In-flight propeller loss due to a fatigue fracture

The Australian Transport Safety Bureau’s (ATSB) investigation into the in-flight propeller loss involving a Saab 340B was the result of a fracture of the propeller shaft on the right engine propeller gearbox (PGB).

REX Saab 340B landed safely after In-flight loss of propeller, SW of Sydney NSW, on 17 March 2017

The right propeller separated from the aircraft, with 16 passengers and three crew on board, while it was on approach to Sydney Airport from the south-west on 17 March 2017.

The ATSB found the fracture was due to a fatigue crack that originated in a propeller shaft flange dowel hole and spread through the shaft until it could no longer transmit the loads required to maintain the propeller on the aircraft.

The NSW Police Aviation Support Branch undertook a search operation for the propeller four days later. The propeller was located in dense bushland at Revesby, and airlifted out.

ATSB Chief Commissioner Greg Hood said the investigation was unable to determine, conclusively, what caused the fatigue crack to occur.    

“This was an extremely rare event, and the crew should be commended.”

“The ATSB’s investigation found the crew demonstrated a high level of professionalism in their communication, coordination and application of the safety checklist procedures in their response to the incident, which resulted in an uneventful single-engine landing at the airport,” Mr Hood said.

“This was an extremely rare event, and the crew should be commended.”

Following the incident, the engine manufacturer, General Electric, and the airline, undertook a number of proactive safety actions.

“The airline and the engine’s manufacturer have undertaken a number of proactive safety actions, such as the release of new service bulletins and airworthiness directives, and changes to their maintenance regime, to reduce the risk of this extremely rare event from occurring again,” Mr Hood said.

“Flying remains as one of the safest forms of travel for the public. Here in Australia, we have one of the best aviation safety records in the world.”

Read the investigation report, AO-2017-032: In-flight loss of propeller involving Saab 340B, VH-NRX, SW of Sydney Airport, NSW, on 17 March 2017

Last update 16 November 2018