Narrative:

The pilot took off from runway 22L. The oil temperature and pressure both in green arc during taxi/run-up and hold short engine instrument scan. The oil pressure started falling on upwind and when the aircraft was given clearance to turn to the desired heading at 2300 ft; the oil pressure fell from green arc when airplane was cruising at 3700 ft MSL. There was instantaneous rise in oil temperature. Pilot decided to turn back to the airport. After calling up the tower to request permission to return to the airport; oil pressure/temperature were about to touch red arc; pilot expected engine failure and declared emergency. Pilot made it safely back to the runway and taxied out. The tower had fire trucks ready in case of a crash. The pilot squawked the airplane and spoke to maintenance about it.

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Original NASA ASRS Text

Title: DA20 PLT EXPERIENCES LOW OIL PRESSURE IN UNSPECIFIED ENGINE SHORTLY AFTER TKOF. DECLARES EMERGENCY AND RETURNS TO DEP ARPT.

Narrative: THE PLT TOOK OFF FROM RWY 22L. THE OIL TEMP AND PRESSURE BOTH IN GREEN ARC DURING TAXI/RUN-UP AND HOLD SHORT ENG INST SCAN. THE OIL PRESSURE STARTED FALLING ON UPWIND AND WHEN THE ACFT WAS GIVEN CLRNC TO TURN TO THE DESIRED HDG AT 2300 FT; THE OIL PRESSURE FELL FROM GREEN ARC WHEN AIRPLANE WAS CRUISING AT 3700 FT MSL. THERE WAS INSTANTANEOUS RISE IN OIL TEMP. PLT DECIDED TO TURN BACK TO THE ARPT. AFTER CALLING UP THE TWR TO REQUEST PERMISSION TO RETURN TO THE ARPT; OIL PRESSURE/TEMP WERE ABOUT TO TOUCH RED ARC; PLT EXPECTED ENG FAILURE AND DECLARED EMER. PLT MADE IT SAFELY BACK TO THE RWY AND TAXIED OUT. THE TWR HAD FIRE TRUCKS READY IN CASE OF A CRASH. THE PLT SQUAWKED THE AIRPLANE AND SPOKE TO MAINT ABOUT IT.

Data retrieved from NASA's ASRS site as of May 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.