Mr Hill was a former aeronautical engineer who played a key role in clearing the two pilots of blame for the 1994 Chinook helicopter crash.

A total of 29 service personnel died when the helicopter crashed on the Mull of Kintyre en route from Northern Ireland to Scotland in what remains the RAF’s worst peacetime accident.

The Chinook Justice Campaign is pursuing a judicial review against the Ministry of Defence (MoD) over its failure to release files on the crash and has called for the establishment of a statutory public inquiry.

In a statement, the campaign said: “Our friend, fellow campaigner and technical advisor David Hill, has died after a very short and difficult battle with cancer.

“Without David, there would be no Chinook Justice Campaign as it exists today. His expertise gave our families confidence, his evidence gave us credibility, and his unwavering commitment sustained the campaign to clear the two pilots of blame, and  bolstered our current campaign for the full truth, and a judge-led public inquiry.

“We will honour his memory by continuing the work to which he devoted the last 31 years of his life.”