DEFENCE secretary Gavin Williamson has been urged to save key files on the Chinook helicopter disaster.

Earlier this week, the Ministry of Defence told Northern Ireland’s News Letter that all documents relating to the crash, in which 29 people died, would be reviewed for “disposal or disclosure” under the 30-year rule.

But in a letter to the minister, SNP MP Brendan O'Hara has said he "cannot fathom what benefit there would be in destroying such an important, if terrible part of our military history."

The RAF Chinook helicopter crashed over Mull of Kintrye in June 1994 while flying between Aldergrove, near Belfast, to Inverness.

On board the helicopter were 25 of the most senior members of Northern Ireland’s counter terrorism intelligence community.

An RAF board of inquiry initially blamed the pilots, Flight Lieutenants Jonathan Tapper and Richard Cook, saying they were “negligent” and had used the wrong rate of climb over the Mull.

But in 2011 the men were completely cleared by a review commissioned by the then Defence Secretary Liam Fox.

Now there’s some suspicion the MoD is trying to cover up their own “deceit and subterfuge”.

Dr Susan Phoenix, whose husband RUC Det Supt Ian Phoenix was killed in the crash, and who co-wrote a book on the affair, Phoenix, Policing The Shadows, said she still feels that senior RAF and MoD officers “were not brought to account” for their role in the matter.

“To quote then defence secretary Sir Malcolm Rifkind after the last review, he said with foresight: ‘There remain unresolved matters. It is right that these issues should continue to be pressed’.”

She added: “In summary, what we appear to have here, in spite of the renewed good reputations for our Mull of Kintyre Chinook pilots, is a litany of deceit and subterfuge.”

Peter Watson, the lawyer for Cook’s family, said: “It is in the public interest for papers such as these to be available for inspection and review, and that will restore public confidence in those who make decisions.

"If there have been mistakes, honest and frank acceptance of errors is a better course.”

O'Hara said the MoD should not even be considering disposing of the records.

“It is unthinkable that the only direct record we may have left from the tragedy in 1994 could be disposed of without truly understanding why this accident happened.

“This was a major incident for those affected, their families and their loved ones but it was also a major incident for the Mull of Kintyre.

“Whilst this tragedy remains in living memory, disposing of these records is inconceivable”.

The MoD has confirmed that many files are due for review this year.

A spokesperson said: “Records that were closed in 1995 and 1996 will be reviewed for release or alternative disposal this year. These reviews have not been completed, and a decision will be made in due course.”