The Clutha helicopter crash was caused by the pilot's failure to ensure at least one of the fuel transfer pump switches was activated, a fatal accident inquiry has found.

Sheriff Principal Craig Turnbull released his findings from the probe into the disaster which claimed the lives of ten people in November 2013.

The Fatal Accident Inquiry (FAI) found that the crash happened after the helicopter’s engines flamed out sequentially while the helicopter was airborne, as a result of fuel starvation, due to depletion of the contents of the supply tank.

READ MORE: Clutha bar disaster inquiry findings set to be released on Wednesday

He also said David Traill did not follow the correct procedures in dealing with a low fuel warnings in a report published on Wednesday.

Three crew members and seven patrons were killed when the police aircraft crashed into the roof of the popualr Glasgow bar.

READ MORE: Inquiry hears from pilot who flew on day of Clutha crash in Glasgow

The inquiry concluded that 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.

In his determination, Sheriff Principal Craig Turnbull said the central issue was why the pilot, Captain David Traill, allowed the supply tanks to deplete to the point that they did when there was more than sufficient usable fuel available to him in the main tank to allow the helicopter to return to its base.

The report found that both the 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 not switched back on.

The Sheriff Principal’s determination found that there was enough time between the first and second engine flame-outs for Captain Traill to have switched on the fuel transfer pumps.

More to follow.