Cley helicopter crash: What are the likely causes?
06:00 09 January 2014
No stone will be left unturned by those endeavouring to establish what caused the US Pave Hawk helicopter to crash on a saltmarsh in north Norfolk.
The nature of the training mission, weather conditions, mechanical faults, the airframe and even pilot error will be factored in as possible causes before a conclusion is reached.
As the Pave Hawk was taking part in a low level training mission, the height at which the helicopter was operating at will form a critical element of that.
Independent aviation analyst Chris Yates said: “Another key focus will be over whether there had been a mechanical failure which may have played some part in the investigation but it is unusual for military aircraft such as this to come down in such a catastrophic way because military helicopters are among the best maintained in the world.”
Investigators may extend the mechanical failure line of inquiry and look back through maintenance records to establish whether there had been any reports of faults or concerns that may have not been deemed an issue at the time but now, in the context of the crash, have taken on a new relevance.
From thereon, investigators will be looking for other possible causes and working through a checklist; focussing on the mission and the circumstances surrounding it, looking at the weather conditions and the state of the helicopter’s airframe as they seek to build a comprehensive picture of what may have happened and what could have caused the USAF Pave Hawk HH60 helicopter from RAF Lakenheath to crash on Tuesday evening.
“It is about building up the entire picture from it taking off to it crashing and that can take an awfully long time to accomplish,” said Mr Yates.
There are other factors too; some witnesses spoke of hearing the helicopter approach and being concerned about the noise from the engine as though it was in trouble, and as the HH60 was over a nature reserve renowned for its birdlife, a bird strike will have to be considered.
“Those involved in carrying out the investigation have vast experience in crashes such as this and the likelihood is that they will ultimately come up with an answer,” said Mr Yates.
He pointed out it was rare for accidents such as this to happen and added: “We have to be mindful that these are military flyers and they are the best, of the best, of the best.
“It would be unusual, once we get through this investigation, to find that this was pilot error; it might be more mechanical fault.”