Narrative:

2 capts flying. My leg flying as first officer. Cleared to position and hold. Captain called continue and started taxi onto runway 1L. I continued before takeoff check, which hadn't reached down to the line. As I reached end of check, captain still had aircraft rolling and started moving power levers forward. I took over from there and asked if we were cleared for takeoff. He said yes, 'go, go.' levers went forward and I continued that I had not heard the clearance. On the roll captain noticed an large transport on 28L crossing 1L and said, 'what's the large transport doing there?' tower told large transport to take next exit on his landing roll. Not extremely unusual on a busy day at sfo. No factor as large transport exited before we reached the 28's. After takeoff departure asked us to contact tower (sfo) by phone at the destination. Factors: I, as a new captain (less than 35 hours in aircraft type) and only a few hours in the right seat, not having the checklist memorized, was slow in getting through before takeoff check. This seemed to make the captain nervous. When he said 'go,' I thought I must have missed the clearance to takeoff while finishing the checklist. I believe the captain felt rushed. I feel not taking the active until finished with proper phase of checklist was needed. Also the captain never stopped the aircraft on the runway but continued the roll, which confused me enough to take his word that we were cleared to go, even after questioning him on that.

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Original NASA ASRS Text

Title: UNAUTH TKOF.

Narrative: 2 CAPTS FLYING. MY LEG FLYING AS F/O. CLRED TO POS AND HOLD. CAPT CALLED CONTINUE AND STARTED TAXI ONTO RWY 1L. I CONTINUED BEFORE TKOF CHK, WHICH HADN'T REACHED DOWN TO THE LINE. AS I REACHED END OF CHK, CAPT STILL HAD ACFT ROLLING AND STARTED MOVING PWR LEVERS FORWARD. I TOOK OVER FROM THERE AND ASKED IF WE WERE CLRED FOR TKOF. HE SAID YES, 'GO, GO.' LEVERS WENT FORWARD AND I CONTINUED THAT I HAD NOT HEARD THE CLRNC. ON THE ROLL CAPT NOTICED AN LGT ON 28L XING 1L AND SAID, 'WHAT'S THE LGT DOING THERE?' TWR TOLD LGT TO TAKE NEXT EXIT ON HIS LNDG ROLL. NOT EXTREMELY UNUSUAL ON A BUSY DAY AT SFO. NO FACTOR AS LGT EXITED BEFORE WE REACHED THE 28'S. AFTER TKOF DEP ASKED US TO CONTACT TWR (SFO) BY PHONE AT THE DEST. FACTORS: I, AS A NEW CAPT (LESS THAN 35 HRS IN ACFT TYPE) AND ONLY A FEW HRS IN THE RIGHT SEAT, NOT HAVING THE CHKLIST MEMORIZED, WAS SLOW IN GETTING THROUGH BEFORE TKOF CHK. THIS SEEMED TO MAKE THE CAPT NERVOUS. WHEN HE SAID 'GO,' I THOUGHT I MUST HAVE MISSED THE CLRNC TO TKOF WHILE FINISHING THE CHKLIST. I BELIEVE THE CAPT FELT RUSHED. I FEEL NOT TAKING THE ACTIVE UNTIL FINISHED WITH PROPER PHASE OF CHKLIST WAS NEEDED. ALSO THE CAPT NEVER STOPPED THE ACFT ON THE RWY BUT CONTINUED THE ROLL, WHICH CONFUSED ME ENOUGH TO TAKE HIS WORD THAT WE WERE CLRED TO GO, EVEN AFTER QUESTIONING HIM ON THAT.

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.