The ATSB’s investigation into the engine failure and forced landing of a Beech Aircraft 76 Duchess highlights the importance of correctly configuring a multi-engine aircraft following an engine failure.
The accident occurred on 1 June 2018, when the aircraft was conducting a private flight to Cessnock Airport, NSW, with a pilot and two passengers on board.
During the descent at night, the pilot felt the aircraft yaw toward the right and observed the right engine indications showing a loss of power. The pilot immediately commenced the engine failure checklist and configured the aircraft for single-engine flight. As part of that process, the pilot moved the propeller control to the feather position, but did not confirm that the right propeller had actually feathered. The aircraft could not maintain altitude and continued to descend, even after the pilot increased power on the left engine to maximum.
As the aircraft descended through about 5,500 ft, the pilot calculated it would not be able to clear the high terrain between its position and Cessnock. The pilot declared MAYDAY, and after advising air traffic control, elected to conduct a forced landing.
With no intercom-connected headsets to communicate with the passengers, the pilot did not attempt to warn them of the impending forced landing and focused on flying the aircraft.
The aircraft landed in a grassy field with the landing gear retracted. The pilot and passengers were not injured. However, the aircraft was substantially damaged.
The ATSB investigation found that, after the right engine failed, the propeller was not feathered, or did not feather. The increased drag of the unfeathered propeller prevented the aircraft from maintaining altitude, leading to the necessity of a forced landing.
The report highlights the importance of correctly configuring a multi-engine aircraft following an engine failure, and highlights the recurring safety concern of carburettor icing.
The report also confirms the importance of conducting pre-flight passenger safety briefings. In this occurrence, the passengers were not briefed before the flight, nor were they warned about the impending forced landing.
Read the report: Engine failure and forced landing of Beech Aircraft 76, VH-BDS, 49km north-west of Cessnock Airport, New South Wales, on 1 June 2018