Helicopter nose-dived into ground at military port, crash report reveals

A HELICOPTER had to be scrapped after it crashed while taking off at the Marchwood military port, an accident report has revealed.

Almost immediately after leaving the ground to check its hovering capabilities, the Sikorsky S-61N Sea King pitched nose-down and struck the surface before it came to rest on its landing gear.

An Air Accident Investigation Branch (AAIB) report said the commander and co-pilot on-board described how they “felt a thump through the seats” when it hit with the tarmac.

“The main wheels made ground contact causing the tail to pivot downwards onto the tailwheel,” the AAIB said. “The time between the last wheel leaving the ground and the initial impact was less than three seconds.

“Despite the co-pilot being slightly dazed he commenced the emergency shutdown checklist and called to the commander to apply the rotor brake.

“Both pilots then evacuated the helicopter and, once outside, went to check that the engineers were unhurt. There were no injuries.”

The incident resulted in the front equipment bay of the commercial helicopter being crushed and the bay door becoming detached, the AAIB said.

The helicopter operated in the Falklands for four years until late December 2017 when it was transferred by ship to Marchwood.

It had its main and tail rotor blades removed and no covers were used to protect the rotor head and transmission before it was unloaded at Marchwood in late January 2018.

The day following its arrival at Marchwood it was prepared for flight – which included fitting its steel main and tail rotor blades – and a ground run was performed by flight crew.

The plan had been to have the hover check on 1st February 2018 and fly the helicopter to Bournemouth Airport to be refuelled before continuing on to the operator’s base in Newquay.

The AAIB report into the incident put it down to mechanical issues caused mainly by the helicopter being inactive during its transportation.

Also, it said safety checks had not been undertaken and the two crew did not do all the pre-flight checks they should have.

“The investigation found the spherical bearing within the swashplate had seized as a result of corrosion, compounded by inactivity during the voyage from the Falkland Islands,” the AAIB said.

“The checks prior to the flight did not identify the control restriction,” the AAIB said, and the helicopter was “damaged beyond economical repair”.

The report noted there were “time pressures” on the crew because they had to rely on a number of external batteries as no external power cart was available.

Recording data from the flight revealed the commander said there was “not time” to do a “full and free” check of the helicopter.

Having been asked to review recordings of a number of helicopter flights, the operator – which was not named in the report – told the AAIB its pilots did not always do the full pre-flight checks they should.

The operator has since issued instruction to its crew to conduct full checks and pledged it will “continue to monitor” its pilots.

Helicopters transferred by sea will now go through its maintenance section on arrival in the UK, and it has investigated better protection for its helicopters during voyages.

The helicopter manufacturer has also issued safety advice to highlight the necessity of full pre-flight checks.