Narrative:

In the climb out the crew became aware of an oily smell in the cabin that did not dissipate but got stronger. Confirmed by the flight attendants and both pilots; we returned to the departure airport for landing and passenger removal. The pilots used our oxygen mask once the smell was identified and started the APU selecting it to supply the bleed air for the air conditioning packs to help vent the cabin while returning to land. After landing taxi to the gate to deplane passengers with out any injuries; smelled as if oil was being vaporized in the air that we were breathing.

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Original NASA ASRS Text

Title: An A319 crew detected a diesel bus exhaust odor as thrust was reduced for a climb constraint so they went on oxygen immediately; declared an emergency and returned to the departure airport where a CFM56 bent compressor section blade was found which caused a slight shaft wobble.

Narrative: In the climb out the crew became aware of an oily smell in the cabin that did not dissipate but got stronger. Confirmed by the flight attendants and both pilots; we returned to the departure airport for landing and passenger removal. The pilots used our oxygen mask once the smell was identified and started the APU selecting it to supply the bleed air for the air conditioning packs to help vent the cabin while returning to land. After landing taxi to the gate to deplane passengers with out any injuries; smelled as if oil was being vaporized in the air that we were breathing.

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.