The parents of a six-year old boy killed when the helicopter Colin McRae was piloting crashed have said the tragedy was "completely avoidable."
Ben Porcelli died along with the rally champion, his son Johnny, 5, and Graeme Duncan, 37, when their helicopter came down in woodland near Lanark.
An official accident report said it was not possible to say with any certainty what caused the crash.
Mark and Karen Porcelli said it was clear "unnecessary risks" were taken.
The Air Accident Investigations Branch (AAIB) has just published its long-awaited findings.
The report said Mr McRae was "undertaking a demanding manoeuvre" before the Eurocopter Squirrel aircraft hit trees and crashed on 15 September, 2007, just 150 yards from the landing strip at the McRae family's home in Lanarkshire.
The report did not pinpoint the cause of the crash in which four people died
It also said the former rally world champion's flying licence had expired and he was not authorised to fly that type of aircraft as his "valid type rating" had lapsed in March 2007.
The findings revealed that passenger, Graeme Duncan, had recorded video footage on a camcorder during the helicopter's flight prior to the crash.
This was recovered from the wreckage and viewed by investigators to help them piece together the moments before impact.
The AAIB report said the mood on the helicopter was jovial and the passengers could be heard shouting and laughing, "enjoying the experience".
In a statement the Porcelli family said: "We are relieved that the AAIB report has finally been published, particularly since the circumstances of the accident which took Ben's life were presented to us by the AAIB in February 2008.
"The cause of the crash is clearly outlined in the report.
Colin McRae and his son Johnny, 5, died in the crash
"Most of the flight was captured on video and it is clearly evident that unnecessary risks were taken and that the accident was completely avoidable."
However, a spokesman for the McRae family said the cause of the crash remained a mystery.
Speaking on behalf of the family, Colin's father Jimmy Rae said: "The AAIB report, in line with the findings of our own experts, has been unable to reach any firm conclusions on the accident and it is therefore extremely difficult to come to terms with the fact that we will never know the actual cause of the crash.
"It has been confirmed by the instructors, examiners and fellow pilots with whom he flew, that Colin's skills as a helicopter pilot were of the highest order.
"This has been a very sad and distressing time for us, as it has been for the Porcelli and Duncan families, and we would now like to draw a line under this tragic affair."
The McRae family's solicitor, Mr Peter Watson, said, "We welcome the fact that the AAIB have made several safety recommendations as a consequence of this crash and that operators of this aircraft -the Eurocopter AS350B2 Squirrel - should now be informed by the manufacturer as to certain hazards and recovery actions relating to the operation of the craft."
Mr Watson added, "We acknowledge that the report recognises the fact that, whilst Colin's licence was out of date, this was not a contributory factor in the accident.
"Colin first qualified during the transitional period whilst the British lifetime licence system was being replaced by the European Joint Aviation Requirements five-year licence and this caused considerable confusion.
"We note that the AAIB recognise that the CAA Authorised Examiner who conducted Colin's Licence Proficiency Checks (LPCs) in March 2005 and March 2006 did not check the pilot's licence on either occasion, being under the impression that he had been issued with a lifetime validity licence, as was Colin."
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