Narrative:

Flight from ZZZ to psp. After deplaning aircraft, I asked flight attendant #2 to get the unaccompanied minor and she said everyone was gone. I thought he might have left with the family he was sitting with so I told the crew I was going down to baggage claim to look for him. After searching the baggage area and not finding him, I saw the family he was sitting with and asked the little girl sitting next to him if the unaccompanied minor had deplaned with her family and she said, 'no, he is sleeping.' I ran back to security and saw the grandparents and realized the boy was still on the airplane. Because security was closed, I had to run around the entire parameter of the airport to get back on the airplane. By the time I got there, a police officer was coming down the jetway and we found the boy under a pile of blankets, sleeping. The aircraft was open and the lights were still on. On boarding the unaccompanied minor, I did brief him on not to leave the airplane without the flight attendants. Supplemental information from acn 546983: I began helping one of the last passenger (a woman with her child and a car seat) to carry her bags to the aircraft door after checking the lavatories. After handing the woman her bags, I asked the load flight attendant where the unaccompanied minor was. She then asked the 'C' flight attendant if he was still in the cabin. She said no. I had visually checked the cabin and overhead bins as I carried the woman's bags up and had not seen anything unusual.

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Original NASA ASRS Text

Title: A B737-500 FLT ATTENDANT FORGOT THAT AN UNACCOMPANIED MINOR WAS ABOARD THE ACFT. THEY LEFT THE UNACCOMPANIED MINOR ABOARD AND DEPLANED THE ACFT.

Narrative: FLT FROM ZZZ TO PSP. AFTER DEPLANING ACFT, I ASKED FLT ATTENDANT #2 TO GET THE UNACCOMPANIED MINOR AND SHE SAID EVERYONE WAS GONE. I THOUGHT HE MIGHT HAVE LEFT WITH THE FAMILY HE WAS SITTING WITH SO I TOLD THE CREW I WAS GOING DOWN TO BAGGAGE CLAIM TO LOOK FOR HIM. AFTER SEARCHING THE BAGGAGE AREA AND NOT FINDING HIM, I SAW THE FAMILY HE WAS SITTING WITH AND ASKED THE LITTLE GIRL SITTING NEXT TO HIM IF THE UNACCOMPANIED MINOR HAD DEPLANED WITH HER FAMILY AND SHE SAID, 'NO, HE IS SLEEPING.' I RAN BACK TO SECURITY AND SAW THE GRANDPARENTS AND REALIZED THE BOY WAS STILL ON THE AIRPLANE. BECAUSE SECURITY WAS CLOSED, I HAD TO RUN AROUND THE ENTIRE PARAMETER OF THE ARPT TO GET BACK ON THE AIRPLANE. BY THE TIME I GOT THERE, A POLICE OFFICER WAS COMING DOWN THE JETWAY AND WE FOUND THE BOY UNDER A PILE OF BLANKETS, SLEEPING. THE ACFT WAS OPEN AND THE LIGHTS WERE STILL ON. ON BOARDING THE UNACCOMPANIED MINOR, I DID BRIEF HIM ON NOT TO LEAVE THE AIRPLANE WITHOUT THE FLT ATTENDANTS. SUPPLEMENTAL INFO FROM ACN 546983: I BEGAN HELPING ONE OF THE LAST PAX (A WOMAN WITH HER CHILD AND A CAR SEAT) TO CARRY HER BAGS TO THE ACFT DOOR AFTER CHKING THE LAVATORIES. AFTER HANDING THE WOMAN HER BAGS, I ASKED THE LOAD FLT ATTENDANT WHERE THE UNACCOMPANIED MINOR WAS. SHE THEN ASKED THE 'C' FLT ATTENDANT IF HE WAS STILL IN THE CABIN. SHE SAID NO. I HAD VISUALLY CHKED THE CABIN AND OVERHEAD BINS AS I CARRIED THE WOMAN'S BAGS UP AND HAD NOT SEEN ANYTHING UNUSUAL.

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.