On 22 November 2014, at about 0600 Eastern Standard Time, a Robinson R44 helicopter, registered VH-YYS, departed from Mareeba, Queensland on a private flight with a pilot and one passenger on board. The helicopter engine had recently been overhauled, and the pilot had expressed concern about the quantity of oil the engine was using following the overhaul. He had been advised to conduct a longer flight to ‘bed in’ the engine.
The helicopter tracked via the coast to Cooktown where the pilot landed and refuelled. The helicopter had used about 1 L of oil during the 1.5 hour flight. From there the helicopter continued to Coen with two intermediate landings. In Coen, the pilot refuelled the helicopter and added 1 L of oil to bring the total oil quantity back up to 8 L. The helicopter then tracked to Archer River and departed there at about 1400, tracking towards the coast.
When about 30 NM from Archer River and at about 1,300 ft, the pilot observed the engine revolutions per minute (rpm) decreasing rapidly. He immediately entered an autorotation and advised the passenger to brace for impact. The pilot sighted a clearing ahead landed.
The pilot and passenger quickly exited and observed smoke billowing from the rear of the helicopter, where heat from the helicopter’s exhaust ignited a grass fire. Within seconds the helicopter was engulfed by fire and destroyed. The pilot and passenger were uninjured.
A full strip down of the engine was not conducted following the accident. The magnetos were badly fire damaged and it was not possible to determine their serviceability at the time of the accident or the cause of the reduced engine rpm.
In this incident, the pilot was concerned about the serviceability of the helicopter. The cause of the power loss was unable to be determined. The incident highlights the importance of pilot decision making in determining whether to conduct or continue a flight when abnormal indications such as excessive oil consumption occur.