Regional Express (Rex) has grounded five of its Saab 340B turboprop aircraft after the propeller fell off one of the planes as it came in to land at Sydney airport last Friday.

Flight ZL768 from Albury to Sydney, with 16 passengers and 3 crew on board, was at 6,000 feet, 25km south west of Sydney on March 17 when right-hand propeller separated from its shaft.

The propeller sheared off at the shaft and miraculously did not hit the plane. It has not yet been found, but is believed to have fallen somewhere around the Camden area.

The plane managed to land safely on one engine in 35 knot winds and bad weather after being given priority landing. No one was injured.

The Australian Transport Safety Bureau (ATSB) is investigating and the aircraft has been quarantined.

Rex says that the engine had already been shut down by the crew following abnormal indications during the flight and the propeller was feathered to reduce drag. The First Officer saw the propeller assembly separate from its shaft, rotating upwards and to the right in a horizontal position, moving away from the aircraft without making contact.

Today the airline had a change of heart about grounding the fleet as a precaution and said that while it was waiting for the ATSB to determine the cause of the accident it would withdraw from service an additional five planes with the propeller gear boxes and shafts from the same series as the plane involved.

Rex is Australia’s largest independent regional airline, with more than 50 Saab 340 aircraft on 1,500 weekly flights.

Rex chief operating officer Neville Howell said the Saab 340 is designed operate effectively on one engine.

“This is an extremely rare event and the only other recorded similar event was in 1991 when US carrier Comair’s aircraft also landed safely after a separation of its propeller,” he said.

“The crew demonstrated enormous composure and discipline under extraordinary circumstances, and I commend their professionalism. The Captain displayed exceptional skills in landing the aircraft so smoothly in bad weather and strong winds, so much so that the passengers did not notice anything different.”

Rex has been in contact with Saab and the engine manufacturer, General Electric following the incident.

The company expects some schedule disruptions following the grounding of the additional five planes.

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