A report into the disastrous Chinook crash on the Mull of Kintyre in 1994 has highlighted once again the alarming questions around helicopter software in use at the time.

Unexpected engine shutdowns and blowouts from overheating were resulting from problems with new fuel control software introduced as the Royal Air Force's Chinook fleet was upgraded from Mk1 to Mk2.

The report, released by its author Lord Philip on Wednesday, finally removed a gross negligence verdict and exonerated the pilots for the crash, which killed 25 of the UK's most senior intelligence experts and four Special Forces crew.

Lord Philips did not apportion blame for the crash on technology or any other factor. Nevertheless, the report reignites a host of technical concerns raised over the last 16 years, particularly around the new FADEC fuel control software that was introduced to the RAF with the Chinook Mk 2 helicopters.

Click here to read about the serious software questions raised, including the comments by MoD appointed investigators that there was a risk of serious "distraction" to the pilots if a problem occurred with the IT systems.