Narrative:

We were on a night expressway visual approach to runway 31. I was flying the aircraft. After a landing by a small single-engine aircraft, we were cleared to land. The small aircraft was observed taxiing off and clear of the runway. Just after our touchdown, my copilot observed the small aircraft reentering the left side of the runway. He simultaneously called this out and initiated a left wing up and right rudder input. I saw the small aircraft pass off our left side. He appeared to be parallel to the runway and heading in the direction of landing traffic. I continued the roll out using normal procedures. Radio xmissions revealed the small aircraft was unfamiliar with the airport.

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Original NASA ASRS Text

Title: LGT ON ROLLOUT AT LGA NARROWLY MISSED AN SMA THAT APPEARED TO BE REENTERING THE RWY 31 AFTER CLEARING AFTER LNDG.

Narrative: WE WERE ON A NIGHT EXPRESSWAY VISUAL APCH TO RWY 31. I WAS FLYING THE ACFT. AFTER A LNDG BY A SMALL SINGLE-ENGINE ACFT, WE WERE CLRED TO LAND. THE SMALL ACFT WAS OBSERVED TAXIING OFF AND CLEAR OF THE RWY. JUST AFTER OUR TOUCHDOWN, MY COPLT OBSERVED THE SMALL ACFT REENTERING THE LEFT SIDE OF THE RWY. HE SIMULTANEOUSLY CALLED THIS OUT AND INITIATED A LEFT WING UP AND RIGHT RUDDER INPUT. I SAW THE SMALL ACFT PASS OFF OUR LEFT SIDE. HE APPEARED TO BE PARALLEL TO THE RWY AND HDG IN THE DIRECTION OF LNDG TFC. I CONTINUED THE ROLL OUT USING NORMAL PROCS. RADIO XMISSIONS REVEALED THE SMALL ACFT WAS UNFAMILIAR WITH THE ARPT.

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