Originally Posted by The ATSB
On the night of 14 March 2018, Heli-Aust Whitsundays Pty Ltd was operating a twin-engine EC135 P2+ helicopter, registered VH-ZGA, on a flight from its base at Port Hedland, Western Australia. This flight, conducted under the night visual flight rules, was to position the helicopter for a marine pilot transfer (MPT) from an outbound bulk carrier.
The pilot in command was a company instructor who was supervising line training with a recently recruited pilot. Earlier in their rostered shift, the pilot under supervision had passed a line check for day MPT and, having a total of 10 MPT flights, was approved for day operations. The instructor then introduced the pilot under supervision to night MPT operations and they completed 2 night MPT flights.
At 2330 local time, the helicopter was lifted off and climbed on track to the outer markers of the shipping channel (C1/C2), about 39 km from the port. Although the weather was suitable for the flight, there was no moonlight, and artificial lighting in the vicinity of C1/C2 was limited. Consequently, the approach to the ship was conducted in a degraded visual cueing environment that increased the risk of disorientation.
From a cruise altitude of 1,600 ft, the pilot under supervision descended the helicopter to join a right circuit around the carrier at the specified circuit height of 700 ft. During the base segment the helicopter’s altitude started to increase, reaching 850 ft soon after completing the turn onto final at an airspeed of about 70 kt. Although the helicopter was higher than the target height of 500 ft, a consistent descent was not established, and the helicopter remained above the nominal descent profile.
When the helicopter was about 300 m from the landing hatch, it was descending through 500 ft at a rate of about 900 ft/min. At about this point, a go-around was initiated, but the helicopter descended to about 300 ft before a positive climb rate was achieved. The helicopter was turned downwind for another approach and subsequently reached 1,100 ft. A
descent was then initiated without coupling a vertical navigation mode of the autopilot. This was not consistent with standard operational practices and significantly increased the attentional demands on both pilots and associated risk of deviation from circuit procedure. During the downwind and base segment of the circuit, the pilots did not effectively monitor their
flight instruments and the helicopter descended below the standard circuit profile at excessive rate with decaying airspeed. Neither pilot responded to the abnormal flight path or parameters until a radio altimeter alert at 300 ft.
The instructor responded to the radio altimeter alert, reducing the rate of descent from about 1,800 ft/min to 1,300 ft/min. This response was not consistent with an emergency go-around and did not optimise recovery before collision with water.
After the unexpected and significant water impact in dark conditions, the helicopter immediately rolled over, and the cabin submerged then flooded. The instructor escaped through an adjacent hole in the windscreen and used flotation devices until rescued; however, the pilot under supervision was unable to escape the cockpit and did not survive.