What happened
On 8 October 2025, a Robinson R44 Raven I, registered VH-XSO, departed Thursday Island, Queensland, carrying a pilot and two passengers. While cruising at approximately 600 feet above sea level, the pilot heard the low rotor RPM horn, followed by a complete loss of engine power.
In response to the engine failure, the pilot performed a ditching in the ocean. During the impact, the helicopter's left float detached, causing the aircraft to roll onto its left side. The front left passenger managed to exit the aircraft underwater. All 3 occupants sustained serious injuries, including chemical burns from fuel in the water. Additionally, one individual suffered an injury from striking the wreckage during the rescue winching process.
The investigation
The ATSB examined the circumstances surrounding the engine failure and the subsequent survivability of the occupants. Investigators found that the engine power loss occurred for undetermined reasons, making it impossible to identify the specific cause of the failure.
While the pilot successfully deployed the emergency pop-out floats—which likely prevented the aircraft from sinking immediately—the detachment of the left float during the ditching significantly compromised the stability of the aircraft. The investigation also looked into the effectiveness of the emergency response, noting that the pilot's timely MAYDAY call and the activation of the ELT were critical in alerting rescue services.
Findings
- The primary cause of the ditching was an undetermined total loss of engine power during cruise.
- The detachment of the left float during the water landing caused the aircraft to roll, increasing the difficulty of egress and exposing passengers to fuel-related chemical burns.
- The pilot's pre-flight safety briefing failed to instruct passengers on the correct brace position, which increased the risk of injury and could have hindered the pilot's control of the aircraft.
- The pilot's effective MAYDAY transmission and the use of pop-out floats were key factors in the occupants' survival.
Safety message
- The operator's failure to provide pilots with survival emergency locator transmitters for overwater flights is a safety issue that reduces post-impact survivability.
- The lack of Helicopter Underwater Escape Training (HUET) for regular overwater passengers represents a significant safety risk regarding drowning hazards.