Narrative:

Flight departed dtw en route to cvg. Over rosewood VOR, the captain noted that our left engine oil quantity had decreased to approximately 5 quarts. We ran the 'oil quantity decreasing' procedure in our cockpit operating manual. All other indications were normal. We declared an emergency with center and proceeded to cincinnati for a visual approach to runway 18L. It was found upon inspection at the gate that the oil cap for the left engine was unsecured and that the oil was allowed to escape.

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Original NASA ASRS Text

Title: A DC9 CREW, AFTER DEPARTING DTW, DURING CLB, NOTICED THE L ENG OIL QUANTITY LOW. AN EMER WAS DECLARED, INCLUDING A RETURN TO DTW.

Narrative: FLT DEPARTED DTW ENRTE TO CVG. OVER ROSEWOOD VOR, THE CAPT NOTED THAT OUR L ENG OIL QUANTITY HAD DECREASED TO APPROX 5 QUARTS. WE RAN THE 'OIL QUANTITY DECREASING' PROC IN OUR COCKPIT OPERATING MANUAL. ALL OTHER INDICATIONS WERE NORMAL. WE DECLARED AN EMER WITH CTR AND PROCEEDED TO CINCINNATI FOR A VISUAL APCH TO RWY 18L. IT WAS FOUND UPON INSPECTION AT THE GATE THAT THE OIL CAP FOR THE L ENG WAS UNSECURED AND THAT THE OIL WAS ALLOWED TO ESCAPE.

Data retrieved from NASA's ASRS site as of July 2007 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.