Narrative:

We were flying at FL300 in the WX. I was the relief pilot and the copilot (PF) had just left for his break. We got an aural warning and the first thing I noticed was the leading edge disagree light illuminated; flight directors were out of view and yellow lines were through LNAV and VNAV on the ADI. Captain commented that the autoplt had gone into a degraded mode and that I was to fly the aircraft while he got into the checklist. It appeared that the standby dc bus had failed. At that time I called the cabin to have them send the other copilot back up; and he returned within a min or two. Captain went through the checklist and was unable to restore the bus. We were very concerned with the loss of pitot static heating; standby ADI; #1 radios; and the battery discharging to mention a few. We agreed that we should get out of the WX as soon as possible and divert. We were able to get a radio frequency on guard using radio #2 and were given a vector and descent. I disconnected the center autoplt and selected the right autoplt which restored full function. Captain and first officer began coordination with ATC; flight control and the flight attendants as I continued to fly the aircraft. We began dumping fuel to lower our weight for landing; ran the checklists. We lowered the gear early on a high downwind. At 6000 ft we were still in the WX and had to descend to 3000 ft before we were under it. We were vectored onto final and began to lower flaps and slow down. We decided on flaps 25 degrees for landing due to our heavy weight (approximately 355000 pounds). It was raining outside and we talked about making sure we were stopped before getting into the rubber deposits at the departure end of the runway to avoid any breaking problems. We also discussed using full reversers to aid in slowing down. The approach was very stable and on short final I dropped slightly below the GS approximately 1/2 DOT low to ensure maximum landing distance. There is a displaced threshold on runway 35L so I was not concerned with the maneuver. I touched down very smoothly and began to deploy the thrust reversers. I could not get the left reverser to deploy so I deployed the right one at a lower thrust setting to avoid any control problems on the wet runway. I then verbally announced it to the crew. Captain made a 150 KTS call; I waited a few seconds and was not happy with the deceleration rate so I began to apply manual braking. I tried to apply a constant but not too aggressive brake pressure. The braking appeared to be consistent with any other landing. I contacted ground clear of the runway and they asked us if we still needed to be an emergency aircraft. Captain wanted the fire trucks to follow us to the parking pad just in case there were any hot brake issues. We pulled into the pad; shut down and motioned for the ground crew to come up on a headset so we could confirm chocks were in and to stay away from the gear because the brakes were hot. The stairs were pulled up to the aircraft and the door opened. First officer got up to go check on the brakes. Shortly thereafter; the flight attendant stuck her head into the cockpit and said the brakes were on fire. Captain told her to get the people off the aircraft through the front door. She made a PA and the people began to leave the aircraft in an orderly manner. The captain noticed that some people were grabbing their belongings so he made a PA identing himself as the captain and told the passenger to leave their belongings behind and to gather in front of the aircraft. Just as the passenger were getting off the aircraft; busses began arriving to take them to the terminal. The fire was put out very quickly by the fire department. We elected to stay on the aircraft so we could use company radio to communicate with flight control and maintenance. Supplemental information from acn 694225: as the people were exiting the air stairs; a passenger bus suddenly appeared taking the people to the terminal. Finally; a mechanic showed up; and we explained the problem. He pointed to a circuit that had popped on the lower P-6 panel; the standby dc bus circuit breaker.

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Original NASA ASRS Text

Title: B767-300ER SUFFERS LOSS OF STANDBY ELECTRICAL SYS. DUMPS FUEL AND DIVERTS.

