The ditching of a Robinson R44 helicopter into the ocean 80 km north of Horn Island shows how good preparation greatly improves the chances of survival and rescue. The ditching took place on 9 June 2012 during a return flight from Dauan Island to Thursday Island.
Earlier that day, on the way to Dauan Island, the helicopter’s alternator light illuminated on two separate occasions. Both times, the pilot turned the alternator off and then back on and the light went out. Later, when the pilot started the engine for the return flight from Dauan Island, the engine rotated several times and made a clicking sound ‘like a battery without enough power’.
After consulting with the operator, the pilot used truck batteries to start the helicopter. He ran the engine at idle power for about 10 minutes before departing for Horn Island.
Fortunately, the pilot had taken precautions before commencing the flight—precautions that enabled him to land the helicopter safely, summon help, and be located by the search and rescue team.
About 10 minutes after departing, the alternator light illuminated again. The pilot turned the alternator off and back on again and the light went out. This happened three more times before the pilot isolated all non-essential electrical systems. By then, he had passed the point of no return to Dauan Island and decided to fly to Moa Island instead. Continued trouble with the engine, however, indicated a possible engine overspeed, so he deployed the helicopter’s emergency ‘pop-out’ floats and landed in one metre of swell. The pop-out floats allow the helicopter to float on the water surface.
Fortunately, the pilot had taken precautions before commencing the flight—precautions that enabled him to land the helicopter safely, summon help, and be located by the search and rescue team.
A few years previously, he had undertaken ditching training, and was prepared for a water landing. After landing safely, he shut down the helicopter and, since the conditions were reasonably stable, remained in the cockpit, wearing a life jacket equipped with flares. He activated his personal locator beacon (PLB) and attempted to contact the Horn Island police on his mobile phone, but the signal dropped out. He then used his mobile phone to contact the helicopter operator, who initiated a search and rescue operation by contacting the Rescue Coordination Centre Australia. Shortly after, the signal from the PLB was detected by the Cospas-Sarsat satellite system. In addition, the pre-arranged SARTIME (a time nominated by the pilot for search and rescue proceedings to begin) was reached, and the automated software initiated.
The crew of the search and rescue helicopter were not able to determine an accurate location from the PLB signal since it remained within the helicopter fuselage, but they navigated to the pilot using the flares that he discharged. The pilot was rescued uninjured; however, the helicopter sustained substantial damage due to the salt water. It was recovered the next day.
A detailed examination of the helicopter following the accident found evidence of an engine overspeed. As a result of this occurrence, the aircraft operator has, among other actions, amended company policy in relation to a flat battery and faulty alternator, requiring immediate replacement. In addition, the lanyard on the PLB has been extended from 0.5 m to 3 m, allowing the PLB to be thrown clear of the helicopter. Pilots have also been briefed in the use of noise-cancelling headsets, after the pilot reported that his headset may have dampened the abnormal engine sounds.
The full report of AO-2012-096 is contained within the Aviation Short Investigation Bulletin – Issue 15.