Bucket f lew towards tail before fatal crash
The Transport Accident Investigation Commission (TAIC) yesterday released an interim report into the fatal helicopter crash during the Port Hills firefighting efforts in Christchurch.
It wanted to warn other pilots about what happened and to try to prevent similar crashes.
David Steven Askin, known as Steve, was killed when his helicopter crashed near Sugarloaf while fighting a massive fire on February 14. The 38-year-old former SAS soldier had been working for Way To Go Heliservices.
The report revealed Askin made a mayday call moments before his Eurocopter AS350-BA went down.
A digital video camera on the machine showed the monsoon bucket had flown up towards the tail while the helicopter was returning to a dipping pond.
‘‘The video also showed that the bucket had not contacted the ground prior to the tail rotor strike. After the vertical stabiliser detached, the helicopter had entered a gradual descending right roll until it struck the ground,’’ the TAIC report said.
The helicopter had hit a steep slope covered in tussock. Main rotor strikes on the slope indicated the helicopter had tumbled further down the slope.
The report considered evidence from similar squirrel helicopter crashes, noting the main causes were either an abrupt dive or the bursting of a container carrying a load, which behaves like a parachute when empty.
In both cases, the sling or load had followed the airstream into the helicopter’s tail rotor.
TAIC recommended several solutions, including using heavy ballast slings, and having someone monitor the operation from the ground.