Incident Overview
On 8 October 2025, a Robinson R44 Raven I helicopter, registered VH-XSO and operated by GBR Helicopters, departed Thursday Island, Queensland, with a pilot and two passengers on board. While cruising at approximately 600 ft above sea level, the low rotor RPM horn activated. The pilot entered an autorotation and subsequently conducted a ditching into the ocean. Upon water impact, the helicopter immediately rolled onto its left side, and the front left seat passenger egressed underwater.
Engine Power Loss
The pilot reported that during the cruise, the low rotor RPM horn activated, the engine RPM reduced, and the engine completely stopped prior to ditching. The last recorded data point from the operator’s flight tracking software indicated ‘engine off’. The helicopter sank and was not recovered, preventing determination of the cause of the engine power loss. The investigation identified that, for reasons undetermined, the helicopter engine experienced a total power loss while in cruise over water, necessitating the ditching.
Pre-Flight Briefing and Brace Positions
The pilot provided a pre-flight safety briefing covering door operation as an emergency exit, alternative exits if a door was blocked, and lifejacket use. However, the pilot did not brief the passengers on the correct brace position as required by the operator’s manual and regulations. During the autorotation, the pilot advised both passengers to brace. The front left passenger grabbed the pilot’s arm and sat back in their seat, while the rear seat passenger braced using the cross bar on the back of the pilot’s seat. The operator noted that the helicopter contained safety briefing cards depicting the brace position for the installed lap and sash harness, but one passenger was unaware of the card’s location. The lack of briefing on the appropriate brace position increased the risk of injury to the occupants.
Emergency Response
Realizing the need to ditch, the pilot transmitted a MAYDAY call, which alerted another helicopter. That helicopter diverted to the ditched aircraft, and together with a nearby fixed-wing aircraft, communicated the emergency to Brisbane Centre air traffic control, providing the location and reducing search and rescue response time. The helicopter’s automatic emergency locator transmitter (ELT) also alerted the Joint Rescue Coordination Centre to the last known position. The pilot deployed the emergency pop-out floats in preparation for the water landing, which very likely prevented rapid sinking and gave occupants time to egress. Although the helicopter rolled shortly after ditching, the partially submerged structure provided some refuge and aided visual identification by first responders. The pilot’s advisory to brace prior to water impact, even though not in the correct position, likely gave passengers additional time to prepare for egress.
Injuries and Rescue
All three occupants sustained serious injuries from chemical burns caused by fuel in the water while waiting for rescue. One occupant was additionally injured from impact with the wreckage during rescue winching operations.