Narrative:

Over wilmington, de, my passenger noticed that it looked like we got hit by a big bird dropping on windshield in front of his seat (left). I glanced over and noticed a yellow smudge at the base of the windshield (small aircraft) about the size of a small fist. I couldn't give it much attention as I was distracted by watching for numerous aircraft in and out of ilg on the 99's pennies-a-pound charity airlift. I was talking to ilg tower who were very busy and abrupt, and I was further continually interrupted by my passenger who was constantly asking typical 'first flight' questions. After we passed ilg with about 9 mi to get to N57, it occurred to me that the yellow spot looked like oil. I checked my gauges, but all was normal. I thought about whether I put the cap on the oil spout after I checked the oil during the miv preflight, and couldn't remember if I closed it. (Something I never did before -- forget to put the cap on. I added a quart at miv.) after looking at the gauges, which were all normal, the fact that I had 9 mi to get to new garden and the fact that the ilg tower was so busy and agitated, I decided to continue to N57. I landed with a direct crosswind, still very turbulent, but the gauges still reading normal. When we got out of the plane, we saw oil all over the left side of the aircraft and the cap off. We lost 1 1/2 quarts of oil. I either forgot to put the cap on, or didn't tighten it securely. I attribute it to the WX forecast, my distracting, curious passenger, and some other mental factor -- that morning I also forgot to screw my car gas cap on (also something I've never forgotten before) and when I got home, I discovered I forgot to put the cover on the outside hot tub! Fortunately, it ended with no problems.

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Original NASA ASRS Text

Title: PLT OF AN SMA SINGLE ENG LAND ACFT L ENG OIL CAP OFF DURING PREFLT AND LOST OIL INFLT.

Narrative: OVER WILMINGTON, DE, MY PAX NOTICED THAT IT LOOKED LIKE WE GOT HIT BY A BIG BIRD DROPPING ON WINDSHIELD IN FRONT OF HIS SEAT (L). I GLANCED OVER AND NOTICED A YELLOW SMUDGE AT THE BASE OF THE WINDSHIELD (SMA) ABOUT THE SIZE OF A SMALL FIST. I COULDN'T GIVE IT MUCH ATTN AS I WAS DISTRACTED BY WATCHING FOR NUMEROUS ACFT IN AND OUT OF ILG ON THE 99'S PENNIES-A-POUND CHARITY AIRLIFT. I WAS TALKING TO ILG TWR WHO WERE VERY BUSY AND ABRUPT, AND I WAS FURTHER CONTINUALLY INTERRUPTED BY MY PAX WHO WAS CONSTANTLY ASKING TYPICAL 'FIRST FLT' QUESTIONS. AFTER WE PASSED ILG WITH ABOUT 9 MI TO GET TO N57, IT OCCURRED TO ME THAT THE YELLOW SPOT LOOKED LIKE OIL. I CHKED MY GAUGES, BUT ALL WAS NORMAL. I THOUGHT ABOUT WHETHER I PUT THE CAP ON THE OIL SPOUT AFTER I CHKED THE OIL DURING THE MIV PREFLT, AND COULDN'T REMEMBER IF I CLOSED IT. (SOMETHING I NEVER DID BEFORE -- FORGET TO PUT THE CAP ON. I ADDED A QUART AT MIV.) AFTER LOOKING AT THE GAUGES, WHICH WERE ALL NORMAL, THE FACT THAT I HAD 9 MI TO GET TO NEW GARDEN AND THE FACT THAT THE ILG TWR WAS SO BUSY AND AGITATED, I DECIDED TO CONTINUE TO N57. I LANDED WITH A DIRECT XWIND, STILL VERY TURBULENT, BUT THE GAUGES STILL READING NORMAL. WHEN WE GOT OUT OF THE PLANE, WE SAW OIL ALL OVER THE L SIDE OF THE ACFT AND THE CAP OFF. WE LOST 1 1/2 QUARTS OF OIL. I EITHER FORGOT TO PUT THE CAP ON, OR DIDN'T TIGHTEN IT SECURELY. I ATTRIBUTE IT TO THE WX FORECAST, MY DISTRACTING, CURIOUS PAX, AND SOME OTHER MENTAL FACTOR -- THAT MORNING I ALSO FORGOT TO SCREW MY CAR GAS CAP ON (ALSO SOMETHING I'VE NEVER FORGOTTEN BEFORE) AND WHEN I GOT HOME, I DISCOVERED I FORGOT TO PUT THE COVER ON THE OUTSIDE HOT TUB! FORTUNATELY, IT ENDED WITH NO PROBS.

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.