Narrative:

TRACON handed me off to the ZZZ tower; from whom I requested an SVFR return. The tower instructed me to hold in VMC 5 mi east of the airport until cleared to continue to land. I orbited at 2000 ft; 2200 RPM; approximately 85 KTS; in a shallow bank. After about 10-15 mins I noticed; during an instrument scan; that the needle on my oil pressure gauge was about 1/4 inch below the green arc and my oil temperature gauge was 'red lined.' because of the decreasing light; haze; and low altitude; I determined I could no longer wait nor divert to another airport. I called the tower and advised them of my low oil pressure and high temperature; requesting an immediate return for landing. The tower vectored me to intercept the freeway which defines the northern geographic boundary of ZZZ. I followed these instructions and landed without further incident. While I had not explicitly declared an emergency; the tower took the initiative to 'roll the equipment;' which followed me to the parking area of my flight school. Engine temperature reduced to normal during final approach and taxi (low RPM); oil pressure increased to just below the green arc. Inspecting the cowling interior and exterior; fuselage belly; and under the aircraft revealed no oil leaks. The oil level was 6 quarts of 7 maximum; 5 min during preflight. I had flown this airplane the previous day without noticing any pressure or temperature anomalies. The ambient temperature was about 18 degrees C and lower during the flight.

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Original NASA ASRS Text

Title: C172 EXPERIENCES LOW OIL PRESSURE WHILE HOLDING IN VMC CONDITIONS. REQUESTS EXPEDITED HANDLING TO ARPT.

Narrative: TRACON HANDED ME OFF TO THE ZZZ TWR; FROM WHOM I REQUESTED AN SVFR RETURN. THE TWR INSTRUCTED ME TO HOLD IN VMC 5 MI E OF THE ARPT UNTIL CLRED TO CONTINUE TO LAND. I ORBITED AT 2000 FT; 2200 RPM; APPROX 85 KTS; IN A SHALLOW BANK. AFTER ABOUT 10-15 MINS I NOTICED; DURING AN INST SCAN; THAT THE NEEDLE ON MY OIL PRESSURE GAUGE WAS ABOUT 1/4 INCH BELOW THE GREEN ARC AND MY OIL TEMP GAUGE WAS 'RED LINED.' BECAUSE OF THE DECREASING LIGHT; HAZE; AND LOW ALT; I DETERMINED I COULD NO LONGER WAIT NOR DIVERT TO ANOTHER ARPT. I CALLED THE TWR AND ADVISED THEM OF MY LOW OIL PRESSURE AND HIGH TEMP; REQUESTING AN IMMEDIATE RETURN FOR LNDG. THE TWR VECTORED ME TO INTERCEPT THE FREEWAY WHICH DEFINES THE NORTHERN GEOGRAPHIC BOUNDARY OF ZZZ. I FOLLOWED THESE INSTRUCTIONS AND LANDED WITHOUT FURTHER INCIDENT. WHILE I HAD NOT EXPLICITLY DECLARED AN EMER; THE TWR TOOK THE INITIATIVE TO 'ROLL THE EQUIP;' WHICH FOLLOWED ME TO THE PARKING AREA OF MY FLT SCHOOL. ENG TEMP REDUCED TO NORMAL DURING FINAL APCH AND TAXI (LOW RPM); OIL PRESSURE INCREASED TO JUST BELOW THE GREEN ARC. INSPECTING THE COWLING INTERIOR AND EXTERIOR; FUSELAGE BELLY; AND UNDER THE ACFT REVEALED NO OIL LEAKS. THE OIL LEVEL WAS 6 QUARTS OF 7 MAX; 5 MIN DURING PREFLT. I HAD FLOWN THIS AIRPLANE THE PREVIOUS DAY WITHOUT NOTICING ANY PRESSURE OR TEMP ANOMALIES. THE AMBIENT TEMP WAS ABOUT 18 DEGS C AND LOWER DURING THE FLT.

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.