Bond engineers were “cautious about what they were doing” in the days leading up to the 2009 North Sea Super Puma disaster.
The fatal accident inquiry into the deaths of the 16 people killed in the crash heard in the run-up to the tragedy an earlier accident was still under investigation.
John Crowther, engineering manager for Bond, said the company was under the spotlight after the initial incident but it had a “positive effect” on maintenance operations.
He added: “It would be too strong to say ‘overly cautious’, but we were being cautious.”
Mr Crowther, 55, told the inquiry at Aberdeen’s Town House that Bond’s team was under close scrutiny around the time a metal fragment was found in the gearbox of the Super Puma which plunged into the North Sea a week later, killing all 16 people on board.
The fatalities on April 1 happened six weeks after 18 people were plucked from the sea following another Super Puma crash.
In the earlier incident, a Bond-operated EC225 helicopter carrying offshore workers to a BP platform went down about 125 miles east of Aberdeen. A huge sea and air rescue operation was launched and everyone survived. The incident was put down to pilot error and a faulty alert system.
But the causes were still being investigated as Bond engineers tackled gearbox issues on the aircraft involved in the second crash.
The company’s offices were visited by a range of advisers and experts, Mr Crowther said yesterday.
He added: “They were there to make sure processes within the company had not been violated and also to make sure an incident like that did not happen again.”
Mr Crowther, who was maintenance manager at the time, told the inquiry it did not distract engineers from their day-to-day operations but they were being extra careful.
“People were being very cautious about what they were doing and trying to do everything 110%,” he added.
He was not on duty when problems arose with the doomed helicopter’s gearbox on March 25, 2009, but was kept updated by engineering team leader Steven Milne.
“As the day progressed it looked like a lot of things were building up with that gearbox,” he said.
Initially, it was decided to “put it to one side” and replace it with parts from another helicopter in the hangar.
But that plan changed following troubleshooting advice from aircraft manufacturer Eurocopter, and the helicopter went back into service with the same gearbox the next day.
Mr Crowther said: “We would never fly an aircraft if we had any doubt.”
The inquiry, which is nearing the end of its second week, has been told what happened after the metal fragment was found in the gearbox and monitoring systems on the helicopter highlighted a warning.
Bond’s engineers did not refer to the aircraft’s maintenance manual, which would have led them to carry out an internal inspection of part of the gearbox known as the epicyclic module.
On Tuesday, Mr Crowther said he found it “understandable” there was confusion as Eurocopter’s instructions were ambiguous. But Sheriff Principal Derek Pyle said yesterday there was “no excuse” for not referring to the manual.
Get updates from today’s FAI session at EnergyVoice.com throughout the day, and read full coverage and reaction to yesterday’s sessions in today’s Press and Journal.