The following are the wire incidents reported in the FAA’s October 2008 Advisory Circular 43-16A – Alert Number 363 and November 2008 Advisory Circular 43-16A – Alert Number and 364.
Incident #1
DASSAULTDassault: 900B; Failed Circuit Breaker; ATA 2400
A repair station report states:
While troubleshooting AC electrical outlets for being inoperative,(we) removed a floor panel to access the AC inverter and smelled burning plastic. We found this system had self-resetting circuit breakers installed that had been(resetting themselves)—and were continuing to reset (themselves)—allowing the Kapton wire insulation and spiral wrap to burn. One of the areas that burned was only three inches below a carbon flight control rod. I believe had this happened on a very long flight the outcome could have been very tragic. (It is suggested…) replacing these circuit breakers with (manually operated) circuit breakers would prevent the damage (which this report describes). [Original Part: Kilxon Circuit breaker; P/N M13516/5-1; aircraft total time not provided.]
Part Total Time: (unknown).
Incident #2
- FAA Control Number: GUU2008F00065
- Aircraft Make: Beech
- Aircraft Model: 1900D
- Part Name: Wire
- Part Condition: Out of Position
- Difficultly Date: 9/14/2008
- Part Location: Landing Light
After takeoff upon turning both landing lights switches off there was a spark coming out of the switch. Spliced and repositioned wire at LT landing light switch.Ops check good. (k)
Incident #2
- FAA Control Number: USA2008F00031
- Aircraft Make: Boeing
- Aircraft Model: 7373G7
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 09/15/2008
- Part Location: Emergency Lights
Maintenance reported the emergency escape path light on seat row 22, LT side, inoperative. Maintenance troubleshot and found a broken wire. Operational check good. (k)
Incident #3
- FAA Control Number: USA2008F00032
- Aircraft Make: Boeing
- Aircraft Model: 7374B7
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 09/15/2008
- Part Location: Emergency Lights
Maintenance reported the seat mounted emergency lights from seat rows 20 to 25 inoperative. Maintenance found a broken wire. Spliced wires together. Operational check good. (k)
Using undersized clamps can damage wires and create hot spots in the harnesses
Incident #4
- FAA Control Number: USA2008F00029
- Aircraft Make: Boeing
- Aircraft Model: 7374B7
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 09/13/2008
- Part Location: Emergency Lights
Maintenance reported the emergency escape path lighting from seat rows 19 to 25, LT side, inoperative. Maintenance repaired wiring at seat row 25 IAW standard practices. Emergency lighting operationally checks satisfactory. (k)
Incident #5
- FAA Control Number: EIA2008050
- Aircraft Make: Boeing
- Aircraft Model: 747212B
- Part Name: Wire
- Part Condition: Damaged
- Difficultly Date: 09/17/2008
- Part Location: Emergency Lights
Each emergency light on upper deck ceiling are out. Emergency light assy U/D aft replaced IAW mm 33-51-00. Ops checked normal. Repaired wire at pin NR 3 broken at kite assy IAW standard practices also repaired pin IAW manual ops checked normal. (k)
Incident #6
- FAA Control Number: NWAA084196309
- Aircraft Make: Boeing
- Aircraft Model: 747451
- Part Name: Wire
- Part Condition: Loose
- Difficultly Date: 09/8/2008
- Part Location: Emergency Lights
During over night check, found emergency floor lights from row 51 to 65 ABC inoperative. Maintenance repaired loose wire at pin connection. Ops checked good, and aircraft was returned to service.
Incident #7
- FAA Control Number: 2008FA0000671
- Aircraft Make: Cessna
- Aircraft Model: 208B
- Part Name: Wire Harness
- Part Condition: Chafed
- Difficultly Date: 09/24/2008
- Part Location: Flap System
Tie wrap was missing from the clamp at FS 201.50, which allowed the wiring bundle containing the wires for the flap sys primary motor to sag and chafe through wire NR CC75 to the flap system and partially through LA61 to the cargo area lights on the bulkhead. This caused the flaps to only receive power to the primary motor in one direction. Since wire LA61 wasn’t chaffed completely through the cargo area lights were still working.
Incident #8
- FAA Control Number: COMA0860391
- Aircraft Make: CNDAIR
- Aircraft Model: CL6002B19
- Part Name: Wire Harness
- Part Condition: Failed
- Difficultly Date: 09/15/2008
- Part Location: NLG
Received gear disagree MSG on T/O. NLG did not retract. Performed GRH for gear disagree. Emergency declared, A/C returned back and landed safely. Removed and replaced NLG WOW NR 2 wire harness.
Incident #9
- FAA Control Number: COMA0860390
- Aircraft Make: CNDAIR
- Aircraft Model: CL6002B19
- Part Name: Wire Harness
- Part Condition: Failed
- Difficultly Date: 09/12/2008
- Part Location: RT MLG
On climbout, received anti-skid caution MSG. Emergency declared, A/C returned back and landed safely. Removed and replaced RT MLG OB anti-skid wire harness.
Incident #10
- FAA Control Number: MWE2008F00038
- Aircraft Make: DOUG
- Aircraft Model: DC981
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 08/27/2008
- Part Location: Emergency Light
Emergency floor level lights out row 5-8. Found broken wire and repaired.
