A HELICOPTER pilot was one second away from preventing a North Sea

disaster, it was revealed yesterday.

Air accident investigator Ann Evans said Captain Jonathan Shelbourne

appeared to have done everything he could to avoid the tragedy last

March, but tests showed that complex weather conditions that night

prevented him from saving the aircraft.

Miss Evans told the fatal accident inquiry in Aberdeen that the last

moments of the flight were analysed by computer, based on information

from the helicopter's flight data recorder.

They revealed that Captain Shelbourne had recognised the helicopter

was plunging towards the sea.

He was only one second too late in taking corrective action, she said.

Eleven men died when the Bristow's Super Puma helicopter crashed

seconds after taking off from Shell's Cormorant Alpha platform.

The aircraft was on a routine two-minute flight to the accommodation

barge Safe Supporter.

The inquiry has heard that a blizzard was blowing that night, and the

temperatures in the North Sea were the coldest for six years.

It is the first time that information from a flight data recorder has

been available to investigators after a helicopter accident in the UK.

Miss Evans, of the Government's Air Accident Investigation Branch at

Farnborough, Hampshire, said two computer simulations were carried out.

One was by the manufacturers, Eurocopter France, and the other at

Farnborough by the Government's Defence Research Agency.

Both tests showed that Captain Shelbourne had operated the aircraft's

throttle when he realised the aircraft was descending rapidly.

The Eurocopter test revealed that his actions should have resulted in

the aircraft flying to safety.

But the Farnborough simulation, which built in the complicated weather

conditions known as a vortex ring, showed Captain Shelbourne was one

second too late in applying throttle.

Mr Hugh Campbell, QC, representing the pilot, asked Miss Evans: ''He

noticed something was going wrong and took steps to correct it. Had he

taken that action a second beforehand he would have been able to fly

away?'' Miss Evans replied: ''Yes.''

Mr Richard Whidborne, principal inspector with the AAIB, said the

hours before the crash had constituted a ''long day'' for Captain

Shelbourne.

He had been called from home while on a weekend off, had to fly from

Aberdeen to Shetland, where there had been delays in loading freight and

clearing snow from the aircraft, and he had been asked to carry out more

flights as the day went on.

Mr Whidborne said fatigue may have increased as the day wore on. ''I

think a pattern of increased aggravation built up,'' he said.

He agreed that mistakes were more likely to be made when people are

fatigued.

In this case he felt action had been taken to get out of a ''hazardous

situation'', but said the degree of urgency was open to question.

He added that after the crash, Captain Shelbourne had told him he

could not understand why the helicopter had not flown away safely after

he had taken the actions he had.

This made Mr Whidborne wonder if there was an ''extra ingredient''

which had made the crash unavoidable.

He said that co-pilot Ian Hooker, who died in the accident, had called

''watch the height'' five times to Captain Shelbourne.

The inquiry resumes on Monday.