Narrative:

Flight was en route bwi-lax. Everything was routine/normal until flaps were extended on approach. The leading edge devices annunciator on the aft overhead panel indicated normally and the leading edge devices appeared to be extended when visually checked; however, the trailing edge flap position indicator (on the center panel) did not move as the flaps were selected. Captain decided to go around. While being radar vectored, captain called lead flight attendant and told him to visually check the trailing edge flaps. Flight attendant left to do that. Captain then noticed the 'trailing edge flaps position indicator' circuit breaker on P6 panel (behind my seat at shoulder level) was popped -- he reset the circuit breaker and the flap indicator worked fine; lead flight attendant returned and confirmed the trailing edge flaps were extended. Our flight then continued without further incident. This wasn't the first time for me that this type of situation has occurred on the aircraft. In retrospect, I think the following chain of events caused this to happen in this case: for the first 3 1/2 hours or so of the flight I was in my seat with both my seat belt and shoulder harness fastened. I then left the flight deck briefly. (I was careful to hold the shoulder harness straps as they recoiled into the seat back). When I returned, I fastened only the lap belt portion of my seat belt/shoulder harness. Prior to our descent from cruise, I reattached my shoulder harness; however, one belt got twisted as I did. I released the 5 point harness to untwist the one shoulder strap, and tried to hold on to the other 4 belts as I did. The second shoulder harness strap slipped and recoiled into the seat back. This is where I think the shoulder harness buckle flipped over the top of the seat back and hit the 'trailing edge flap position indicator' circuit breaker causing it to pop (later while at the gate I intentionally hit the trailing edge flap position indicator circuit breaker with the shoulder strap buckle to show the captain how this can happen). The circuit breaker again popped out. If the company, or aircraft manufacturer, would install a small plastic cover over the circuit breaker area immediately behind the first officer's seat back, I think it would prevent situations like this from happening again.

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Original NASA ASRS Text

Title: ACR MLG FLC EXPERIENCES LOSS OF TRAILING EDGE FLAP INDICATION DUE TO AN INADVERTENTLY POPPED CIRCUIT BREAKER. THE FLT EXECUTED A GAR WHILE SORTING OUT THE PROBLEM.

Narrative: FLT WAS ENRTE BWI-LAX. EVERYTHING WAS ROUTINE/NORMAL UNTIL FLAPS WERE EXTENDED ON APCH. THE LEADING EDGE DEVICES ANNUNCIATOR ON THE AFT OVERHEAD PANEL INDICATED NORMALLY AND THE LEADING EDGE DEVICES APPEARED TO BE EXTENDED WHEN VISUALLY CHKED; HOWEVER, THE TRAILING EDGE FLAP POS INDICATOR (ON THE CTR PANEL) DID NOT MOVE AS THE FLAPS WERE SELECTED. CAPT DECIDED TO GAR. WHILE BEING RADAR VECTORED, CAPT CALLED LEAD FLT ATTENDANT AND TOLD HIM TO VISUALLY CHK THE TRAILING EDGE FLAPS. FLT ATTENDANT LEFT TO DO THAT. CAPT THEN NOTICED THE 'TRAILING EDGE FLAPS POS INDICATOR' CIRCUIT BREAKER ON P6 PANEL (BEHIND MY SEAT AT SHOULDER LEVEL) WAS POPPED -- HE RESET THE CIRCUIT BREAKER AND THE FLAP INDICATOR WORKED FINE; LEAD FLT ATTENDANT RETURNED AND CONFIRMED THE TRAILING EDGE FLAPS WERE EXTENDED. OUR FLT THEN CONTINUED WITHOUT FURTHER INCIDENT. THIS WASN'T THE FIRST TIME FOR ME THAT THIS TYPE OF SITUATION HAS OCCURRED ON THE ACFT. IN RETROSPECT, I THINK THE FOLLOWING CHAIN OF EVENTS CAUSED THIS TO HAPPEN IN THIS CASE: FOR THE FIRST 3 1/2 HRS OR SO OF THE FLT I WAS IN MY SEAT WITH BOTH MY SEAT BELT AND SHOULDER HARNESS FASTENED. I THEN LEFT THE FLT DECK BRIEFLY. (I WAS CAREFUL TO HOLD THE SHOULDER HARNESS STRAPS AS THEY RECOILED INTO THE SEAT BACK). WHEN I RETURNED, I FASTENED ONLY THE LAP BELT PORTION OF MY SEAT BELT/SHOULDER HARNESS. PRIOR TO OUR DSCNT FROM CRUISE, I REATTACHED MY SHOULDER HARNESS; HOWEVER, ONE BELT GOT TWISTED AS I DID. I RELEASED THE 5 POINT HARNESS TO UNTWIST THE ONE SHOULDER STRAP, AND TRIED TO HOLD ON TO THE OTHER 4 BELTS AS I DID. THE SECOND SHOULDER HARNESS STRAP SLIPPED AND RECOILED INTO THE SEAT BACK. THIS IS WHERE I THINK THE SHOULDER HARNESS BUCKLE FLIPPED OVER THE TOP OF THE SEAT BACK AND HIT THE 'TRAILING EDGE FLAP POS INDICATOR' CIRCUIT BREAKER CAUSING IT TO POP (LATER WHILE AT THE GATE I INTENTIONALLY HIT THE TRAILING EDGE FLAP POS INDICATOR CB WITH THE SHOULDER STRAP BUCKLE TO SHOW THE CAPT HOW THIS CAN HAPPEN). THE CIRCUIT BREAKER AGAIN POPPED OUT. IF THE COMPANY, OR ACFT MANUFACTURER, WOULD INSTALL A SMALL PLASTIC COVER OVER THE CIRCUIT BREAKER AREA IMMEDIATELY BEHIND THE FO'S SEAT BACK, I THINK IT WOULD PREVENT SITUATIONS LIKE THIS FROM HAPPENING AGAIN.

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.