Incident #11
- FAA Control Number: AALA200802267
- Aircraft Make: DOUG
- Aircraft Model: DC983
- Part Name: Wire Harness
- Part Condition: Loose
- Difficultly Date: 09/03/2008
- Part Location: Cabin
Emergency light at seat 15D inoperative. Secured wire harness for emergency light at seat 15D. System ground checked normal operation.
Incident #12
- FAA Control Number: WGE2008F00002
- Aircraft Make: Eclipse
- Aircraft Model: Eclipse A500
- Part Name: Wire
- Part Condition: Damaged
- Difficultly Date: 09/02/2008
- Part Location: Overheat Sensor
Repaired fire overheat sensor high wire engine R0612-22 IAW EA 500 wiring repair manual section 3.27 for ops check C/W fire detection wire adjustment/ test IAW EA500, AMM 26-10-00-071-801. Ops check good. Reference log page 0875, DIS NR 2.
Incident #13
- FAA Control Number: C2X2008F00043
- Aircraft Make: EMB
- Aircraft Model: EMB145EP
- Part Name: Wire Harness
- Part Condition: Burned
- Difficultly Date: 09/07/2008
- Part Location: Emergency Lights
During preflight inspection the crew reported a smoke odor coming from seats 3 & 4a. The A/C was released on MEL 33-20-00 Cat C control NR 153947. The ac landed, where maintenance removed and replaced the light socket harness assy at row 4A, operationally checked with no defects, removed the MEL, and the A/C was approved for return to service.
Incident #14
- FAA Control Number: RAIA00809029
- Aircraft Make: EMB
- Aircraft Model: EMB145EP
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 09/27/2008
- Part Location: NLG WOW
Landing gear air/ground fail message on the EICAS. Maintenance found a broken wire at the NLG WOW switch. Wires were repaired and ops check proved good fix.
Incident #15
- FAA Control Number: FDK2008F00011
- Aircraft Make: EMB
- Aircraft Model: EMB145LR
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 09/09/2008
- Part Location: Emergency Lights
Both lower exit signs and 2 floor strips inoperative. Maintenance repaired broken wire at lower assy.
Incident #16
- FAA Control Number: C2XA08CL102
- Aircraft Make: EMB
- Aircraft Model: EMB145LR
- Part Name: Wire Harness
- Part Condition: Defective
- Difficultly Date: 08/31/2008
- Part Location: NLG
CLE flight NR2320 the crew reported an air/ground fail message in flight. The gear would not retract. The A/C returned to CLE and landed without incident. Maintenance inspected and replaced the nose gear wow harness and proximity switch. Ops checks were good.
Incident #17
- FAA Control Number: JJW2008F00000
- Aircraft Make: ROBSIN
- Aircraft Model: R44RavenII
- Part Name: Wire
- Part Condition: Chafed
- Difficultly Date: 03/25/2008
- Part Location: Cabin Air
Found wiring to freeze switch had chafed through the capillary tube temp sensor releasing all its refrigerant, causing switch to open and not allow compressor to run. Switch not field replaceable, had to sent to factory for repairs. Installed spiral wrap anti-chafe to wiring on repaired part to prevent reoccurrence. Notified mfg product support of problem and was told a service bulletin would be issued.
Incident #18
- FAA Control Number: 2008FA0000685
- Aircraft Make: LEAR
- Aircraft Model: 45LEAR
- Part Name: Wire
- Part Condition: Chafed
- Difficultly Date: 09/26/2008
- Part Location: Fire Detection
APU fire detection circuit breaker popped on RT cockpit circuit breaker panel during power up of aircraft. Troubleshot system found wiring chafed at fuselage station 614.210 aft equipment bay upper avionics shelf support angle PN 4525708307. The angle does not have any protection to prevent chafing of wiring from the factory and it appears that clearance is not great enough to keep the wiring from chafing. Have notified mfg tech support.
Incident #19
- FAA Control Number: M7KA0628084134
- Aircraft Make: UROCOP
- Aircraft Model: EC130B4
- Part Name: Wire Harness
- Part Condition: Damaged
- Difficultly Date: 09/01/2008
- Part Location: Potentiometer
Failure code at shutdown indicated fault with the collective potentiometer. A new potentiometer was installed and no further defect reported. It was recently discovered that the routing of air conditioning system wiring in contact with the unshielded electrical harness for the potentiometer was causing spurious signals in the control data which were interpreted as a pontentiometer failure. Dozens of these pontentiometers were replaced. Rerouting the air conditioning wiring has almost entirely eliminated the need to replace these potentiometers.
Incident #20
- FAA Control Number: MWE2008F00032
- Aircraft Make: Douglas
- Aircraft Model: DC981
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 08/19/2008
- Part Location: Emergency Light
Emergency floor level lights inoperative from row 9 to 20. Repaired broken wire in center section of light track.
Incident #21
- FAA Control Number: 2008FA0000561
- Aircraft Make: Piper
- Aircraft Model: PA44180
- Part Name: Wire
- Part Condition: Broken
- Difficultly Date: 05/13/2008
- Part Location: Alternator
Internal failure due to broken wires internally, heavy sparking inside engine compartment.
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