Date: 201402
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Weather elements / visibility: Fog
Light: Daylight
Aircraft: A319
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Aircraft component: Main Gear
Reporter organization: Air Carrier
Reporter function: Technician
Reporter qualification: Maintenance Airframe; Maintenance Powerplant
Human factors: Communication Breakdown; Workload
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Maintenance
Result: General Maintenance Action
Contributing factors: Aircraft; Chart Or Publication; Human Factors; Procedure; Weather
Primary problem: Human Factors

Narrative: I was assigned to work on an A319 aircraft with the following workload:1) Overnight Check accomplished      2) Electronic Flight Bag (EFB) deactivation by an Engineering Order (E/O) accomplished.  3) EFB on MEL accomplished.     4) Brake Fan-inoperative on MEL. I started with the Overnight Check; EFB deactivation; and the EFB MEL.  Performed troubleshooting of the Brake Fan MEL using Troubleshooting Manual; Step-1 through 4a.  Verifying condition of the Circuit Breakers (C/B) and performed Operational Check as stated in the TSM.  No sign of tripped circuit breaker noted.  Tried to reset the circuit breakers a couple of times and did Operational Check.  Brake Fan System 1-2 still inoperative (System inop).  Performed General Visual Inspection (GVI) of the Left MLG and found slightly kinked conduit in the lower torque link area (fwd side). As no additional damage was noted; I updated the MEL by programming the required (L/H MLG harness 2M) part for replacement.  No evidence of perforation or hole.  No evidence of burn/arcing.  No broken [wire] strands.  Notified by Flight Safety Committee in ZZZ.  Logpage updated in ZZZ1 nine days later and Removed and Replaced (R/R) Left MLG 2M harness part in ZZZ2 two days after that. [Recommend] to prevent Electrical Wiring Interconnect System (EWIS) issues; [have] better conduit routing.   Detailed Visual Inspection (DVI) of the harness on a regular basis [instead of a General visual Inspection (GVI).  [Add] MEL procedure to collar the Circuit Breakers.   [Add] Inspection criteria limitation for the conduit. Cold excessive. Fog. Routine Overnight Maintenance (RON).

Callback: Reporter stated the A319 came in with an MEL for the electric Brake Fans not cooling.  The fans are installed in the center of the axle and over the axle wheel nut threads prior to installing the tire locking nut. Four cooling fans; separated into Left MLG # 1-2 and Right MLG # 3-4. There are two; Brake Fan Circuit Breakers for the Left-Right MLGs in cockpit; but only one switch for operating all brake fans located just above the Landing Gear Lever. He troubleshot the Brake Fan System and noticed the Left MLG # 1-2 fans were not operating; but C/B for that group had not popped. The Right MLG fans # 3-4 were OK.  Reporter stated the Brake Fan harness runs from the top forward side of the of the MLG down the forward side of the MLG strut to a lower bracket where the harness and internal wiring is separated and becomes two flexible conduits for the Inboard (I/B) and  Outboard (O/B) brakes.  He found both flexible harnesses kinked just below the flex harness connectors at the lower bracket.  He has seen numerous kinked harnesses at the same location on A319s only; not on the A320s. He suspects that fatigue failure of the flexible conduit material from extension/retraction of the MLGs may be the issue. He did not know if stretching of the harnesses at that location may also be contributing to the deterioration of the harness. The Aircraft Maintenance Manual (AMM) and the Component Maintenance Manual (CMM) do not really address the type of damage he has been seeing.  Some A319 Operators do not have Brake Cooling fans for their Main Landing Gear (MLG) brakes. The Electronic Flight Bag (EFB) was deactivated because his Air Carrier is transitioning to I-Pads for their pilots.



Synopsis: A Line Aircraft Maintenance Technician (AMT) describes his Overnight Check workload that included a General Visual Inspection (GVI) of the left Main Landing Gear (MLG) wire harness on an A319 aircraft. Harness was replaced several days later due to Electrical Wiring Interconnection System (EWIS) issues associated with electrical harness damage.