The wife of a man who was killed 30 years ago to the day in an RAF helicopter crash has said prosecutors must investigate the disaster.

Susan Phoenix’s husband, detective inspector Ian Phoenix was killed in the 2 June 1994 Chinook helicopter crash, where the RAF aircraft crashed on the Mull of Kintyre in foggy weather.

All 25 passengers and all four crew members aboard the RAF Chinook ZD576 were killed.

Among the passengers were several Northern Ireland intelligence experts.

It is considered one of the RAF’s worst disasters.

Ms Phoenix has since written to the Lord Advocate Dorothy Bain, accusing the Ministry of Defence (MoD) of a “cover up” and “unacceptable behaviour”.

In the letter, which was also sent to the Scottish Government, Ms Phoenix wrote: “I feel the Scottish Authorities are best placed to help with what I can only describe as the MoD’s unacceptable behaviour over the years, both towards the bereaved families and the deceased pilots.

“This falls woefully short of acceptable standards, as does that of legal authorities, who have not seen fit to order any investigation into the deaths despite evidence of illegal acts having emerged over a period of years.

“All of this information has been publicised and placed in the public domain most recently by a BBC documentary exposing a cover up akin to what we have seen in The Post Office situation and the NHS Blood Scandal.

“The current situation means families remain in limbo and legally the MOD seem untouchable.”

She claimed Lord Alexander Philip had agreed the helicopter was “not airworthy, despite this being ‘mandated’ upon the RAF”, and that the crew were not informed of this at the time, and claimed that this information was withheld from a Fatal Accident Inquiry (FAI) that followed.

She said: “Had he been told this, my husband, and no doubt his colleagues, would have asked why no alternative transport was being arranged. He was sent to his death by a conscious decision to ignore legal obligations.

“Following the latest media reports summarising the evidence concealed from the Fatal Accident Inquiry, could you please explain why no investigation has been ordered?

“The Crown Office has been in possession of the fresh evidence, withheld from all Inquiries, for some years.”

She claimed MoD witnesses “serially misled” a sheriff during the FAI and later the House of Lords’ select committee on the disaster.

She wrote: “This is a serious matter which has served to extend the heartache for all 29 families”.

She added: “I have tried not to dwell on the loss of my husband and his colleagues, who were also my friends, as I sought to rebuild a life for myself and family.

“However, now in my mid seventies, I feel entitled to know what happened?

“MoD was content to blame the pilots for 17 years, and legal authorities had a valid reason not to act as the ‘guilty’ were deceased.

“But now they have been cleared one must ask why has the case not been re-opened?”

She called upon the Crown Office to make an official statement as the tragedy marks 30 years, and claimed that if the FAI was not misled, further action could have “prevented subsequent loss of life in the subsequent tragedies that plagued the RAF”.

She wrote: “The continual obscure and dishonest replies to my requests for FOIs (Freedom of Information) to the Minister of State for the Armed Forces, over the years, are glaring in their dedication to close down further questions.

“I will be on the Mull of Kintyre with my ex RAF pilot son on the anniversary this year at the very kind and considerate invitation of the local church and Royal British Legion.

“The people of the Mull have always supported us as a family and also deserve a proper explanation for the disaster that devastated their beautiful Island for a very long time.

“I believe that the time is long overdue for justice to be done in this case and that it is within your remit and Scottish justice, to ensure that this can happen to help right a grievous wrong”.

A spokesperson for the MoD said: “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”.

A spokesperson for the Crown Office and Procurator Fiscal Service said: “We respect and value correspondence from bereaved families and will address the concerns raised by Dr Susan Phoenix in a reply to her letter”.

The Scottish Government declined to comment.