Narrative:

Taxi for takeoff in restr visibility at lga for departure on runway 4. Ground control and tower were combined on 1 frequency. An air carrier X aircraft was waiting for takeoff. Just after beginning our taxi from gate, we heard what sounded like a snow plow ask if he could have the runway back after air carrier X departed. Tower said yes. We called the tower to remind them that we were taxiing out so they would keep the runway open long enough for us to depart. The first officer then contacted dispatch to update them on field conditions. I heard a vehicle request clearance to cross the runway, which was granted. Tower told us to call when #1 for takeoff. We did -- about 3-5 mins after I heard the vehicle ask for crossing clearance. We then got clearance to taxi into position and hold to call when ready. We called ready and were cleared for takeoff. Just after rotation we saw vehicles crossing our runway at about taxiway P or taxiway G. We flew over them at 50-75 ft (ceiling 100 ft). I reported this to tower. The controller asked the vehicles what they were doing on his runway. I think either the controller assumed they had already crossed (they should have been clear several mins earlier) and I also think the snow plows thought air carrier X was the only departure and they could have the runway back. Apparently, only 1 car had an ATC radio and the other plows and vehicle followed him, or they just crossed without clearance. They should have heard our takeoff clearance. They knew we were taxiing because they had to give way to us at taxiway east.

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Original NASA ASRS Text

Title: A320 CREW SHORTLY AFTER ROTATION, IN A LOW VISIBILITY CONDITION, SAW VEHICLES ON THE RWY.

Narrative: TAXI FOR TKOF IN RESTR VISIBILITY AT LGA FOR DEP ON RWY 4. GND CTL AND TWR WERE COMBINED ON 1 FREQ. AN ACR X ACFT WAS WAITING FOR TKOF. JUST AFTER BEGINNING OUR TAXI FROM GATE, WE HEARD WHAT SOUNDED LIKE A SNOW PLOW ASK IF HE COULD HAVE THE RWY BACK AFTER ACR X DEPARTED. TWR SAID YES. WE CALLED THE TWR TO REMIND THEM THAT WE WERE TAXIING OUT SO THEY WOULD KEEP THE RWY OPEN LONG ENOUGH FOR US TO DEPART. THE FO THEN CONTACTED DISPATCH TO UPDATE THEM ON FIELD CONDITIONS. I HEARD A VEHICLE REQUEST CLRNC TO CROSS THE RWY, WHICH WAS GRANTED. TWR TOLD US TO CALL WHEN #1 FOR TKOF. WE DID -- ABOUT 3-5 MINS AFTER I HEARD THE VEHICLE ASK FOR XING CLRNC. WE THEN GOT CLRNC TO TAXI INTO POS AND HOLD TO CALL WHEN READY. WE CALLED READY AND WERE CLRED FOR TKOF. JUST AFTER ROTATION WE SAW VEHICLES XING OUR RWY AT ABOUT TXWY P OR TXWY G. WE FLEW OVER THEM AT 50-75 FT (CEILING 100 FT). I RPTED THIS TO TWR. THE CTLR ASKED THE VEHICLES WHAT THEY WERE DOING ON HIS RWY. I THINK EITHER THE CTLR ASSUMED THEY HAD ALREADY CROSSED (THEY SHOULD HAVE BEEN CLR SEVERAL MINS EARLIER) AND I ALSO THINK THE SNOW PLOWS THOUGHT ACR X WAS THE ONLY DEP AND THEY COULD HAVE THE RWY BACK. APPARENTLY, ONLY 1 CAR HAD AN ATC RADIO AND THE OTHER PLOWS AND VEHICLE FOLLOWED HIM, OR THEY JUST CROSSED WITHOUT CLRNC. THEY SHOULD HAVE HEARD OUR TKOF CLRNC. THEY KNEW WE WERE TAXIING BECAUSE THEY HAD TO GIVE WAY TO US AT TXWY E.

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.