Narrative:

While flying a scheduled flight for air carrier X to ZZZZ; a panel departed from the aircraft en route to ZZZZ. The flight was normal from takeoff through cruise; the only abnormal event was 5 knot overspd in the clean configuration in VNAV while on descent into ZZZZ. Approach and landing were all normal. We did not know we lost a panel until at layover hotel when we ran into the flight attendants and pilots who were supposed to be flying the plane back. They said a panel had come off during flight; and the aircraft would be fixed on the next day and flown back. As a flight crew we noticed nothing wrong with the handling of the aircraft to indicate any sort of panel loss or abnormal condition with the airplane in any phase of flight.callback conversation with reporter revealed the following information: the reporter stated the panel that departed the aircraft was the fairing between the inboard flap jackscrew and the lower fuselage; adding this has happened several times in the -800 fleet since delivery. The manufacturer has ordered corrective fixes but may not have completely addressed the problem. The fairing was discovered shortly after the incident was reported. The reporter indicated the subject panel was normally identified as the 'elephant ear.'

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Original NASA ASRS Text

Title: A B737-800 HAD THE LEFT INBOARD FLAP INBOARD SEAL PLATE DEPART THE ACFT. CREW UNAWARE OF SEAL DEPARTURE AS FLT WAS NORMAL. DISCOVERED BY OTHER PERSONNEL AFTER ARR.

Narrative: WHILE FLYING A SCHEDULED FLIGHT FOR ACR X TO ZZZZ; A PANEL DEPARTED FROM THE AIRCRAFT ENRTE TO ZZZZ. THE FLIGHT WAS NORMAL FROM TAKEOFF THROUGH CRUISE; THE ONLY ABNORMAL EVENT WAS 5 KNOT OVERSPD IN THE CLEAN CONFIGURATION IN VNAV WHILE ON DESCENT INTO ZZZZ. APPROACH AND LANDING WERE ALL NORMAL. WE DID NOT KNOW WE LOST A PANEL UNTIL AT LAYOVER HOTEL WHEN WE RAN INTO THE FLIGHT ATTENDANTS AND PILOTS WHO WERE SUPPOSED TO BE FLYING THE PLANE BACK. THEY SAID A PANEL HAD COME OFF DURING FLIGHT; AND THE AIRCRAFT WOULD BE FIXED ON THE NEXT DAY AND FLOWN BACK. AS A FLIGHT CREW WE NOTICED NOTHING WRONG WITH THE HANDLING OF THE AIRCRAFT TO INDICATE ANY SORT OF PANEL LOSS OR ABNORMAL CONDITION WITH THE AIRPLANE IN ANY PHASE OF FLIGHT.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE PANEL THAT DEPARTED THE ACFT WAS THE FAIRING BETWEEN THE INBOARD FLAP JACKSCREW AND THE LOWER FUSELAGE; ADDING THIS HAS HAPPENED SEVERAL TIMES IN THE -800 FLEET SINCE DELIVERY. THE MANUFACTURER HAS ORDERED CORRECTIVE FIXES BUT MAY NOT HAVE COMPLETELY ADDRESSED THE PROB. THE FAIRING WAS DISCOVERED SHORTLY AFTER THE INCIDENT WAS RPTED. THE RPTR INDICATED THE SUBJECT PANEL WAS NORMALLY IDENTIFIED AS THE 'ELEPHANT EAR.'

Data retrieved from NASA's ASRS site as of January 2009 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.