While taxiing from the hangar to the terminal with only #2 engine and APU running on an airbus A320;...

Attributes
ACN	808781
Time
Date	200810
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Person 1
Affiliation	other
Function	maintenance : technician
ASRS Report	808781
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other other : 1
Resolutory Action	other
Consequence	other
Factors
Maintenance	contributing factor : briefing performance deficiency : testing
Supplementary
Problem Areas	Aircraft Maintenance Human Performance
Primary Problem	Aircraft

Narrative:

I was taxiing an airplane from the hangar to the terminal and I was taxiing on 1 engine due to the fact that the fuel on the left side was below minimum to taxi with. I lost nosewheel steering when I was cleared to cross the active runway. I had the APU running and the electric hydraulic pumps on. Notified ground control that I lost nosewheel steering; that I was stopping to correct the problem. I returned to the hangar and inspected the nose gear and steering system; nose discrepancies noted. I then taxied the aircraft on both engines to the line without incident. Taxiing on 1 engine instead of using both engines to taxi on; in order to have full nosewheel steering. Taking time to make sure that I follow the guidelines; when taxiing the airbus aircraft in the future. Callback conversation with reporter revealed the following information: reporter stated after returning to hanger; the brake steering control unit (bscu) and nose steering seemed to function properly. Reporter stated he was informed by other mechanics; that a specific circuit breaker could be pulled that would prevent the loss of nose wheel steering during a one-engine taxi of the airbus A320. But he couldn't remember at the moment which one.

Original NASA ASRS Text

Title: WHILE TAXIING FROM THE HANGAR TO THE TERMINAL WITH ONLY #2 ENGINE AND APU RUNNING ON AN AIRBUS A320; MECHANIC REPORTS HE LOST NOSE WHEEL STEERING JUST WHEN HE WAS CLEARED TO CROSS THE ACTIVE RUNWAY. BRAKE STEERING CONTROL UNIT (BSCU) IS SUSPECTED.

Narrative: I WAS TAXIING AN AIRPLANE FROM THE HANGAR TO THE TERMINAL AND I WAS TAXIING ON 1 ENG DUE TO THE FACT THAT THE FUEL ON THE L SIDE WAS BELOW MINIMUM TO TAXI WITH. I LOST NOSEWHEEL STEERING WHEN I WAS CLRED TO CROSS THE ACTIVE RWY. I HAD THE APU RUNNING AND THE ELECTRIC HYD PUMPS ON. NOTIFIED GND CTL THAT I LOST NOSEWHEEL STEERING; THAT I WAS STOPPING TO CORRECT THE PROB. I RETURNED TO THE HANGAR AND INSPECTED THE NOSE GEAR AND STEERING SYS; NOSE DISCREPANCIES NOTED. I THEN TAXIED THE ACFT ON BOTH ENGS TO THE LINE WITHOUT INCIDENT. TAXIING ON 1 ENG INSTEAD OF USING BOTH ENGS TO TAXI ON; IN ORDER TO HAVE FULL NOSEWHEEL STEERING. TAKING TIME TO MAKE SURE THAT I FOLLOW THE GUIDELINES; WHEN TAXIING THE AIRBUS ACFT IN THE FUTURE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED AFTER RETURNING TO HANGER; THE BRAKE STEERING CONTROL UNIT (BSCU) AND NOSE STEERING SEEMED TO FUNCTION PROPERLY. REPORTER STATED HE WAS INFORMED BY OTHER MECHANICS; THAT A SPECIFIC CIRCUIT BREAKER COULD BE PULLED THAT WOULD PREVENT THE LOSS OF NOSE WHEEL STEERING DURING A ONE-ENGINE TAXI OF THE AIRBUS A320. BUT HE COULDN'T REMEMBER AT THE MOMENT WHICH ONE.

Data retrieved from NASA's ASRS site as of May 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.

While taxiing from the hangar to the terminal with only #2 engine and APU running on an airbus A320; mechanic reports he lost nose wheel steering just when he was cleared to cross the active runway. Brake steering control unit (bscu) is suspected.