Lifting chain caused helicopter to crash during boat move

A helicopter carrying a boat crashed into a Scottish loch, killing the pilot, after the lifting chain flew up “like a kite” and hit the aircraft’s tail rotor.

The boat became unstable and flew upwards as the AS350B2 Ecureuil helicopter was flying over Loch Scadavay on North Uist on 13 June last year. After the lifting line struck the tail rotor, the helicopter became “uncontrollable and descended rapidly into the loch”, an Air Accidents Investigation Branch (AAIB) report found.

Peter Clunas, 59, a pilot from Newburgh in Aberdeenshire with more than 30 years’ experience, suffered a severe head injury and died.

The AAIB report found Mr Clunas had successfully lifted one boat that morning and was asked to fly a second boat, which was smaller and lighter than the first. Asked by air traffic control (ATC) whether he would be doing the second lift, he replied: “They want me to do another lift, but I’m not convinced it’s practical, so I’m just going to assess it and once I know whether I’m going to lift it or not I’ll get back in touch.”

At 9:11am, Mr Clunas radioed to ATC that he was airborne with an underslung load, but a short while later the helicopter crashed.

The pilot appeared to have jettisoned the boat from the helicopter, but investigators said it seems everything happened so fast there was no time for this to have an effect.

The report said: “Eyewitnesses reported that within seconds of boat two spinning, it lifted into the air independently of the helicopter, like a kite.

“It paused momentarily, then lifted further up and over the tail boom of the helicopter. One witness remarked ‘[it] all happened really fast’.” The report said: “The physical characteristics of the boat and the method by which it was carried increased the probability of it becoming unstable.”

The report found the pilot – the only person on board – was wearing a helmet, but the chin strap buckle was not fastened.

The AAIB said since the incident the helicopter operator had taken safety actions mainly relating to operational procedures and training.

It has also temporarily curtailed the carriage of boats, caravans and planes. A spokesman for PDG Aviation Services, the helicopter’s owner and operator, described the report as “very thorough”.

“Although the accident occurred just over a year ago, the passage of time has not made the loss of our pilot any easier to bear and our thoughts especially at this time are with his family and friends,” he said.