Jump to Content

Airbus A330 in-flight engine shut down

Airbus A330 in-flight engine shut down

The failure of an air turbine starter led to the in-flight shutdown of the number one engine of a China Airlines Airbus A330 aircraft in October 2013. (An air turbine starter uses pressurised air to rotate the high-pressure rotor within the engine during the engine start sequence).

The incident occurred approximately four hours into a flight from Sydney to Taipei, Taiwan ROC. The flight crew completed a precautionary shutdown of the number one engine in response to a low oil pressure warning, and diverted the flight to Cairns, Queensland.

The ATSB investigation found that the air turbine starter had sustained an uncontained failure. When the starter failed, an oil scavenge pipe from the number one engine was severed by debris that had not been contained by the starter casing. This resulted in a rapid loss of oil that required the number one engine to be shutdown.

The investigation identified that the starter failure was due to the failure of the output shaft bearing. Damage to the bearing was consistent with exposure to transient loads from the crash engagement of the starter clutch during engine starts, or, from axial loads to the bearing from the horizontal driveshaft.

Safety actions taken

To eliminate the potential for crash engagements to occur during operation of the air turbine starter, the starter manufacturer was phasing out the single pawl and ratchet clutch mechanism. A redesigned air starter using a full range pawl and ratchet is being incorporated into service. The manufacturer has also initiated changes to limit the potential for axial loads to be applied to the output shaft bearing of the turbine stater.

The resulting changes in design will eliminate air turbine starter failures associated with crash engagements, though they will not completely eliminate the potential for failures to occur (contained or otherwise).

Other safety action from the starter manufacturer, the engine manufacturer, and the operator includes a number of changes to the procedures for oil level checks and changes.

The ATSB is satisfied that the likely reoccurrence of this failure mode will remain low as a result of these safety actions.

Read the investigation report AO-2013-172

 
Share this page Comment
Last update 10 December 2015