A total of 29 service personnel died on 2 June 1994 when RAF Chinook ZD576 crashed on the Mull of Kintyre en route from Northern Ireland to Scotland.

The Chinook Justice Campaign is calling for a judge-led public inquiry into the crash, which they allege was caused by the RAF’s use of an unairworthy helicopter.

Representatives yesterday travelled to London for a meeting in Westminster with the UK government’s victims minister, Alex Davies-Jones.

The meeting coincided with a formal complaint by the campaign group to the Ministry of Defence (MoD) over its insistence that there is sufficient evidence to conclude the crash was an accident and its failure to respond to a dossier of evidence submitted by campaigners in December.

In a letter sent yesterday, the group set out four formal demands, including an immediate end to what the families describe as misleading statements, a full response to their evidence, and clarity on whether a judge-led public inquiry will now be established.

The campaign also yesterday welcomed backing for a public inquiry from the Hillsborough Law Now campaign, which says the proposed – but long delayed – duty of candour law must be applied to the Chinook case.

Solicitor Elkan Abrahamson, director of the Hillsborough Law Now campaign, said: “The purpose of the Hillsborough law is to ensure that public bodies are open, honest and transparent with the public and with victims.

“The concerns raised by the Chinook families go to the heart of why that law is needed. The duty of candour should apply in this case, and it should apply now.”

The Chinook families, and a cross-party group of MPs led by Sorcha Eastwood, say the law, which is designed to prevent state cover-ups and ensure transparency from public bodies, should apply swiftly to the Chinook disaster.

Sorcha Eastwood, MP for Lagan Valley, said: “Two years on from this government’s promise to deliver the Hillsborough law, families across the UK are still waiting. With another anniversary of the disaster looming, every day of delay is a broken promise.

“The Chinook case must be among the first this legislation confronts – the evidence is overwhelming and beyond dispute.

“Since January alone, two members of our campaign group have passed away still seeking justice. The Hillsborough bill must be passed urgently, and a full inquiry into Chinook must follow. These families have waited long enough.”

Chris Cook, whose brother Rick was killed and was posthumously, wrongly, blamed for the crash along with co-pilot Jonathan Tapper, said: “The lies and cover-up are happening daily, and the MoD continues to make misleading, false and disingenuous statements about the crash to cover its own mistakes.

“Today we have taken our calls for a full public inquiry under the Hillsborough Law directly to the victims minister, alongside a formal complaint about the Ministry of Defence’s continued failure to engage properly with the evidence.

“If the Hillsborough law is about candour from the state, then the Chinook campaign should be the one of the first cases to test that candour.”