IT was 4.25am on March 22, 2003 when two Royal Navy Sea King Mk 7 helicopters prepared to make a routine handover as they patrolled the Gulf off the al-Faw peninsula in southern Iraq.

Weather conditions were good and both pilots had thousands of hours of flying experience. Yet 30 seconds later the two aircraft collided, erupting into flames before the debris fell into the sea. All seven men on board — six Royal Navy lieutenants and one US serviceman — were killed.

The cause of the collision has remained a mystery. In January 2007 the coroner recorded verdicts of accidental death.

For the families the lack of answers has been agonising. Ann Lawrence, whose son Marc was an observer on one of the crews, said: “The suggestion at the inquest was that two experienced crews had seen each other, then flown into each other. They seemed to be implying that they were responsible for their own deaths.”

Now a former senior civil servant has come forward to reveal one of the main reasons for the crash: Ministry of Defence (MoD) cutbacks.

Safety considerations were ignored because of the pressure that fixing problems would put on restricted budgets, he said.

Both helicopters had their anti-collision lights replaced by strobe lights that interfered with the pilots’ vision. As a result they were turned off at the time of the collision, leaving the two pilots unable to see each other.

According to the official, the MoD and ministers repeatedly ignored his warnings that the lighting was not fit for purpose prior to the incident.

The official, one of the key witnesses in the Nimrod review that last week heavily criticised the MoD’s safety culture, warned against the installation of the strobe lights in 2000. The MoD’s airworthiness team asked him to sign off the lights as safe because they had been fitted to previous versions of the Sea King. He refused and ordered the suspension of plans to remove the existing anti-collision lights.

He said: “The airworthiness regulations hadn’t been followed, the modification had not been appraised by Westland [the manufacturer] and the design faults had not been corrected; nor, crucially, could they provide evidence of trials — so I refused to allow the lights to be fitted.”

Later that year the official went to hospital for heart surgery. In his absence, his superiors overruled him. “When I returned to work, in January 2001, the first thing Westland told me was I’d been overruled and the crap high-intensity strobe light design had been installed. I complained bitterly to my boss.”

In letters passed to ministers by his MP, the official warned repeatedly that the MoD was ignoring airworthiness regulations because of budgetary constraints. He described how he argued that the use of the strobe lights should be suspended until they had been thoroughly tested.

He said: “Not only was I ignored, an instruction was issued to stop work which would have resulted in Westland authorising a corrected design. Given the crash was in March 2003, there was no time whatsoever in the programme to correct these problems.”

Pilots soon found it was impossible to see with the lights on if they were flying low over water or in mist or driving rain, so they switched them off.

The board of inquiry into the loss of the two Sea Kings blamed factors including the inability of pilots to see each other because of the lack of anti-collision lights. It found the strobe lights “not fit for purpose” and ordered their immediate removal from other Sea Kings.

The official said that key documents relating to the lack of airworthiness of the Sea King Mk 7s was “selectively culled” and kept back from the board of inquiry and the inquest.

The families of those killed in the incident are now demanding a public apology from the MoD. Lawrence said: “It was cost-cutting, pure and simple. The MoD is sending boys out to war with aircraft that both they and ministers know are unfit to fly. This ultimately cost my son his life.

“This has been a whitewash all along ... I go through my days from sadness to tears. It does not get any easier.

“I want the truth and I want the Ministry of Defence to admit it was at fault.”

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