Narrative:

Our aircraft was loaded by ground personnel. In hpn we received our count form which showed a full load of 19 passenger (18 + 1 non-rev). We completed our paperwork, started up and taxied out. Twice before departure we looked back the aisle to make sure it was clear. On landing at iad we were told that we had 20 passenger instead of 19. I assume that this passenger was sitting on someone's lap during takeoff as he was not visible to us (the crew). Our company procedure is that an agent walks up the aisle after boarding thus confirming the count and giving the count form to the pilots in front. This procedure was not followed by ground personnel at hpn. I believe that had this procedure been followed this event would not have occurred. It is obvious that the passenger involved wanted to make this flight. It is much too easy for a passenger to stay out of sight of the flight crew. Therefore our procedure should be followed by ground personnel.

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Original NASA ASRS Text

Title: LTT DEPARTS STATION WITH ONE TOO MANY PASSENGERS FOR ACFT. LOAD MANIFEST INDICATES A NORMAL FULL LOAD. NO HEAD COUNT PERFORMED BY STATION OR GATE AGENT AS PER COMPANY PROC.

Narrative: OUR ACFT WAS LOADED BY GND PERSONNEL. IN HPN WE RECEIVED OUR COUNT FORM WHICH SHOWED A FULL LOAD OF 19 PAX (18 + 1 NON-REV). WE COMPLETED OUR PAPERWORK, STARTED UP AND TAXIED OUT. TWICE BEFORE DEP WE LOOKED BACK THE AISLE TO MAKE SURE IT WAS CLEAR. ON LNDG AT IAD WE WERE TOLD THAT WE HAD 20 PAX INSTEAD OF 19. I ASSUME THAT THIS PAX WAS SITTING ON SOMEONE'S LAP DURING TKOF AS HE WAS NOT VISIBLE TO US (THE CREW). OUR COMPANY PROC IS THAT AN AGENT WALKS UP THE AISLE AFTER BOARDING THUS CONFIRMING THE COUNT AND GIVING THE COUNT FORM TO THE PLTS IN FRONT. THIS PROC WAS NOT FOLLOWED BY GND PERSONNEL AT HPN. I BELIEVE THAT HAD THIS PROC BEEN FOLLOWED THIS EVENT WOULD NOT HAVE OCCURRED. IT IS OBVIOUS THAT THE PAX INVOLVED WANTED TO MAKE THIS FLT. IT IS MUCH TOO EASY FOR A PAX TO STAY OUT OF SIGHT OF THE FLT CREW. THEREFORE OUR PROC SHOULD BE FOLLOWED BY GND PERSONNEL.

Data retrieved from NASA's ASRS site as of August 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.