The son of a man killed in the RAF’s worst peacetime air crash has raised an official complaint over the decision by the Ministry of Defence (MoD) to lock away files relating to the tragedy for 100 years.

Niven Phoenix, whose father Ian was a detective superintendent for the Royal Ulster Constabulary, has also demanded the MoD apologises for statements relating to investigations into the incident.

Twenty-nine people were killed when the RAF helicopter crashed on the Mull of Kintyre on June 2, 1994.

Two pilots were initially accused of gross negligence over the crash but a review of the incident in 2011 found they should not have been blamed.

Mr Phoenix has now written to Defence Secretary Grant Shapps to raise concerns about recent statements made by the MoD in response to complaints from some families of the deceased over past investigations into the tragedy.

Responding to remarks made by Mr Phoenix’s mother Susan relating to her belief the real cause of the crash has yet to be determined, the MoD issued a statement last week saying no safety issues with the Chinook helicopter were raised in a report published in 2011 following an independent review.

Mr Phoenix has requested the MoD retract and apologise for making that statement after pointing to a section of the report saying a decision was taken at a military site to stop flying the same model of helicopter because of “malfunctions” shortly before the 1994 crash.

His letter to Mr Shapps, seen by the PA news agency, said: “We respectfully request you retract and apologise for the disingenuous media commentary that has recently been made ahead of the 30th anniversary of the crash.

“We would also like to make an official complaint of your sealing the files on this crash until 2094. That is a continuation of the dissembling around this crash and incongruent with your latest false commentary on the safety record of the MKII Chinook.

“We have asked our respective MPs to address this, and we request the MoD be made answerable to Parliament as to the reason.

“Given the latest fallout from the Post Office and NHS scandals, we respectfully submit that your current behaviour is out of step with the times and unacceptable given the clearing of the pilots’ names. You seem intent on peddling a false and offensive narrative to the victims of this disaster in the hope we will simply die off or go away.”

The letter continues: “We would ask that the MoD retract these untrue statements for all the families still in limbo from this unresolved accident.

“We find it particularly distasteful that the MoD should be trying to spin the same disingenuous narrative on the eve of an anniversary that, much like the truth, you have chosen to wholly ignore.”

The independent review, announced in 2010 and published in 2011, found criticism of the Board of Inquiry on the grounds that insufficient attention was paid to airworthiness and maintenance aspects was unjustified.

Asked for comment, a MoD spokesperson reiterated the department’s earlier comments: “The Mull of Kintyre was a tragic accident and our thoughts and sympathies remain with the families, friends and colleagues of all those who died.

“In 2010 the Mull of Kintyre independent review was carried out and the findings were fully accepted.

“The review did not find new evidence to suggest mechanical failure, and no safety issues with the Chinook mark 2 were raised in the report.”