THE United States airforce is to reopen its investigation into a crash which claimed the lives of two Suffolk-based fighter pilots.RAF air traffic controller Flight Lieutenant Malcolm Williams was yesterday cleared by a jury of six RAF officers of causing their deaths after a court martial in Helensburgh, Argyll and Bute, Scotland.

THE United States airforce is to reopen its investigation into a crash which claimed the lives of two Suffolk-based fighter pilots.

RAF air traffic controller Flight Lieutenant Malcolm Williams was yesterday cleared by a jury of six RAF officers of causing their deaths after a court martial in Helensburgh, Argyll and Bute, Scotland.

Lieutenant Colonel Kenneth Hyvonen, 40, and Captain Kirk Jones, 27, both based at RAF Lakenheath, were killed on March 26, 2001, after their F-15C fighter jets crashed into the snow-covered mountain Ben Macdui, in the Scottish Cairngorms.

Flt Lt Williams, 47, was charged with causing the death of the two pilots, along with an alternative charge of professional negligence. He denied both charges, and, following a 22-day court martial – the longest and most expensive in RAF history – was acquitted on both counts.

A spokesman for the United States Air Forces in Europe said their own investigation into the accident would reopen in the light of the jury's decision.

The prosecution alleged Flt Lt Williams told the American pilots to fly below 6,500ft after they requested the "minimum vectoring altitude" – a US term unfamiliar to the RAF at the time.

Their fighter jets then crashed into 4,384ft Ben Macdui, the UK's second highest peak during a heavy snowstorm.

Mountain rescue teams found the wreckage of the two planes near the summit and the bodies of Lt Col Hyvonen and Capt Jones were recovered later.

Their deaths sent shockwaves through the close-knit US community at RAF Lakenheath. The last airmen to be killed before the pilots were an F-111 crew who failed to return after a bombing raid in Libya in 1986.

Major Scott Vadnais, of the USAF, said: "Everyone just wishes this tragic accident had not happened. The USAF accident investigation board stood down a year ago at the request of the RAF, but will reconvene now the court martial is over.

"We should be able to conclude our investigation into the accident in the very near future."

Flt Lt Williams said in a statement after the hearing: "Today's verdict is a great relief. The last two years have been extremely stressful for my family and me and we are now looking forward to returning to some sense of normality.

"I am pleased to emerge from this experience completely exonerated and wish to thank the hundreds of people who have sent messages of support from all over the world.

"My sympathy and thoughts go to the families of the two pilots who lost their lives in this tragic accident. Their loss is heartbreaking."

Flt Lt Williams' wife Susan said the two-year ordeal had been a "David and Goliath" struggle.

"No one emerges from the ordeal of a court martial as a winner," she said. "Two fine pilots have lost their lives and our prayers continue to be extended to their wives and families."

Richard Dawson, president of the Guild of Air Traffic Control Officers (Gatco), said outside the court: "The prosecution did not present the evidence that was available. Had that evidence been used by the prosecution from the outset, there is every likelihood that this court martial would never have taken place."

In a statement, Gatco, which partly funded Flt Lt Williams's case, said: "Gatco is pleased to have supported Flt Lt Williams throughout his ordeal and is delighted that his court martial has now ended with him being acquitted of all charges.

The statement continued: "The evidence presented during the last four weeks has highlighted a need to revisit the Royal Air Force/United States Air Force arrangements to ensure that adequate safeguards and common procedures are in place for the conduct of low flying training and air space management in United Kingdom airspace.

"Gatco will continue to work with all air traffic service providers, civil and military, to achieve the highest levels of safety."

Flt Lt Williams will be fully reimbursed for his legal fees. It is believed he has already spent around £15,000 defending his case.

An RAF spokesman said: "A long and complex case was dealt with great care by the board, and the fact that they have given the benefit of the doubt to the accused and found him not guilty is a sign of a good, strong system of justice."

Flt Lt Williams, of RAF Leuchars, Fife, Scotland, is believed to have been the first UK military controller in living memory to be court martialled in connection with a fatal air crash.