Narrative:

On climbout through approximately FL190 I noticed erratic engine oil pressure on the left hand engine. We complied with QRH; conferred with dispatch; and returned to departure airport. After being cleared to land on short final; we received an intermittent left-hand engine oil low pressure red warning and executed a 'normal' landing. Upon clearing the runway the oil pressure warning that was intermittent became steady and we shut down the left-hand engine on taxi in. The initial diagnosis from the mechanic that inspected the aircraft was excessive oil loss due to a mechanic not installing o-rings on an air turbine starter change the day prior.

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Original NASA ASRS Text

Title: CRJ200 Captain detects erratic oil pressure during climbout and elects to return to the departure airport. The oil pressure warning is flashing during approach and comes on steady after landing and the engine is shut down. Maintenance discovers O-rings were omitted on an air turbine starter change the day prior.

Narrative: On climbout through approximately FL190 I noticed erratic engine oil pressure on the left hand engine. We complied with QRH; conferred with Dispatch; and returned to departure airport. After being cleared to land on short final; we received an intermittent left-hand engine oil low pressure red warning and executed a 'normal' landing. Upon clearing the runway the oil pressure warning that was intermittent became steady and we shut down the left-hand engine on taxi in. The initial diagnosis from the Mechanic that inspected the aircraft was excessive oil loss due to a mechanic not installing O-rings on an air turbine starter change the day prior.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.