THE manufacturer of the RAF’s Nimrod spy planes had warned of “frequent” fires on board the aircraft 18 months before one exploded over Afghanistan last September, killing all 14 men on board.

The BAE Systems report said there had been 880 fires or “smoke-related incidents” on the aircraft over the preceding 20 years, an average of 40 a year.

It also highlighted the large number of fuel leaks on board the aircraft and recommended the fitting of a fire suppression system in the bomb bay.

A series of confidential reports uncovered by The Sunday Times have detailed how the Ministry of Defence (MoD) was aware of a history of potentially dangerous fuel leaks on the Nimrods. But the new report shows the MoD also knew of the dangers of fires that could ignite the fuel.

The BAE Systems report, published in March 2004, was compiled because the MoD wanted to save money by delaying the introduction of an up-dated replacement until 2010. It asked BAE Systems to detail whether it would be safe to do so, given the age of the aircraft, which dated back to the 1960s.

Despite the leaks and the warning that fires on board would be “frequent” in future, the MoD decided “it was not appropriate” to fit a fire suppression system in the bomb bay.

The pilot of the Nimrod that exploded on September 2 last year reported a fire in his bomb bay and tried to land. He dropped 20,000ft in 90 seconds, but at 3,000ft the starboard wing exploded, followed by the rest of the aircraft.

The board of inquiry into the explosion will report next week and is expected to confirm preliminary findings blaming air-to-air refuelling for the leaks.

The MoD said the high number of fire and “smoke-related incidents” reflected the RAF’s comprehensive reporting system. Before the explosion, it said: “There were two fires serious enough to result in the loss of an aircraft. Neither resulted in any fatalities.”

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