Narrative:

I was PIC (PF). Just clearing runway 17 at azo. First officer (PNF) started APU as per normal operations. Nosewheel steering failed at starter engagement, causing us to very nearly run off the pavement. Through talking to others, I have found this to have happened to several other crews. This is a brand new, state of the art, highly automated aircraft, but it seems to have some logic and failure quirks that slipped at certification. One of our capts put it best by stating, 'if we ever lose a dornier, the last thing on the cvr will be 'now why do you suppose it did that?' callback conversation with reporter revealed the following information: reporter states that this newly certificated aircraft has a multitude of problems, some of them are currently receiving attention from involved manufacturers. Reporter is uncertain regarding electrical distribution system status, but reporter's company has taken action per chief pilot's influence. It was determined that the nosewheel steering failure (common problem) was directly related to the battery power control unit (bpcu), and specifically to nicad battery maintenance. Apparently, poor battery maintenance (deep cycling) was affecting battery capacity, and when the bpcu senses a drop in voltage, it isolates the batteries from the main buses, leaving only hot battery bus items powered. This scenario began during taxi through a 90 degree turn. The first officer was starting the APU which caused enough of a drop in voltage for the batteries to be isolated by the bpcu. Nosewheel steering, powered by a non-essential bus, failed as a result. The nosewheel went to centering, and the captain was forced to jump on differential steering (braking) in order to regain aircraft control. Since the reporter has been flying the dornier 328-100 he has experienced a shattered windshield, bleed failure (both), EFIS course needle 'freezing,' landing gear extension fail caused by fairing and fuselage buckling differences, and bogus EICAS messages. He has received messages that don't even apply to his aircraft, such as 'ground spoilers armed,' 'heads- up display inoperative,' and hydraulic system problems.

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Original NASA ASRS Text

Title: THE CAPT OF A DORNIER 328 LOST NOSEWHEEL STEERING CAPABILITY DURING TAXI WHILE TURNING. ELECTRICAL SYS DISTRIBUTION DESIGN AND BATTERY MAINT WERE DETERMINED TO BE THE CAUSE OF THE FAILURE.

Narrative: I WAS PIC (PF). JUST CLRING RWY 17 AT AZO. FO (PNF) STARTED APU AS PER NORMAL OPS. NOSEWHEEL STEERING FAILED AT STARTER ENGAGEMENT, CAUSING US TO VERY NEARLY RUN OFF THE PAVEMENT. THROUGH TALKING TO OTHERS, I HAVE FOUND THIS TO HAVE HAPPENED TO SEVERAL OTHER CREWS. THIS IS A BRAND NEW, STATE OF THE ART, HIGHLY AUTOMATED ACFT, BUT IT SEEMS TO HAVE SOME LOGIC AND FAILURE QUIRKS THAT SLIPPED AT CERTIFICATION. ONE OF OUR CAPTS PUT IT BEST BY STATING, 'IF WE EVER LOSE A DORNIER, THE LAST THING ON THE CVR WILL BE 'NOW WHY DO YOU SUPPOSE IT DID THAT?' CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT THIS NEWLY CERTIFICATED ACFT HAS A MULTITUDE OF PROBS, SOME OF THEM ARE CURRENTLY RECEIVING ATTN FROM INVOLVED MANUFACTURERS. RPTR IS UNCERTAIN REGARDING ELECTRICAL DISTRIBUTION SYS STATUS, BUT RPTR'S COMPANY HAS TAKEN ACTION PER CHIEF PLT'S INFLUENCE. IT WAS DETERMINED THAT THE NOSEWHEEL STEERING FAILURE (COMMON PROB) WAS DIRECTLY RELATED TO THE BATTERY PWR CTL UNIT (BPCU), AND SPECIFICALLY TO NICAD BATTERY MAINT. APPARENTLY, POOR BATTERY MAINT (DEEP CYCLING) WAS AFFECTING BATTERY CAPACITY, AND WHEN THE BPCU SENSES A DROP IN VOLTAGE, IT ISOLATES THE BATTERIES FROM THE MAIN BUSES, LEAVING ONLY HOT BATTERY BUS ITEMS POWERED. THIS SCENARIO BEGAN DURING TAXI THROUGH A 90 DEG TURN. THE FO WAS STARTING THE APU WHICH CAUSED ENOUGH OF A DROP IN VOLTAGE FOR THE BATTERIES TO BE ISOLATED BY THE BPCU. NOSEWHEEL STEERING, POWERED BY A NON-ESSENTIAL BUS, FAILED AS A RESULT. THE NOSEWHEEL WENT TO CENTERING, AND THE CAPT WAS FORCED TO JUMP ON DIFFERENTIAL STEERING (BRAKING) IN ORDER TO REGAIN ACFT CTL. SINCE THE RPTR HAS BEEN FLYING THE DORNIER 328-100 HE HAS EXPERIENCED A SHATTERED WINDSHIELD, BLEED FAILURE (BOTH), EFIS COURSE NEEDLE 'FREEZING,' LNDG GEAR EXTENSION FAIL CAUSED BY FAIRING AND FUSELAGE BUCKLING DIFFERENCES, AND BOGUS EICAS MESSAGES. HE HAS RECEIVED MESSAGES THAT DON'T EVEN APPLY TO HIS ACFT, SUCH AS 'GND SPOILERS ARMED,' 'HEADS- UP DISPLAY INOP,' AND HYD SYS PROBS.

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.