An aircraft electronics expert has told the inquiry into the 2009 Super Puma disaster he was “baffled” by system data for the helicopter just a week before its fatal crash into the North Sea.
Phil Eaton, 53, was senior avionics engineer for operator Bond at the time.
Giving evidence on the 20th day of the fatal accident inquiry in Aberdeen, Mr Eaton said he had never seen anything like what he faced on March 25, 2009, when a colleague showed him unusual helicopter data.
“I was in my office,” he said, adding: “Matthew Smailes (Bond’s health and usage monitoring system, or Hums, adviser) came to me just before 4pm and explained there was something on the ground-station he wanted me to look at.”
Mr Eaton said a computer screen graph for G-REDL, which later crashed killing everyone on board, made no sense.
He added: “I didn’t like the look of the data. It was not like I had ever seen before. I was baffled to be honest. I couldn’t understand what was happening. I found it confusing and we definitely needed to look into it.”
The unusual graph, measuring vibration levels in the gearbox, prompted him to contact helicopter manufacturer Eurocopter for advice.
“I tried to describe as best as I could the data I was seeing,” said Mr Eaton.
Eurocopter then requested screen “dumps”, which Mr Smailes sent to the French company.
After looking at all the information, including the discovery of a tiny metal fragment in G-REDL’s gearbox, Eurocopter Hums expert Brice Fernando sent Bond’s team an e-mail recommending a troubleshooting work card to check for any more metal particles.
The e-mail added: “If nothing abnormal is found, there is no reason to ground the aircraft and you can go flying tomorrow morning.”
Mr Eaton said he only mentioned the metal particle found on detection magnets to Mr Fernando as a “by the way” as his main concern was the erroneous data, which was diagnosed as a ground-station problem.
“The reason for the (initial) phone call was to discuss the anomaly in the main gearbox,” he added.
Special inspections requested by Eurocopter revealed no more fragments and the helicopter continued in service until the tragedy on April 1.
All 16 men on board, including two pilots, died in the accident.
The inquiry has now heard all the evidence.
Final submissions will be made on Thursday in an attempt to establish what went wrong and whether lessons can be learned.