Pilots nearly landed a helicopter on the wrong North Sea platform because they look similar, according to air accident investigators.
Last August, a Bristow-operated helicopter mistakenly made a landing approach to the Brae Bravo platform, seven miles from its actual destination at the Brae Alpha.
The incident prompted an investigation from the Air Accident Investigation Branch (AAIB) who said “decoy characteristics” making the installations look similar contributed to the error.
It was only “at a very late stage” while the aircraft was hovering over the helideck that a radio operator on the Bravo managed to tell the pilots of their mistake.
The helicopter was transporting crew and cargo between different platforms in the Brae field and Bristow highlighted that it completed its mission without any further incident.
Wind direction forced an approach to the platform which could “obscure” the Alpha behind it, according to the AAIB report, while certain approaches can make visual differences between them hard to identify.
Investigators said pilots failed to spot their error as they hadn’t made proper use of navigational equipment during the flight or established the potential for the mistake in pre-flight planning.
The radar was kept on standby during the landing approach, while no reference was made to the “range to the platform”.
However, there were factors including a “very high workload” for the commanding officer, who made the initial mistake while training a junior co-pilot during the mission.
Operations such as crane work and venting of flammable gas need to be stopped during flight arrivals to ensure platforms are safe, bringing a risk during any mistaken landings.
Since this incident, another helicopter also operated by Bristow landed on the wrong platform in the Forties field in March.
The AAIB report into the Brae case said that many of the contributing factors “have previously been identified” as causes of wrong deck landings in the past.
RMT regional organiser Jake Molloy said this questions whether lessons are actually being learned.
He added: “Because of that statement, I don’t know that you could actually proportion blame to the pilots.
“We shouldn’t be having the same types of events as we’ve before, otherwise it makes a mockery of this idea of learning from incidents.
“You’ve then got to ask the helicopter operators why we’re still putting people in a situation that leads to failure.”
A Bristow spokesman highlighted that the S-92 did not actually land on the wrong platform and was able to re-route to the correct installation.
He added: “There was no impact to routine operations as a result of the error, and passengers were flown to the correct installation without further delay.
“Subsequent to this investigation, additional learnings were taken forward into our standard pilot training programme.”
The Brae oilfield lies 170miles north-east of Aberdeen.
At the time of this incident it was operated by Marathon Oil however it has since changed hands to RockRose Energy who completed a deal to buy the US firm’s North Sea business last month.