At about 0806 Eastern Standard Time on 15 June 2010 a Piper PA-31P-350 Mojave aircraft, registered VH-PGW, with a pilot and a flight nurse on board, collided with terrain in a suburban area about 6 km north-west of Bankstown Airport, New South Wales. At the time of the accident, the pilot was attempting to return to Bankstown following a reported in-flight engine shutdown. Both occupants were fatally injured and the aircraft was destroyed by the impact forces and an intense post-impact fire.
What the ATSB found
The Australian Transport Safety Bureau (ATSB) found that following the shut down of the right engine, the aircraft’s airspeed and rate of descent were not optimised for one engine inoperative flight. In addition, spectral analysis indicated it was unlikely that the left engine was being operated at maximum continuous power as the aircraft descended. As a result, the aircraft descended to a low altitude over a suburban area and the pilot was then unable to maintain level flight, which led to the collision with terrain.
Examination of the engines, propellers and governors and other aircraft components found no evidence of any pre-impact faults. However, the engine surging identified by the spectral analysis of radio transmissions during the flight was consistent with uneven fuel distribution to the cylinders.
What has been done as a result
The Civil Aviation Safety Authority has started a project to amend advisory material relating to multi-engine aircraft training and operations to include guidance information about engine problems encountered during the climb and cruise phases of flight. This amended guidance material will include information about aircraft handling, engine management, and decision making during these phases of flight.
This accident reinforces the importance when flying twin-engine aircraft with one engine shutdown that the optimal speed be selected, along with maximum continuous power on the operative engine, and that the aircraft’s performance should be verified prior to conducting a descent. Pilots should also use the appropriate PAN or MAYDAY phraseology when advising air traffic control of non-normal or emergency situations.