Narrative:

Tower cleared us into position and hold on runway 34R at intersection quebec. My last memory of subsequent conflicting aircraft (brasilia) was its holding short of runway 34L for landing traffic. My attention prior to position and hold clearance from tower was reminding first officer to reprogram FMC for runway 34R at quebec intersection (as we had anticipated and input at gate a departure on runway 34L), monitoring his correct input, calling for takeoff checklist 'below the line' while taxiing into position after having received clearance to do so. While taxiing into position and hold tower cleared us for takeoff -- 'no delay, please, landing traffic on a 2 1/2 mi final' -- we completed the checklist and began the takeoff roll. Takeoff roll and rotation was normal, as was climb out to initial flap retraction altitude, when, all of a sudden, an RA began commanding us to climb. When clear of conflict first officer queried the tower as to the reason (if known) for the RA (I was thinking it was traffic in the west downwind pattern at boeing field). Tower's remark was 'the aircraft that had just departed on runway 34L' (the brasilia, although we couldn't see it, we thought). This led us to begin the process of wondering whether in fact we were cleared for takeoff at all. Since the tower, we thought, would never put us in such a position in the first place, would they? Debating the issue back and forth between us for the next hour we were both convinced we did receive takeoff clearance since I verbalized the clearance out loud (as is my customary manner) and the first officer read back the clearance to the tower. We did not receive any subsequent request from the tower, departure, or center to call them on reaching destination.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN ACR FLC FLYING B737 FROM SEA RECEIVED A TCASII RA AFTER TKOF FROM AN ACFT DEPARTING A PARALLEL RWY.

Narrative: TWR CLRED US INTO POS AND HOLD ON RWY 34R AT INTXN QUEBEC. MY LAST MEMORY OF SUBSEQUENT CONFLICTING ACFT (BRASILIA) WAS ITS HOLDING SHORT OF RWY 34L FOR LNDG TFC. MY ATTN PRIOR TO POS AND HOLD CLRNC FROM TWR WAS REMINDING FO TO REPROGRAM FMC FOR RWY 34R AT QUEBEC INTXN (AS WE HAD ANTICIPATED AND INPUT AT GATE A DEP ON RWY 34L), MONITORING HIS CORRECT INPUT, CALLING FOR TKOF CHKLIST 'BELOW THE LINE' WHILE TAXIING INTO POS AFTER HAVING RECEIVED CLRNC TO DO SO. WHILE TAXIING INTO POS AND HOLD TWR CLRED US FOR TKOF -- 'NO DELAY, PLEASE, LNDG TFC ON A 2 1/2 MI FINAL' -- WE COMPLETED THE CHKLIST AND BEGAN THE TKOF ROLL. TKOF ROLL AND ROTATION WAS NORMAL, AS WAS CLBOUT TO INITIAL FLAP RETRACTION ALT, WHEN, ALL OF A SUDDEN, AN RA BEGAN COMMANDING US TO CLB. WHEN CLR OF CONFLICT FO QUERIED THE TWR AS TO THE REASON (IF KNOWN) FOR THE RA (I WAS THINKING IT WAS TFC IN THE W DOWNWIND PATTERN AT BOEING FIELD). TWR'S REMARK WAS 'THE ACFT THAT HAD JUST DEPARTED ON RWY 34L' (THE BRASILIA, ALTHOUGH WE COULDN'T SEE IT, WE THOUGHT). THIS LED US TO BEGIN THE PROCESS OF WONDERING WHETHER IN FACT WE WERE CLRED FOR TKOF AT ALL. SINCE THE TWR, WE THOUGHT, WOULD NEVER PUT US IN SUCH A POS IN THE FIRST PLACE, WOULD THEY? DEBATING THE ISSUE BACK AND FORTH BTWN US FOR THE NEXT HR WE WERE BOTH CONVINCED WE DID RECEIVE TKOF CLRNC SINCE I VERBALIZED THE CLRNC OUT LOUD (AS IS MY CUSTOMARY MANNER) AND THE FO READ BACK THE CLRNC TO THE TWR. WE DID NOT RECEIVE ANY SUBSEQUENT REQUEST FROM THE TWR, DEP, OR CTR TO CALL THEM ON REACHING DEST.

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.