Narrative:

During cruise on a flight from lft to dfw, we received a warning of low oil pressure in the left engine. Followed company checklist procedures and called company. We diverted to txk and declared emergency with center. Upon arrival at txk, we were sequenced #2 behind another aircraft on approach to runway 31. We informed center that we needed to land on runway 4, as it was longer and straight in. We were told to execute a left 360 degree turn. We questioned this with center, but he said it was necessary for separation. We reluctantly complied since we did not have a need to land immediately. I felt that this was not acceptable, as we were an emergency. The controller should have instructed txk tower to make the other aircraft go around. In txk, maintenance inspected engine, and added 4 quarts of oil. We ran up the engine and again inspected it. No leaks, and maintenance control showed no high consumption history. The run-up showed nominal oil pressure. It was noted that the oil sight gauge was very dark, and it looked as if it were full of oil when it wasn't. Maintenance is responsible for checking oil levels, although flcs do for safety's sake. My first officer said he had checked the oil levels, and he thought they were full. The dirty/dark sight gauge had fooled him, and probably maintenance as well. The sight gauges should be kept clean or replaced if they become difficult to read.

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Original NASA ASRS Text

Title: AN EMB120 FLC DIVERTS TO AN ALTERNATE WHEN THE L ENG INDICATES IT IS LOW ON OIL.

Narrative: DURING CRUISE ON A FLT FROM LFT TO DFW, WE RECEIVED A WARNING OF LOW OIL PRESSURE IN THE L ENG. FOLLOWED COMPANY CHKLIST PROCS AND CALLED COMPANY. WE DIVERTED TO TXK AND DECLARED EMER WITH CTR. UPON ARR AT TXK, WE WERE SEQUENCED #2 BEHIND ANOTHER ACFT ON APCH TO RWY 31. WE INFORMED CTR THAT WE NEEDED TO LAND ON RWY 4, AS IT WAS LONGER AND STRAIGHT IN. WE WERE TOLD TO EXECUTE A L 360 DEG TURN. WE QUESTIONED THIS WITH CTR, BUT HE SAID IT WAS NECESSARY FOR SEPARATION. WE RELUCTANTLY COMPLIED SINCE WE DID NOT HAVE A NEED TO LAND IMMEDIATELY. I FELT THAT THIS WAS NOT ACCEPTABLE, AS WE WERE AN EMER. THE CTLR SHOULD HAVE INSTRUCTED TXK TWR TO MAKE THE OTHER ACFT GO AROUND. IN TXK, MAINT INSPECTED ENG, AND ADDED 4 QUARTS OF OIL. WE RAN UP THE ENG AND AGAIN INSPECTED IT. NO LEAKS, AND MAINT CTL SHOWED NO HIGH CONSUMPTION HISTORY. THE RUN-UP SHOWED NOMINAL OIL PRESSURE. IT WAS NOTED THAT THE OIL SIGHT GAUGE WAS VERY DARK, AND IT LOOKED AS IF IT WERE FULL OF OIL WHEN IT WASN'T. MAINT IS RESPONSIBLE FOR CHKING OIL LEVELS, ALTHOUGH FLCS DO FOR SAFETY'S SAKE. MY FO SAID HE HAD CHKED THE OIL LEVELS, AND HE THOUGHT THEY WERE FULL. THE DIRTY/DARK SIGHT GAUGE HAD FOOLED HIM, AND PROBABLY MAINT AS WELL. THE SIGHT GAUGES SHOULD BE KEPT CLEAN OR REPLACED IF THEY BECOME DIFFICULT TO READ.

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.