Narrative:

After arrival at our destination I was informed by the ramp personnel that 'part of the aircraft is missing.' inspection revealed that the APU access door had apparently been lost during flight. When questioned the aft F/a said she thought she heard a 'thump' a few mins after takeoff. Further investigation revealed that the APU access door on the other side of the aircraft had only 1 of the 6 camlock fasteners completely properly latched. No abnormal indications were noted in the cockpit during the entire flight. The chain of events started when our crew had to deadhead to another base for our first flight. We arrived only 30 mins before our scheduled departure as the aircraft we were to fly was being towed to the gate from the hangar after routine overnight maintenance. Among the items performed by maintenance personnel was an APU service check, which requires the APU access doors to be opened to check the APU oil quantity. I performed the interior preflight and I assigned the first officer to perform our exterior walkaround inspection. Apparently the APU access doors were not properly latched closed after the service check and the first officer did not note any open fasteners during his preflight inspection. Even though the fasteners are flush with the skin of the aircraft, they must also be rotated 90 degrees to lock them into place. Apparently after takeoff, while over the ocean (on the loop departure from lax) the door opened and separated from the aircraft. A contributing cause was the short preflight time available and the ever present pressure to make an on time departure. This may have led either the maintenance crew or the first officer to be rushed and fail to notice the improperly latched APU access door.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR MLG LOST APU ACCESS DOOR AFTER TKOF FROM LAX. PROBLEM NOT DISCOVERED UNTIL POSTFLT INSPECTION AT DESTINATION.

Narrative: AFTER ARR AT OUR DEST I WAS INFORMED BY THE RAMP PERSONNEL THAT 'PART OF THE ACFT IS MISSING.' INSPECTION REVEALED THAT THE APU ACCESS DOOR HAD APPARENTLY BEEN LOST DURING FLT. WHEN QUESTIONED THE AFT F/A SAID SHE THOUGHT SHE HEARD A 'THUMP' A FEW MINS AFTER TKOF. FURTHER INVESTIGATION REVEALED THAT THE APU ACCESS DOOR ON THE OTHER SIDE OF THE ACFT HAD ONLY 1 OF THE 6 CAMLOCK FASTENERS COMPLETELY PROPERLY LATCHED. NO ABNORMAL INDICATIONS WERE NOTED IN THE COCKPIT DURING THE ENTIRE FLT. THE CHAIN OF EVENTS STARTED WHEN OUR CREW HAD TO DEADHEAD TO ANOTHER BASE FOR OUR FIRST FLT. WE ARRIVED ONLY 30 MINS BEFORE OUR SCHEDULED DEP AS THE ACFT WE WERE TO FLY WAS BEING TOWED TO THE GATE FROM THE HANGAR AFTER ROUTINE OVERNIGHT MAINT. AMONG THE ITEMS PERFORMED BY MAINT PERSONNEL WAS AN APU SERVICE CHK, WHICH REQUIRES THE APU ACCESS DOORS TO BE OPENED TO CHK THE APU OIL QUANTITY. I PERFORMED THE INTERIOR PREFLT AND I ASSIGNED THE F/O TO PERFORM OUR EXTERIOR WALKAROUND INSPECTION. APPARENTLY THE APU ACCESS DOORS WERE NOT PROPERLY LATCHED CLOSED AFTER THE SVC CHK AND THE F/O DID NOT NOTE ANY OPEN FASTENERS DURING HIS PREFLT INSPECTION. EVEN THOUGH THE FASTENERS ARE FLUSH WITH THE SKIN OF THE ACFT, THEY MUST ALSO BE ROTATED 90 DEGS TO LOCK THEM INTO PLACE. APPARENTLY AFTER TKOF, WHILE OVER THE OCEAN (ON THE LOOP DEP FROM LAX) THE DOOR OPENED AND SEPARATED FROM THE ACFT. A CONTRIBUTING CAUSE WAS THE SHORT PREFLT TIME AVAILABLE AND THE EVER PRESENT PRESSURE TO MAKE AN ON TIME DEP. THIS MAY HAVE LED EITHER THE MAINT CREW OR THE F/O TO BE RUSHED AND FAIL TO NOTICE THE IMPROPERLY LATCHED APU ACCESS DOOR.

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.