Narrative:

We were cleared for takeoff on runway 13 lga, with landing traffic on approach to runway 4. After toga thrust was set and our aircraft was rolling, tower gave us instructions to hold our position. With little time to react, and our aircraft accelerating rapidly toward the runway 4 intersection, the captain decided to continue the takeoff roll. First officer replied 'unable' to the 'hold position' clearance. We passed through the runway intersection well before the landing traffic touched down. After takeoff, we discussed what had happened. We both agreed that if we had tried to stop on the runway (abort), we might have ended up right in the intersection, which would have caused a big problem. Continuing the takeoff was the right thing to do. ATC seems to be trying harder and harder to get more aircraft in and out of these busy airports, and separation distances have decreased. Callback conversation with reporter revealed the following information: the reporter indicated that the other aircraft was a turboprop commuter type aircraft that was estimated to be 3000 ft out on final approach to runway 22. The separation of the aircraft would have been an estimated 5000 ft as the reporter crossed the intersection. The reporter's comment was that there was 'no conflict' and his concern was that to reject the takeoff at the point clearance was canceled would have created one. The terminology used to cancel the clearance was something to the effect of 'new plan air carrier XXX, hold your position.' by this time, the takeoff had already begun, the aircraft was light and acceleration was rapid, which all contributed to the decision that was made to continue.

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Original NASA ASRS Text

Title: TKOF CLRNC GIVEN AND RESCINDED AFTER START OF THE TKOF ROLL DUE TO APCHING TFC ON XING RWY AT LGA, NY. TKOF WAS CONTINUED.

Narrative: WE WERE CLRED FOR TKOF ON RWY 13 LGA, WITH LNDG TFC ON APCH TO RWY 4. AFTER TOGA THRUST WAS SET AND OUR ACFT WAS ROLLING, TWR GAVE US INSTRUCTIONS TO HOLD OUR POS. WITH LITTLE TIME TO REACT, AND OUR ACFT ACCELERATING RAPIDLY TOWARD THE RWY 4 INTXN, THE CAPT DECIDED TO CONTINUE THE TKOF ROLL. FO REPLIED 'UNABLE' TO THE 'HOLD POS' CLRNC. WE PASSED THROUGH THE RWY INTXN WELL BEFORE THE LNDG TFC TOUCHED DOWN. AFTER TKOF, WE DISCUSSED WHAT HAD HAPPENED. WE BOTH AGREED THAT IF WE HAD TRIED TO STOP ON THE RWY (ABORT), WE MIGHT HAVE ENDED UP RIGHT IN THE INTXN, WHICH WOULD HAVE CAUSED A BIG PROB. CONTINUING THE TKOF WAS THE RIGHT THING TO DO. ATC SEEMS TO BE TRYING HARDER AND HARDER TO GET MORE ACFT IN AND OUT OF THESE BUSY ARPTS, AND SEPARATION DISTANCES HAVE DECREASED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR INDICATED THAT THE OTHER ACFT WAS A TURBOPROP COMMUTER TYPE ACFT THAT WAS ESTIMATED TO BE 3000 FT OUT ON FINAL APCH TO RWY 22. THE SEPARATION OF THE ACFT WOULD HAVE BEEN AN ESTIMATED 5000 FT AS THE RPTR CROSSED THE INTXN. THE RPTR'S COMMENT WAS THAT THERE WAS 'NO CONFLICT' AND HIS CONCERN WAS THAT TO REJECT THE TKOF AT THE POINT CLRNC WAS CANCELED WOULD HAVE CREATED ONE. THE TERMINOLOGY USED TO CANCEL THE CLRNC WAS SOMETHING TO THE EFFECT OF 'NEW PLAN ACR XXX, HOLD YOUR POS.' BY THIS TIME, THE TKOF HAD ALREADY BEGUN, THE ACFT WAS LIGHT AND ACCELERATION WAS RAPID, WHICH ALL CONTRIBUTED TO THE DECISION THAT WAS MADE TO CONTINUE.

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.