Narrative:

I had passenger flight from mvy to teb. My passenger and I departed mvy for teb. We leveled at our VFR altitude of 400-500 ft MSL with radar advisories. An hour later, we began a VFR descent to 2500 ft MSL to remain clear of new york's class B airspace. Upon approaching 3500 ft MSL, we received a class B clearance from new york approach. It was around this time that I noticed a significant amount of oil leaking down the cowling on the left engine. Concurrently, there was a slow, gradual decrease in the left oil pressure. I immediately advised new york approach of our situation and requested a straight-in approach to runway 29 at hpn. They notified the tower and advised us to change our frequency to hpn tower. We received a landing clearance from hpn tower and landed uneventfully. Upon touchdown, I shut down and secured the left engine. I taxied in with power from the right engine. Upon shutdown, the hpn emergency truck arrived. The driver advised me that new york approach or hpn tower had declared an emergency on my behalf.

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Original NASA ASRS Text

Title: PA34 PLT HAS OIL LEAK ON L ENG WHILE ENRTE AND DIVERTS TO HPN.

Narrative: I HAD PAX FLT FROM MVY TO TEB. MY PAX AND I DEPARTED MVY FOR TEB. WE LEVELED AT OUR VFR ALT OF 400-500 FT MSL WITH RADAR ADVISORIES. AN HR LATER, WE BEGAN A VFR DSCNT TO 2500 FT MSL TO REMAIN CLR OF NEW YORK'S CLASS B AIRSPACE. UPON APCHING 3500 FT MSL, WE RECEIVED A CLASS B CLRNC FROM NEW YORK APCH. IT WAS AROUND THIS TIME THAT I NOTICED A SIGNIFICANT AMOUNT OF OIL LEAKING DOWN THE COWLING ON THE L ENG. CONCURRENTLY, THERE WAS A SLOW, GRADUAL DECREASE IN THE L OIL PRESSURE. I IMMEDIATELY ADVISED NEW YORK APCH OF OUR SIT AND REQUESTED A STRAIGHT-IN APCH TO RWY 29 AT HPN. THEY NOTIFIED THE TWR AND ADVISED US TO CHANGE OUR FREQ TO HPN TWR. WE RECEIVED A LNDG CLRNC FROM HPN TWR AND LANDED UNEVENTFULLY. UPON TOUCHDOWN, I SHUT DOWN AND SECURED THE L ENG. I TAXIED IN WITH PWR FROM THE R ENG. UPON SHUTDOWN, THE HPN EMER TRUCK ARRIVED. THE DRIVER ADVISED ME THAT NEW YORK APCH OR HPN TWR HAD DECLARED AN EMER ON MY BEHALF.

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.