Narrative:

I was cleared to land on runway 16R by manassas tower. I was #2 for landing and #1 had just landed. While on final, aircraft flew perpendicular underneath my aircraft at about 100 ft below me. She then turned right until she was aligned with runway 16R, right underneath me. I asked the tower if they knew a low wing was under me. I executed a go around and the tower asked the low wing if she realized she cut me off. She said 'sorry, I overshot.' I don't believe she ever saw my aircraft and probably still doesn't know how close she was to me. I think the only thing on her mind was she overshot the runway before turning final.

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Original NASA ASRS Text

Title: A C172 SINGLE PLT WAS CLRED TO LAND ON HEF'S RWY 16R WHEN ANOTHER PLT OVERSHOT FINAL FOR RWY 16L CAUSING AN NMAC.

Narrative: I WAS CLRED TO LAND ON RWY 16R BY MANASSAS TWR. I WAS #2 FOR LNDG AND #1 HAD JUST LANDED. WHILE ON FINAL, ACFT FLEW PERPENDICULAR UNDERNEATH MY ACFT AT ABOUT 100 FT BELOW ME. SHE THEN TURNED R UNTIL SHE WAS ALIGNED WITH RWY 16R, RIGHT UNDERNEATH ME. I ASKED THE TWR IF THEY KNEW A LOW WING WAS UNDER ME. I EXECUTED A GAR AND THE TWR ASKED THE LOW WING IF SHE REALIZED SHE CUT ME OFF. SHE SAID 'SORRY, I OVERSHOT.' I DON'T BELIEVE SHE EVER SAW MY ACFT AND PROBABLY STILL DOESN'T KNOW HOW CLOSE SHE WAS TO ME. I THINK THE ONLY THING ON HER MIND WAS SHE OVERSHOT THE RWY BEFORE TURNING FINAL.

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.