Research of accidents into water has shown that occupants who survive the initial impact will likely have to make an in-water or underwater escape, as helicopters usually rapidly roll inverted post-impact. The research has also shown that drowning is the primary cause of death following a helicopter accident into water.
Sonar image of helicopter on seabed
Source: Pilbara Ports Authority and contractors working on their behalf
What happened
On 14 March 2018, at about 2330 Western Standard Time, an Eurocopter EC135 helicopter, registered VH‑ZGA departed Port Hedland Heliport, Western Australia to collect a marine pilot from a departing ship.
The flight was conducted at night under the Visual Flight Rules. A pilot, recently employed by the operator, was flying the helicopter, under the supervision of a training and checking pilot.
At about 2348, the helicopter was operating in vicinity of the ship when it descended and collided with the water. The training and checking pilot escaped from the helicopter and was rescued a short time later. The location of the other pilot was unknown, and a search commenced.
On 17 March 2018, the helicopter wreckage was located on the seabed and the missing pilot was found inside.
Why did it happen
The ATSB investigation is continuing. The ATSB emphasises that it is too soon to conclude factors involved in the pilot under check not surviving the accident.
Notwithstanding, HUET (helicopter underwater escape training) is considered to provide individuals with familiarity with the crash environment and confidence in their ability to cope with the emergency situation. Interviews with survivors from helicopter accidents requiring underwater escape frequently mention they considered that HUET had been very important in their survival. Training provided reflex conditioning, a behaviour pattern to follow, reduced confusion, and reduced panic.
The training and checking pilot had completed a HUET course within the previous 3 years. Although the pilot under check had completed a HUET course, that training was conducted 9 years ago.
Safety advisory notice
AO-2018-022-SAN-001: The Australian Transport Safety Bureau advises helicopter operators involved in overwater operations of the importance of undertaking regular HUET for all crew and regular passengers to increase their survivability in the event of an in-water accident or ditching.
Regular training can assist survivability
Regular HUET courses can assist occupants following a ditching or water impact. That training enables them to practice the techniques to make an in-water or underwater escape from a cockpit or cabin.
Safety advisory notice video statement
Read more about this ATSB investigation: AO-2018-022.