Narrative:

Approximately 20-25 mins after takeoff, the first flight attendant notified me that there was an additional passenger on board the aircraft. The passenger, who stated that he had been ill prior to takeoff, had gone into the aft lavatory (left it unlocked, showing unoccupied) during final boarding and had just now come out. He was checked for proper identify, boarding pass, luggage check stubs and verified as a legal/scheduled passenger. All available seats were filled prior to departure, therefore, we now had 1 more passenger than we had seats. We looked at the best options for determining which type of passenger who would be best suited to situation in the flight attendant jump seat for our landing at ord and a passenger was selected. I notified dispatch of the problem and our plans -- they concurred subsequent landing was non eventful. Callback conversation with reporter revealed the following information: the reporter stated that the man was in the unlatched lavatory for taxi and takeoff, and didn't come out until the plane had reached FL200.

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Original NASA ASRS Text

Title: PLT RPT. PAX IN UNLOCKED LAVATORY FOR BOARDING, TAXI AND TKOF. AGENT UNKNOWINGLY FILLED ALL SEATS, LEAVING NO SEAT FOR PAX. PAX RODE ON JUMP SEAT.

Narrative: APPROX 20-25 MINS AFTER TKOF, THE FIRST FLT ATTENDANT NOTIFIED ME THAT THERE WAS AN ADDITIONAL PAX ON BOARD THE ACFT. THE PAX, WHO STATED THAT HE HAD BEEN ILL PRIOR TO TKOF, HAD GONE INTO THE AFT LAVATORY (LEFT IT UNLOCKED, SHOWING UNOCCUPIED) DURING FINAL BOARDING AND HAD JUST NOW COME OUT. HE WAS CHKED FOR PROPER IDENT, BOARDING PASS, LUGGAGE CHK STUBS AND VERIFIED AS A LEGAL/SCHEDULED PAX. ALL AVAILABLE SEATS WERE FILLED PRIOR TO DEP, THEREFORE, WE NOW HAD 1 MORE PAX THAN WE HAD SEATS. WE LOOKED AT THE BEST OPTIONS FOR DETERMINING WHICH TYPE OF PAX WHO WOULD BE BEST SUITED TO SIT IN THE FLT ATTENDANT JUMP SEAT FOR OUR LNDG AT ORD AND A PAX WAS SELECTED. I NOTIFIED DISPATCH OF THE PROB AND OUR PLANS -- THEY CONCURRED SUBSEQUENT LNDG WAS NON EVENTFUL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT THE MAN WAS IN THE UNLATCHED LAVATORY FOR TAXI AND TKOF, AND DIDN'T COME OUT UNTIL THE PLANE HAD REACHED FL200.

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.