Investigation finds no clear reason for helicopter crash, families call for ban

Thursday, 25 August 2016

The scene of the crash which claimed two lives in February 2015.

An investigation into a Queenstown helicopter crash that killed two people has found no clear reason for the incident.

On 19 February 2015 a training flight returning to Queenstown crashed into bush near the Lochy River. Instructor Stephen Combe and 18-year-old instructee James Patterson-Gardner were both killed.

The Transport Accident Investigation Commission (TAIC) report into the crash concluded that the helicopter broke apart in mid-air due to the rotor blades striking the cabin.

This is known as 'mast bumping'. It is typically the result of turbulence, sudden movement, a slowing rotor, a 'low-gravity situation', or some combination thereof.

Victim of the helicopter crash, Stephen Combe.

Victim of the crash James Louis Patterson Gardner, left, with John Key.

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The wreckage of the crash seen from above.

The TAIC report could find no pre-existing mechanical defect or failure in the Robinson R44 helicopter to blame. The only scenario deemed 'about as likely as not' involved turbulence.

While the weather was calm and suitable for flying, the report found there could have been small pockets of turbulence in the area.

These pockets of turbulence, when combined with a relatively high flight speed and a pilot's response to the turbulence, would have a high risk of causing a low-gravity situation, causing the helicopter to the roll rapidly to the right, letting the rotors hit the cabin before the pilot had time to react.

Low-gravity situations cause pilots to feel temporarily 'weightless' and typically occur when helicopters fall suddenly or stall.

It was not clear whether the student or instructor was piloting the craft at the time.

'Flying at 100 knots or more and encountering a pocket of turbulence while under the control a low-flying-time student pilot is [a] reasonably high-risk situation,' the report stated.

Instructor Combe had 4527 hours of flight experience, while student Patterson-Gardner had 10.

Because of the lack of clarity, the TAIC has called for cockpit video recorders or other forms of data capture to be promoted - much like the 'black box' mandated in commercial jets.

CALL FOR ROBINSON HELICOPTERS TO BE BANNED

The families of the victims issued a joint response to the report, calling for Robinson helicopters with the same rotor design to be banned.

'Nothing will bring back Steve and James nor the other victims of the many in-flight breakups of this aircraft type. Other Robinson accidents have been blamed on turbulence or pilot inexperience.'

'In our case, the instructor was experienced and from the tracking data, the aircraft was being flown in the cruise, in calm weather and at a safe altitude.'

'We firmly believe that had Steve and James been in any other aircraft type the accident would not have occurred. Our families are traumatised and have paid the ultimate price. We do not want other families to suffer this too.'

Robinson helicopters are very common in New Zealand, making up around 40 per cent of the New Zealand fleet in 2014.

The three main Robinson helicopter variants available all used the same rotor system.

While the report ruled out pre-existing mechanical failure, it did note the prevalence of these types of crashes.

'There have been many other fatal mast bump accidents involving Robinson helicopters in New Zealand and around the world that have gone largely unexplained. It is difficult to identify the lessons from an accident and make meaningful recommendations to prevent similar accidents if the underlying causes cannot be determined.'

The Robinson R22 has been involved in 95 accidents since 2000. The crashes have resulted in 19 deaths.

'This is a serious safety issue that the industry, including pilots, operators, the manufacturer and the regulator, will need to address.'

The Civil Aviation Authority in 2015 upped the amount of training hours needed before a pilot flew a R22 or R44 solo.

Over The Top, who flew the helicopter involved in the crash, has stopped using Robinson aircraft.

'The aircraft in the accident was a properly maintained R44 which had been used as part of its commercial fleet. Over The Top has no intention to use Robinson aircraft again for any future operation.'

Patterson-Gardner was the son of the Over the Top's owner.