TAIC report finds door removal, turbulence, but not cannabis contributed to deadly Port Hills helicopter crash

The TAIC investigation into the death of David Steven Askin, known as Steve, was finally released late last month.

The investigation revealed some of the doors of his helicopter had been removed “to give him a better view” while he fought a massive wildfire above Christchurch.

Turbulence was also found to be a factor but TAIC found that “it was very unlikely that Askin was impaired by his recent use of cannabis.”

The organisation did reiterate, however, that the use of cannabis was a serious risk to aviation safety.

New Zealand’s media covered the story closely as Steve was a former SAS soldier who received New Zealand’s second highest medal for bravery and was once injured in a Taliban shootout. Stuff reported that the 38-year-old had been working for Way To Go Heliservices when he crashed near Sugarloaf while fighting a massive fire in the Port Hills on February 14, 2017.

The report said the monsoon bucket’s suspension had contacted the helicopter’s tail rotor while Steve was returning to a dipping pond to fill the bucket. The damage to the tail rotor caused the vertical stabiliser to tear off the tail boom, and the helicopter became uncontrollable and crashed.

Stuff reported that a video recording taken from a camera mounted underneath the helicopter showed the monsoon bucket rising towards the tail rotor. The video also showed an object had fallen from the helicopter shortly beforehand. It was “virtually certain” the object was the dislodged window, the investigation found. Askin had experienced a similar incident while flying the same helicopter on a firefighting mission in 2015.

The TAIC report also said that the helicopter was fitted with sliding doors on the left side of the cabin and standard doors on the right side. All the doors on the right side had been removed “to give Askin a better view of the underslung bucket while firefighting, and the doors on the left side were closed.”

A supplement to the flight manual said such a door configuration was prohibited. Way To Go Heliservices said the supplement was ambiguous and it was not aware the configuration was prohibited.

The door configuration meant there was fluctuating pressure inside the cabin as the helicopter encountered turbulence and wind shear.

The investigation found that it was “very likely” that the window panel was dislodged from the door by a sudden increase in air loading due to turbulence or a change in airspeed. The dislodging of the window would have caused a sudden change in airflow through the cabin and an increase in noise and a sharp sound.

Although not directly contributing to the crash, TAIC found three deficiencies that indicated the helicopter operator’s quality assurance system should be reviewed.

An interim report released last May revealed Steve had made a mayday call moments before his Eurocopter AS350-BA ‘Squirrel’ went down.

Two safety issues were identified in the inquiry – the first being a lack awareness within the helicopter industry of the additional risks involved with underslung load operations. The second was that Way To Go Heliservices did not have adequate systems allowing the pilot to determine the total weight and balance of the helicopter for the firefighting operation.

The report also found that the operator did not ensure that incidents such as the previous loss of a window were recorded, notified to the Civil Aviation Authority, and investigated.

Way To Go Heliservices have so far made no comment on the TAIC report.

For more about Steve and the full Stuff article see HERE.

The TAIC report and related documents can be found HERE.