manual about fuel reserves while flying.

The pilot who died was David Traill and his passengers were Pc Kirsty Nelis and Pc Tony Collins.

More than 100 people were in the popular city centre bar, near the River Clyde, at the time of the crash.

A book of condolence signed by MPs after the crash has been handed to the city by Commons Speaker John Bercow.

Mr Bercow presented Glasgow’s Lord Provost Sadie Docherty with the book at the City Chambers in London.

The book had been placed in the House of Commons for MPs, peers and staff to sign in the aftermath of the tragedy.

Mr Bercow said: “I think the terrible tragedy of what happened at the Clutha struck home as far as large numbers of my parliamentary colleagues were concerned.”