Narrative:

On descent into ZZZ the left engine lost oil quantity. Other indications were normal. It then began to vibrate for several seconds and then smoothed out. As a precaution we declared an emergency; and received a vector directly to ZZZ; where we made an uneventful landing.

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Original NASA ASRS Text

Title: A319 FLT CREW DECLARES EMER DUE TO ZERO OIL QUANTITY INDICATION AND VIBRATION OF L ENG.

Narrative: ON DSCNT INTO ZZZ THE L ENG LOST OIL QUANTITY. OTHER INDICATIONS WERE NORMAL. IT THEN BEGAN TO VIBRATE FOR SEVERAL SECONDS AND THEN SMOOTHED OUT. AS A PRECAUTION WE DECLARED AN EMER; AND RECEIVED A VECTOR DIRECTLY TO ZZZ; WHERE WE MADE AN UNEVENTFUL LNDG.

Data retrieved from NASA's ASRS site as of January 2009 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.