Narrative: WE WERE FLYING AT FL300 IN THE WX. I WAS THE RELIEF PLT AND THE COPLT (PF) HAD JUST LEFT FOR HIS BREAK. WE GOT AN AURAL WARNING AND THE FIRST THING I NOTICED WAS THE LEADING EDGE DISAGREE LIGHT ILLUMINATED; FLT DIRECTORS WERE OUT OF VIEW AND YELLOW LINES WERE THROUGH LNAV AND VNAV ON THE ADI. CAPT COMMENTED THAT THE AUTOPLT HAD GONE INTO A DEGRADED MODE AND THAT I WAS TO FLY THE ACFT WHILE HE GOT INTO THE CHKLIST. IT APPEARED THAT THE STANDBY DC BUS HAD FAILED. AT THAT TIME I CALLED THE CABIN TO HAVE THEM SEND THE OTHER COPLT BACK UP; AND HE RETURNED WITHIN A MIN OR TWO. CAPT WENT THROUGH THE CHKLIST AND WAS UNABLE TO RESTORE THE BUS. WE WERE VERY CONCERNED WITH THE LOSS OF PITOT STATIC HEATING; STANDBY ADI; #1 RADIOS; AND THE BATTERY DISCHARGING TO MENTION A FEW. WE AGREED THAT WE SHOULD GET OUT OF THE WX ASAP AND DIVERT. WE WERE ABLE TO GET A RADIO FREQ ON GUARD USING RADIO #2 AND WERE GIVEN A VECTOR AND DSCNT. I DISCONNECTED THE CTR AUTOPLT AND SELECTED THE R AUTOPLT WHICH RESTORED FULL FUNCTION. CAPT AND FO BEGAN COORD WITH ATC; FLT CTL AND THE FLT ATTENDANTS AS I CONTINUED TO FLY THE ACFT. WE BEGAN DUMPING FUEL TO LOWER OUR WT FOR LNDG; RAN THE CHKLISTS. WE LOWERED THE GEAR EARLY ON A HIGH DOWNWIND. AT 6000 FT WE WERE STILL IN THE WX AND HAD TO DSND TO 3000 FT BEFORE WE WERE UNDER IT. WE WERE VECTORED ONTO FINAL AND BEGAN TO LOWER FLAPS AND SLOW DOWN. WE DECIDED ON FLAPS 25 DEGS FOR LNDG DUE TO OUR HVY WT (APPROX 355000 LBS). IT WAS RAINING OUTSIDE AND WE TALKED ABOUT MAKING SURE WE WERE STOPPED BEFORE GETTING INTO THE RUBBER DEPOSITS AT THE DEP END OF THE RWY TO AVOID ANY BREAKING PROBS. WE ALSO DISCUSSED USING FULL REVERSERS TO AID IN SLOWING DOWN. THE APCH WAS VERY STABLE AND ON SHORT FINAL I DROPPED SLIGHTLY BELOW THE GS APPROX 1/2 DOT LOW TO ENSURE MAX LNDG DISTANCE. THERE IS A DISPLACED THRESHOLD ON RWY 35L SO I WAS NOT CONCERNED WITH THE MANEUVER. I TOUCHED DOWN VERY SMOOTHLY AND BEGAN TO DEPLOY THE THRUST REVERSERS. I COULD NOT GET THE L REVERSER TO DEPLOY SO I DEPLOYED THE R ONE AT A LOWER THRUST SETTING TO AVOID ANY CTL PROBS ON THE WET RWY. I THEN VERBALLY ANNOUNCED IT TO THE CREW. CAPT MADE A 150 KTS CALL; I WAITED A FEW SECONDS AND WAS NOT HAPPY WITH THE DECELERATION RATE SO I BEGAN TO APPLY MANUAL BRAKING. I TRIED TO APPLY A CONSTANT BUT NOT TOO AGGRESSIVE BRAKE PRESSURE. THE BRAKING APPEARED TO BE CONSISTENT WITH ANY OTHER LNDG. I CONTACTED GND CLR OF THE RWY AND THEY ASKED US IF WE STILL NEEDED TO BE AN EMER ACFT. CAPT WANTED THE FIRE TRUCKS TO FOLLOW US TO THE PARKING PAD JUST IN CASE THERE WERE ANY HOT BRAKE ISSUES. WE PULLED INTO THE PAD; SHUT DOWN AND MOTIONED FOR THE GND CREW TO COME UP ON A HEADSET SO WE COULD CONFIRM CHOCKS WERE IN AND TO STAY AWAY FROM THE GEAR BECAUSE THE BRAKES WERE HOT. THE STAIRS WERE PULLED UP TO THE ACFT AND THE DOOR OPENED. FO GOT UP TO GO CHK ON THE BRAKES. SHORTLY THEREAFTER; THE FLT ATTENDANT STUCK HER HEAD INTO THE COCKPIT AND SAID THE BRAKES WERE ON FIRE. CAPT TOLD HER TO GET THE PEOPLE OFF THE ACFT THROUGH THE FRONT DOOR. SHE MADE A PA AND THE PEOPLE BEGAN TO LEAVE THE ACFT IN AN ORDERLY MANNER. THE CAPT NOTICED THAT SOME PEOPLE WERE GRABBING THEIR BELONGINGS SO HE MADE A PA IDENTING HIMSELF AS THE CAPT AND TOLD THE PAX TO LEAVE THEIR BELONGINGS BEHIND AND TO GATHER IN FRONT OF THE ACFT. JUST AS THE PAX WERE GETTING OFF THE ACFT; BUSSES BEGAN ARRIVING TO TAKE THEM TO THE TERMINAL. THE FIRE WAS PUT OUT VERY QUICKLY BY THE FIRE DEPT. WE ELECTED TO STAY ON THE ACFT SO WE COULD USE COMPANY RADIO TO COMMUNICATE WITH FLT CTL AND MAINT. SUPPLEMENTAL INFO FROM ACN 694225: AS THE PEOPLE WERE EXITING THE AIR STAIRS; A PAX BUS SUDDENLY APPEARED TAKING THE PEOPLE TO THE TERMINAL. FINALLY; A MECH SHOWED UP; AND WE EXPLAINED THE PROB. HE POINTED TO A CIRCUIT THAT HAD POPPED ON THE LOWER P-6 PANEL; THE STANDBY DC BUS CIRCUIT BREAKER.

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.