Narrative:

Position and hold runway 24 lax, behind B757. Was cleared for takeoff 1 min 10 seconds after B757 was cleared for takeoff. I asked first officer to tell tower that we would need 20 more seconds, which she did. Tower replied that B757 was more than 5 mi ahead. I replied that B757 was 3 mi ahead as indicated by TCASII display. First officer then responded to tower that we were cleared for takeoff as I started the takeoff roll which occurred uneventfully. On climb out, tower instructed us to call them on the phone when we landed. Takeoff clearance was never canceled and we complied with takeoff clearance in a timely manner (within 20 seconds).

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Original NASA ASRS Text

Title: AFTER RECEIVING CLRNC FOR TKOF, AN A320 CAPT DISAGREED WITH LAX TWR REGARDING THE TIME AND DISTANCE OF A PREVIOUSLY DEPARTED B757.

Narrative: POS AND HOLD RWY 24 LAX, BEHIND B757. WAS CLRED FOR TKOF 1 MIN 10 SECONDS AFTER B757 WAS CLRED FOR TKOF. I ASKED FO TO TELL TWR THAT WE WOULD NEED 20 MORE SECONDS, WHICH SHE DID. TWR REPLIED THAT B757 WAS MORE THAN 5 MI AHEAD. I REPLIED THAT B757 WAS 3 MI AHEAD AS INDICATED BY TCASII DISPLAY. FO THEN RESPONDED TO TWR THAT WE WERE CLRED FOR TKOF AS I STARTED THE TKOF ROLL WHICH OCCURRED UNEVENTFULLY. ON CLBOUT, TWR INSTRUCTED US TO CALL THEM ON THE PHONE WHEN WE LANDED. TKOF CLRNC WAS NEVER CANCELED AND WE COMPLIED WITH TKOF CLRNC IN A TIMELY MANNER (WITHIN 20 SECONDS).

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.