Narrative:

At FL190 we received a left engine low oil pressure warning. Our checklist required an engine shutdown. Consulted with our company, checked WX in ags, which was the nearest suitable airport, and decided to make an emergency landing in ags, GA. After completing all appropriate checklists, we made a safe and uneventful single engine landing in ags. No injuries and no damage to aircraft were observed. On postflt inspection, found the left engine nacelle covered with oil. Mechanics opened the engine nacelle and found the oil cap was not installed in the filler neck, but was hanging from a safety wire in the compartment. Maintenance deemed this to be the probable cause of the loss of oil pressure.

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Original NASA ASRS Text

Title: AN ATR-72 FLT CREW DIVERTS FOR AN EMER LNDG AFTER SHUTTING DOWN AN ENG FOR LOW OIL PRESSURE.

Narrative: AT FL190 WE RECEIVED A L ENG LOW OIL PRESSURE WARNING. OUR CHKLIST REQUIRED AN ENG SHUTDOWN. CONSULTED WITH OUR COMPANY, CHKED WX IN AGS, WHICH WAS THE NEAREST SUITABLE ARPT, AND DECIDED TO MAKE AN EMER LNDG IN AGS, GA. AFTER COMPLETING ALL APPROPRIATE CHKLISTS, WE MADE A SAFE AND UNEVENTFUL SINGLE ENG LNDG IN AGS. NO INJURIES AND NO DAMAGE TO ACFT WERE OBSERVED. ON POSTFLT INSPECTION, FOUND THE L ENG NACELLE COVERED WITH OIL. MECHS OPENED THE ENG NACELLE AND FOUND THE OIL CAP WAS NOT INSTALLED IN THE FILLER NECK, BUT WAS HANGING FROM A SAFETY WIRE IN THE COMPARTMENT. MAINT DEEMED THIS TO BE THE PROBABLE CAUSE OF THE LOSS OF OIL PRESSURE.

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.