Narrative:

As a jumpseat rider from sydney to lax, I became concerned with both the computer problems on the widebody transport and the degree of ATC overload in lax. Coming into lax, ATC asked us to increase our speed from 180 KTS to 230 KTS. It was clear that we were going to be too high, but the controller was too busy for us to be able to interrupt his flow of instructions to let him know we were too high. Finally he cleared us for the approach and apologized for clearing us late and asked if we could get down ok? As it turned out we could not, and elected to go around. After the to GA switch had been pushed to go around, the pitch mode engaged correctly but the pilots were unable to get the roll mode to disengage from localizer capture, even after trying several alternate methods of doing so. Eventually the computer functioned normally after the copilot selected another approach with numerous entries tried. This required a lot of 'heads down' work at a time when it was most undesirable. When the pilot advised ATC that he would go around, they told us to fly runway heading and climb to 5000'. That would have put us right through a busy VFR corridor that extends from 2500' to 4500'. The cloud base was 4000' and the captain elected to delay the climb. The computer problem described here was not the only one on this long leg, and there had also been one the day before. (At that time, the captain wanted to hand fly it because of a computer problem and needed to enter a new frequency, but could not do so because the 'scratch pad' was full, and could not clear the scratch pad because of the computer malfunction! I was not in the cockpit then, so this is second hand. But the crew really wished there were dials to set frequencys when necessary). It is disturbing to see how much 'heads down' time is involved in all of the computer problems. A final comment about what appeared to be a controller overload: the controller was talking so fast he sounded like an auctioneer; in addition to being unable to break in, I am sure that some pilots whose native tongue was not english would have had great difficulty understanding him. Even for american pilots, the combination of computer problems and ATC overload could easily prove fatal.

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Original NASA ASRS Text

Title: ACR ADVTECH WDB EXECUTES GO AROUND BECAUSE OF BEING UNABLE TO COMPLY WITH ATC CLRNC AND MAINTAIN STABILIZED APCH.

Narrative: AS A JUMPSEAT RIDER FROM SYDNEY TO LAX, I BECAME CONCERNED WITH BOTH THE COMPUTER PROBS ON THE WDB AND THE DEG OF ATC OVERLOAD IN LAX. COMING INTO LAX, ATC ASKED US TO INCREASE OUR SPD FROM 180 KTS TO 230 KTS. IT WAS CLR THAT WE WERE GOING TO BE TOO HIGH, BUT THE CTLR WAS TOO BUSY FOR US TO BE ABLE TO INTERRUPT HIS FLOW OF INSTRUCTIONS TO LET HIM KNOW WE WERE TOO HIGH. FINALLY HE CLRED US FOR THE APCH AND APOLOGIZED FOR CLRING US LATE AND ASKED IF WE COULD GET DOWN OK? AS IT TURNED OUT WE COULD NOT, AND ELECTED TO GO AROUND. AFTER THE TO GA SWITCH HAD BEEN PUSHED TO GO AROUND, THE PITCH MODE ENGAGED CORRECTLY BUT THE PLTS WERE UNABLE TO GET THE ROLL MODE TO DISENGAGE FROM LOC CAPTURE, EVEN AFTER TRYING SEVERAL ALTERNATE METHODS OF DOING SO. EVENTUALLY THE COMPUTER FUNCTIONED NORMALLY AFTER THE COPLT SELECTED ANOTHER APCH WITH NUMEROUS ENTRIES TRIED. THIS REQUIRED A LOT OF 'HEADS DOWN' WORK AT A TIME WHEN IT WAS MOST UNDESIRABLE. WHEN THE PLT ADVISED ATC THAT HE WOULD GO AROUND, THEY TOLD US TO FLY RWY HDG AND CLB TO 5000'. THAT WOULD HAVE PUT US RIGHT THROUGH A BUSY VFR CORRIDOR THAT EXTENDS FROM 2500' TO 4500'. THE CLOUD BASE WAS 4000' AND THE CAPT ELECTED TO DELAY THE CLB. THE COMPUTER PROB DESCRIBED HERE WAS NOT THE ONLY ONE ON THIS LONG LEG, AND THERE HAD ALSO BEEN ONE THE DAY BEFORE. (AT THAT TIME, THE CAPT WANTED TO HAND FLY IT BECAUSE OF A COMPUTER PROB AND NEEDED TO ENTER A NEW FREQ, BUT COULD NOT DO SO BECAUSE THE 'SCRATCH PAD' WAS FULL, AND COULD NOT CLR THE SCRATCH PAD BECAUSE OF THE COMPUTER MALFUNCTION! I WAS NOT IN THE COCKPIT THEN, SO THIS IS SECOND HAND. BUT THE CREW REALLY WISHED THERE WERE DIALS TO SET FREQS WHEN NECESSARY). IT IS DISTURBING TO SEE HOW MUCH 'HEADS DOWN' TIME IS INVOLVED IN ALL OF THE COMPUTER PROBS. A FINAL COMMENT ABOUT WHAT APPEARED TO BE A CTLR OVERLOAD: THE CTLR WAS TALKING SO FAST HE SOUNDED LIKE AN AUCTIONEER; IN ADDITION TO BEING UNABLE TO BREAK IN, I AM SURE THAT SOME PLTS WHOSE NATIVE TONGUE WAS NOT ENGLISH WOULD HAVE HAD GREAT DIFFICULTY UNDERSTANDING HIM. EVEN FOR AMERICAN PLTS, THE COMBINATION OF COMPUTER PROBS AND ATC OVERLOAD COULD EASILY PROVE FATAL.

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.