N168ZZ
Registered owner: BWC HOLDINGS LTD, CO (owner ≠ operator)
Operators of this aircraft
Who operated this tail, and how firmly we know it.
No operator established for this aircraft.
Accident & incident history
No NTSB accidents or incidents on file for this aircraft.
Maintenance disclosures
REPETITIVE FAILURES OF NOSE WHEEL STEERING FAILURE. AFTER EXTENSIVE HOURS OF TROUBLESHOOTING CONTACT WITH LEARJET ENGINEERING SUPPORT, AND REPLACEMENT OF THE NOSE WHEEL STEERING SERVO, WE HAVE FOUND THAT THE PROBLEM WAS DUE TO A BAD NR 4 MAIN WHEEL SPEED SENSOR (TRANSDUCER). NOTHING IN THE MAINTENANCE MANUAL OR TROUBLESHOOTING PROCEDURES EVEN SUGGESTS THAT A WHEEL SPEED SENSOR CAN CAUSE THIS PROBLEM. THE TECHNICIANS HERE DID A GOOD JOB OF ISOLATING AND FINDING THE PROBLEM. IN REALITY, LEARJET DID NOT HAVE AN EXPLANATION FOR WHAT WAS HAPPENING. THE LEAD TECHNICIAN REALIZED THAT THE FAILURE WAS NOT OCCURRING WHILE PERFORMING THE OPERATION CHECKS STATICALLY. IT ONLY OCCURRED WHILE TAXING AND AT A CERTAIN SPEED. IN SHORT, THE NR 4 SPEED SENSOR WAS FAILING ONLY AT ABOUT THE 10 KNOT RANGE OF WHEEL SPEED. AT ZERO KNOTS AND ABOVE 50 KNOTS THE SENSOR WAS OK, BUT AT AROUND 10 KNOTS THE COMPUTER SHOWED EXTREME ERRATIC READINGS. THE COMPUTER SHOWED ALL OTHER WHEEL SPEED SENSORS OPERATING NORMALLY.
DURING INSPECTION FOUND CORROSION ON ENGINE MOUNT PADS. CORROSION FOUND ON THREE OF THE FOUR MOUNT PADS AND WAS WITHIN PWC MAINTENANCE MANUAL 72-30-01 LIMITS. REMOVED AND TREATED CORROSION PER MAINTENANCE MANUAL 72-30-01.
DURING INSPECTION, FOUND CORROSION ON ENGINE MOUNT PADS. CORROSION WAS ON TWO OF THE FOUR MOUNT PADS. CORROSION WAS BEYOND PWC MAINTENANCE MANUAL 72-30-01 LIMITS. SUBMITTED DESCRIPTION OF CORROSION TO PWC. DEVIATION LETTER OBTAINED FROM PRATT WHITNEY CANADA STATING THAT REPAIR OF THE INTERMEDIATE CASE MOUNTING PADS CAN BE DEFERRED UNTIL NEXT SCHEDULED SHOP VISIT NO LATER THAT 3100 CYCLES SINCE NEW PROVIDED THAT THE ENGINE IS ONLY OPERATED ON THE RT SIDE OF AIRCRAFT AND REPAIR OF CORROSION TOO LIMIT PROGRESSION IS PERFORMED. CORROSION WAS REPAIRED AND ENGINE WAS MOVED TO THE RT SIDE OF AIRCRAFT SO THAT THE DAMAGED MOUNT PADS ARE NOT IN USE.