Narrative:

Took off for flight from chicago to phoenix with 13 more passenger on board than we thought. Apparently, the agent who boarded the flight reported an incorrect number of passenger to load control who then calculated a lighter than actual takeoff weight. For reasons not entirely clear to me, the agent did not, upon learning of the problem, immediately notify us of the discrepancy. He elected to simply notify the captain to call upon arrival in phoenix. Unfortunately, this led to seemingly erroneous thrust management problems en route and a 'hard' landing in phoenix. Upon discussion with the flight attendants they said, 'didn't you hear that they were paying people to get off the flight?' we obviously did not. During boarding, pilots are typically occupied with checklists, clrncs, etc. I have now flown with 3 different part 121 operations. This is the first that does not require either the agent or flight attendant to notify the cockpit of a final passenger count. This procedure may have helped the pilots to catch the oversight. Loads often 'fall apart' so a reduction in expected passenger load was not by itself cause for concern.

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Original NASA ASRS Text

Title: AN MLG ACR CREW FOUND THAT THEY HAD 13 MORE PAX THAN THE COCKPIT CREW KNEW ABOUT.

Narrative: TOOK OFF FOR FLT FROM CHICAGO TO PHOENIX WITH 13 MORE PAX ON BOARD THAN WE THOUGHT. APPARENTLY, THE AGENT WHO BOARDED THE FLT RPTED AN INCORRECT NUMBER OF PAX TO LOAD CTL WHO THEN CALCULATED A LIGHTER THAN ACTUAL TKOF WEIGHT. FOR REASONS NOT ENTIRELY CLR TO ME, THE AGENT DID NOT, UPON LEARNING OF THE PROBLEM, IMMEDIATELY NOTIFY US OF THE DISCREPANCY. HE ELECTED TO SIMPLY NOTIFY THE CAPT TO CALL UPON ARR IN PHOENIX. UNFORTUNATELY, THIS LED TO SEEMINGLY ERRONEOUS THRUST MGMNT PROBLEMS ENRTE AND A 'HARD' LNDG IN PHOENIX. UPON DISCUSSION WITH THE FLT ATTENDANTS THEY SAID, 'DIDN'T YOU HEAR THAT THEY WERE PAYING PEOPLE TO GET OFF THE FLT?' WE OBVIOUSLY DID NOT. DURING BOARDING, PLTS ARE TYPICALLY OCCUPIED WITH CHKLISTS, CLRNCS, ETC. I HAVE NOW FLOWN WITH 3 DIFFERENT PART 121 OPS. THIS IS THE FIRST THAT DOES NOT REQUIRE EITHER THE AGENT OR FLT ATTENDANT TO NOTIFY THE COCKPIT OF A FINAL PAX COUNT. THIS PROC MAY HAVE HELPED THE PLTS TO CATCH THE OVERSIGHT. LOADS OFTEN 'FALL APART' SO A REDUCTION IN EXPECTED PAX LOAD WAS NOT BY ITSELF CAUSE FOR CONCERN.

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.