Narrative:

I am a captain of a 19 seat commuter airplane. The particular airplane I was to fly had only 18 seats available because 1 seat was in need of repair, and was placarded unusable. At my airline, the captain does the entire manifest in the cockpit, after the right engine has been started, in order to expedite the departure. While figuring the manifest, I became involved in a conversation with one of the baggage handlers as to the weight distribution limits in the aft cargo compartments. This exchange was delaying our gate departure. The first officer was busy giving the required safety briefing to the passenger. I did not notice that 19 passenger had been boarded and seated. I quickly completed the manifest and departed the gate. I had completely forgotten that 1 seat was placarded unusable until after the flight had been completed. Evidently, the person who sat in the seat with 'do not occupy' in very large letters found it usable enough. The lessons to be learned from this incident are not new ones to most professional pilots: if I had not been so preoccupied with the aft cargo loading, and if I had not been so preoccupied with the aft cargo loading, and if I had not rushed to complete the manifest in order to stay on schedule, I would have seen that I recorded 19 passenger on the manifest. Also, a contributing factor in this incident was some measure of mental fatigue due to a lack of sufficient sleep from a reduced rest period the previous night.

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Original NASA ASRS Text

Title: COMMUTER ACFT DEPARTS WITH UNUSABLE PAX SEAT OCCUPIED.

Narrative: I AM A CAPT OF A 19 SEAT COMMUTER AIRPLANE. THE PARTICULAR AIRPLANE I WAS TO FLY HAD ONLY 18 SEATS AVAILABLE BECAUSE 1 SEAT WAS IN NEED OF REPAIR, AND WAS PLACARDED UNUSABLE. AT MY AIRLINE, THE CAPT DOES THE ENTIRE MANIFEST IN THE COCKPIT, AFTER THE R ENG HAS BEEN STARTED, IN ORDER TO EXPEDITE THE DEP. WHILE FIGURING THE MANIFEST, I BECAME INVOLVED IN A CONVERSATION WITH ONE OF THE BAGGAGE HANDLERS AS TO THE WT DISTRIBUTION LIMITS IN THE AFT CARGO COMPARTMENTS. THIS EXCHANGE WAS DELAYING OUR GATE DEP. THE FO WAS BUSY GIVING THE REQUIRED SAFETY BRIEFING TO THE PAX. I DID NOT NOTICE THAT 19 PAX HAD BEEN BOARDED AND SEATED. I QUICKLY COMPLETED THE MANIFEST AND DEPARTED THE GATE. I HAD COMPLETELY FORGOTTEN THAT 1 SEAT WAS PLACARDED UNUSABLE UNTIL AFTER THE FLT HAD BEEN COMPLETED. EVIDENTLY, THE PERSON WHO SAT IN THE SEAT WITH 'DO NOT OCCUPY' IN VERY LARGE LETTERS FOUND IT USABLE ENOUGH. THE LESSONS TO BE LEARNED FROM THIS INCIDENT ARE NOT NEW ONES TO MOST PROFESSIONAL PLTS: IF I HAD NOT BEEN SO PREOCCUPIED WITH THE AFT CARGO LOADING, AND IF I HAD NOT BEEN SO PREOCCUPIED WITH THE AFT CARGO LOADING, AND IF I HAD NOT RUSHED TO COMPLETE THE MANIFEST IN ORDER TO STAY ON SCHEDULE, I WOULD HAVE SEEN THAT I RECORDED 19 PAX ON THE MANIFEST. ALSO, A CONTRIBUTING FACTOR IN THIS INCIDENT WAS SOME MEASURE OF MENTAL FATIGUE DUE TO A LACK OF SUFFICIENT SLEEP FROM A REDUCED REST PERIOD THE PREVIOUS NIGHT.

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.