An Austrian Airlines de Havilland Dash 8-400, registration OE-LGJ performing flight OS-917 from Vienna to Salzburg (Austria) with 54 passengers and 4 crew, was climbing out of Vienna when the crew stopped the climb at FL150 reporting an unusual odour in the cockpit. The aircraft returned to Vienna for a safe landing on runway 34 about 25 minutes after departure.
The flight was cancelled.
The airline reported the crew returned to Vienna due to an unidentified unusual odour in the cockpit. The passengers were bussed to Salzburg. Maintenance is examining the aircraft, the cause of the odour has not yet been found. The airline added later on May 17th 2017, that the cause has been identified, a defect in the engine compressor caused contamination of the bleed air supplying the cabin. The pilots described the odour like “old socks”.
The occurrence aircraft is still on the ground in Vienna about 33 hours after landing back.
According to background information The Aviation Herald received a defective seal permitted engine oil to enter the bleed air.
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