Unforecast severe weather contributed to a Super Puma helicopter landing with less than reserve fuel at Barrow Island in February, an ATSB investigation has found.
The crew was returning to Barrow Island, WA, after conducting night deck-landing practise on an offshore vessel when they encountered severe turbulence and lightning. The crew were forced to divert away from their destination for 10 minutes, which made fuel critical.
Eventually, the helicopter was able to land at Barrow Island by tracking below the lowest safe altitude and with one engine shut down to conserve fuel. Only 170 litres was left in the tank, which was below the fixed reserve.
According to the ATSB report, "the crew departed Barrow Island for the night training flight with sufficient fuel to return and land with standard reserves intact as allowed by the aerodrome forecast, but encountered unforecast severe weather on the return sector that prevented a routine visual or instrument approach.
"The validity of the Barrow Island aerodrome forecast had been extended to cover the duration of the flight, but the forecast did not include any reference to severe weather, and was not amended when the adverse trend became evident because the forecaster on duty at the time was unaware of the extended validity."
The report hinted at a breakdown in communications at the Bureau of Metrology during a change in shifts that led to the forecaster coming on duty not knowing the Barrow Island TAF had been extended, and therefore did not issue an amendment to include the storms.
Although it made not have made a difference, the ATSB report mentions that the crew did not have to submit a flight plan, which meant they weren't passed weather updates during the flight.
The ATSB also found that the helicopter crew managed the risks to ensure a safe arrival with 20 minutes of single-engine fuel remaining on board.
The full report is available on the ATSB website.