Narrative:

While holding short of runway 23L, I made a 'prepare the cabin' PA and told the passenger we should be airborne in the next 3-4 mins. We were then cleared position and hold. We pulled into position and one of the flight attendants called and said a passenger had just got up to go to the lav. I made a PA and said will all passenger please return to their seats immediately -- we are cleared for takeoff. The tower then cleared us for takeoff. Copilot responded unable due to a passenger standing. Tower canceled our takeoff clearance and told us to clear the runway immediately. The flight attendant called and said passenger was seated. We cleared the runway. Tower said they would work on a new slot time of XA44. I made a PA and said we missed our slot time, but tower is working on another slot time of XA44. Please observe the seat belt sign because I cannot move the aircraft unless everyone is seated. Upon deplaning in ord, the passenger approached me and said that he never knew he could not get up and that I had embarrassed him with my passenger.

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Original NASA ASRS Text

Title: TKOF DELAYED BY PAX IN LAVATORY.

Narrative: WHILE HOLDING SHORT OF RWY 23L, I MADE A 'PREPARE THE CABIN' PA AND TOLD THE PAX WE SHOULD BE AIRBORNE IN THE NEXT 3-4 MINS. WE WERE THEN CLRED POS AND HOLD. WE PULLED INTO POS AND ONE OF THE FLT ATTENDANTS CALLED AND SAID A PAX HAD JUST GOT UP TO GO TO THE LAV. I MADE A PA AND SAID WILL ALL PAX PLEASE RETURN TO THEIR SEATS IMMEDIATELY -- WE ARE CLRED FOR TKOF. THE TWR THEN CLRED US FOR TKOF. COPLT RESPONDED UNABLE DUE TO A PAX STANDING. TWR CANCELED OUR TKOF CLRNC AND TOLD US TO CLR THE RWY IMMEDIATELY. THE FLT ATTENDANT CALLED AND SAID PAX WAS SEATED. WE CLRED THE RWY. TWR SAID THEY WOULD WORK ON A NEW SLOT TIME OF XA44. I MADE A PA AND SAID WE MISSED OUR SLOT TIME, BUT TWR IS WORKING ON ANOTHER SLOT TIME OF XA44. PLEASE OBSERVE THE SEAT BELT SIGN BECAUSE I CANNOT MOVE THE ACFT UNLESS EVERYONE IS SEATED. UPON DEPLANING IN ORD, THE PAX APCHED ME AND SAID THAT HE NEVER KNEW HE COULD NOT GET UP AND THAT I HAD EMBARRASSED HIM WITH MY PAX.

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.