Narrative:

On taxi for departure, first officer made PA 'flight attendants be seated for takeoff.' upon waiting for a response, tower called and said 'air carrier X hold for departure, awaiting IFR release.' first officer responded and we both thought we heard the flight attendants 'ding' us and say they were seated. Meanwhile the tower called again and said 'it just popped up, air carrier X you're cleared for takeoff.' upon passing 12000 ft the 'C' flight attendant called and said 'just so you know, we were still checking passenger seatbelts and we were standing at the start of the takeoff and had to grab the nearest seat.' taxi time was 11 mins.

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Original NASA ASRS Text

Title: A B737 FLT CREW THOUGHT THAT THEY RECEIVED THE CALL FROM THE CABIN ATTENDANTS THAT THEY WERE SEATED. THEY WERE NOT AND THE FLT TOOK OFF WITH THE CABIN ATTENDANTS STANDING.

Narrative: ON TAXI FOR DEP, FO MADE PA 'FLT ATTENDANTS BE SEATED FOR TKOF.' UPON WAITING FOR A RESPONSE, TWR CALLED AND SAID 'ACR X HOLD FOR DEP, AWAITING IFR RELEASE.' FO RESPONDED AND WE BOTH THOUGHT WE HEARD THE FLT ATTENDANTS 'DING' US AND SAY THEY WERE SEATED. MEANWHILE THE TWR CALLED AGAIN AND SAID 'IT JUST POPPED UP, ACR X YOU'RE CLRED FOR TKOF.' UPON PASSING 12000 FT THE 'C' FLT ATTENDANT CALLED AND SAID 'JUST SO YOU KNOW, WE WERE STILL CHKING PAX SEATBELTS AND WE WERE STANDING AT THE START OF THE TKOF AND HAD TO GRAB THE NEAREST SEAT.' TAXI TIME WAS 11 MINS.

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.