THE Clutha tragedy that claimed the lives of two East Renfrewshire men took place after a helicopter pilot "consciously took a risk" and ignored low fuel warnings, an inquiry has found.

Colin Gibson, 33, from Neilston, and 43-year-old Tony Collins, from Clarkston, were among 10 people who died when the Police Scotland aircraft ploughed into the roof of the Clutha bar, in Glasgow, on November 29, 2013.

David Traill, from Lochwinnoch, was piloting the chopper at the time and was among three crew members who lost their lives.

A Fatal Accident Inquiry (FAI) into the tragedy concluded this week that the crash happened after the helicopter's engines flamed out sequentially while it was airborne, as a result of fuel starvation due to depletion of the contents of the supply tank.

The accident was caused by Captain Traill's failure to ensure that at least one of the fuel transfer pump switches was set to on, the inquiry found.

In his determination, Sheriff Principal Craig Turnbull said the accident could have been prevented if the pilot had followed emergency procedures relating to low fuel warnings.

The inquiry heard five low fuel warnings were acknowledged during the G-SPAO helicopter's final flight.

Mr Turnbull said that, by not carrying out the actions set out in the pilot's checklist, Captain Traill "consciously took a risk in proceeding on the basis that the low fuel warnings were in some way erroneous," with fatal consequences.

On the issue of why both fuel transfer pumps were switched off, he said: "Regrettably, when switching off the second (ie the aft) fuel transfer pump, Captain Traill appears to have overlooked the fact that he had previously switched off the forward fuel transfer pump approximately 11 minutes earlier."

The report found both fuel transfer pump switches were in the off position when the low fuel warnings were triggered.

It said that, had one or both of them been switched back on by Captain Traill at that point in time, the helicopter would not have crashed. However, they were left off.

Mr Turnbull said there is no evidence whatsoever to suggest Captain Traill deliberately caused the helicopter to crash and there is evidence to suggest he "made a valiant attempt to land G-SPAO after both engines had flamed out."

He concluded it is "more likely than not that the quantities of fuel displayed on the fuel quantity indication system of G-SPAO contradicted the low fuel warnings, in a manner that persuaded Captain Traill that it was safe to continue flying."

Mr Gibson was among seven customers at the Clutha who died.

Mr Collins, who worked as a policeman, was one of the three crew members on board the helicopter who perished.

A report published by the Air Accidents Investigation Branch (AAIB) in 2015 found two fuel supply switches were off and the pilot did not follow emergency procedures after a fuel warning in the cockpit.

A spokesman for Airbus Helicopters, which manufactured the aircraft, said: "All of us at the company remain deeply saddened by this tragic accident and the heavy loss of life. We would like to express once again our deepest sympathies to the families, friends and colleagues of those who lost their lives.

"Throughout both the AAIB investigation and the subsequent FAI, Airbus Helicopters has fully supported the investigatory and legal processes by providing detailed technical information, in-depth analysis and the presence of our personnel as required.

"We took immediate action to understand the root cause and we have taken note of the findings of both the AAIB and FAI.

"The safety of our fleet remains our number one priority and we are committed to doing everything possible to ensure the safe operation of our helicopters by the thousands of operators whose crews and passengers rely on them every day all around the world."

A Crown Office spokesman said: "This was an exceptionally complex and challenging investigation and the Crown acknowledges that the time taken from the tragedy occurring to convening the inquiry was longer than desirable and that this compounded the distress suffered by bereaved relatives.

"The terms of the Sheriff Principal's determination are presently under consideration."

Police Scotland Assistant Chief Constable Mark Williams added: "We note the Sheriff Principal's determination and are studying its contents.

"The thoughts of everyone at Police Scotland remain with the families and friends of all those, including our three colleagues, who lost their lives in the tragic accident almost six years ago."