No cause determined in Colin McRae crash

[Nigel C]

From www.autosport.com
http://www.autosport.com/news/report.php/id/73235

No cause determined in McRae crash
By Matt Beer Thursday, February 12th 2009, 10:20 GMT


Air accident investigators have been unable to determine a definite cause of the helicopter crash that killed 1995 World Rally champion Colin McRae and three others.

But the official report into the tragedy did criticise risks taken by McRae during the flight, and revealed that he did not have a valid flying licence at the time.

McRae, his five-year-old son Johnny, and family friends Graeme Duncan and six-year-old Ben Porcelli were all killed instantly when McRae's helicopter crashed in woodland on his Jerviswood estate in September 2007.

The Air Accidents Investigation Branch report said McRae's flying licence had expired in February 2005, and that his 'valid type rating' covering his Eurocopter Squirrel helicopter had expired in March 2007.

Footage of the flight shot on Duncan's camcorder was recovered from the scene and used in the AAIB investigation.

Although the report was unable to determine an exact cause of the accident, the investigators felt McRae had taken unnecessary risks during the flight.

"The helicopter probably reached 130-135 knots (150-155mph) as it descended into the valley and its groundspeed would have been about 150 knots (172.8mph) due to the tailwind," said the report.

"In attempting to fly in the valley at relatively low height and high speed, the pilot was undertaking a demanding manoeuvre.

"A high-speed, low-level turning manoeuvre in the heavily wooded valley was a demanding one, which would have subjected the helicopter and its occupants to an increased risk.

"Descending at relatively high speed, and with a strong tailwind, accurate judgement of the turn would have been very difficult. The pilot placed his helicopter in a situation where there was a greatly reduced margin for error, or opportunity to deal with an unexpected event.

"A sudden harsh manoeuvre could have had other implications which, singularly or in combination with the above, could have contributed to the accident.

"Good airmanship dictates that a pilot knows his aircraft's limitations and does not place it in a situation in which they are, or could be, exceeded."

The report also suggested that a possible bird strike, a phenomenon known as 'servo transparency' that can give the impression that the controls are jammed, or accidental interference with the controls by front seat passenger Duncan could have caused the accident.