The UK National Police Air Service (NPAS) has mandated that all police-operated EC135s fly with more fuel on board and increase minimum operational fuel levels, in the light of an unspecified technical error that has seen Bond Air Services ground its 22-strong fleet of the type.

Chief Superintendent Ian Whitehouse, NPAS chief operating officer, says, however, that it will not restrict EC135 operations unless informed by the UK regulator or the helicopter manufacturer.

"There is currently no notice in place from the [Civil Aviation Authority] or the original equipment manufacturer to ground any aircraft, and so we have not done so. If such a notice is put in place then we would immediately and carefully consider it," says Whitehouse. “In light of the technical issue identified by Bond Air Services, as a precautionary measure we are increasing fuel levels on all NPAS EC135 aircraft and increasing the minimum level of fuel which pilots are allowed to operate on."

All parties have been at pains to distance the Bond grounding from the fatal crash of an EC135T2 in Glasgow on 29 November. Initial findings published by the Air Accidents Investigation Branch earlier this week indicated the engines and gearbox of the crashed helicopter, operated on behalf of Police Scotland by Bond Air Services, were still capable of providing power to the main rotors and fenestron tail rotor.

The aircraft's fuel tanks still contained around 95 litres (25USgal) of fuel, the AAIB also found.

But Whitehouse adds: “The investigation into the Glasgow incident remains ongoing, and it would therefore be inappropriate to comment further on that incident or speculate on any connections.”

The NPAS board was presented with "early information" into the Glasgow crash on 12 December, it says.

“Both the Chief Constable [of West Yorkshire, Mark Gilmore] and Chief Superintendent Ian Whitehouse, the accountable manager of NPAS, have assured the board that all relevant risks have been identified at this stage and all appropriate operational measures have been taken,” the board adds.

Source: FlightGlobal.com