FAA's Reported Wire Incidents – January 2009

Author: Lectromec GSD Team

March 3, 2009

 The following are the wire incidents reported in the FAA’s January 2009 Advisory Circular 43-16A – Alert Number 366 [Original Document Here] http://www.faa.gov/aircraft/safety/alerts/aviation_maintenance/media/2009/2009_01_Alert.pdf

Incident #1

Aircraft Make: Beechjet

Aircraft Model: 400A

Part Name: Wire

Part Condition: Chafing

Part Location: Right Forward Galley

"The pitch-trim (was found to be) inoperative. (I) removed the right forward galley and the right forward partition. A wire bundle was found chafed behind the partition. I repaired three wires that were chafed (completely) through to the conductors. Clearance was provided between the wire bundle and the partition, and anti-chafe material was installed. At the time of the repair no other components had malfunctioned from the other two chafed wires."

Incident #2

FAA Control Number: CA081113002

Part Name: Wire

Part Condition: Chafed

Difficultly Date: 11/13/2008

Part Location: Magneto

(can) coil to points wire worn through to strands due to rubbing on frame of distributor block.

Incident #3

FAA Control Number: CA081207001

Aircraft Make: LYC

Aircraft Model: DC981

Part Name: Magneto

Part Condition: Failed

Difficultly Date: 12/2/2008

Part Location: Engine

(Can) after start MAG check performed and LT MAG failed. MX was notified and when MAG was looked at found that the breaker point wires had vibrated off. Wires repaired and reinstalled.

Incident #4

FAA Control Number: CA081118001

Aircraft Make: Beech

Aircraft Model: 300Beech

Part Name: Relay

Part Condition: Unserviceable

Part Number: MS24166DI

Difficultly Date: 11/15/2008

Part Location: Windshield heat

(Can) crew defect pilot windshield heat not working, troubleshoot to low heat relay, terminal a2 melted off the relay assy, damaging wires attached to the terminal approx 3 inches back the wire cover melted off. Relay was replaced and sys operates properly.

Incident #5

FAA Control Number: 2008FA0000842

Aircraft Make: Bell

Aircraft Model: 206B3

Part Name: Ground Wire

Part Condition: Missing

Difficultly Date: 11/24/2008

Part Location: Boost Pump

Mfg has removed a ground wire from both electric boost pumps. Ground has been on earlier models, removed since SAN: 4205 JAW wiring diagrams. Caution lights for boost pumps not operational since no ground available to base of pressure switch. Ground wire installed from motor housing to base of boost pump. Mm shows ground wire to base of boost pump 206-062-681-101. Ops normal after ground routed to base of boost pump.

Incident #6

FAA Control Number: CA081125001

Aircraft Make: Boeing

Aircraft Model: 75728A

Part Name: Wire Harness

Part Condition: Chafed

Difficultly Date: 11/25/2008

(CAN) in flight crew noticed smoke and flashes above row 4DEF. MX found wiring harness chafed by ceiling panel resulting in exposed wires arching.

Incident #7

FAA Control Number: CA081114001

Aircraft Make: Bombardier

Aircraft Model: DHC8400

Part Name: Wire Harness

Part Condition: Shorted

Location: Proximity Switch

Difficultly Date: 11/13/2008

(CAN) crew selected gear down and got 3 greens and LT MLG door amber light. Alternate extension c/o and crew observed alternate indication showed LT MLG (unsafe). Crew declared emergency and landed. Pax deplaned on runway and after gears were pinned acft taxied to gate. Fault confirmed by pseu to be LT LGDNLK2 open circuit. Proximity switch harness assy PN 46460-5 replaced and acft returned to service.

Incident #8

FAA Control Number: CA081112002

Aircraft Make: Bombardier

Aircraft Model: DHC8400

Part Name: Shroud

Part Condition: Mis-manufactured

Location: Wing Box

Difficultly Date: 5/29/2008

(CAN) during production of 4208 it was discovered that the center wing lower shroud RT drain holes were not present. A discrepancy was raised and cleared by drilling new holes in siter. Upon the delivery/acceptance flight, it was discovered that the aft coffee marker was unserviceable. A technical investigation revealed 6 of 9 (115 VAC) wires damaged. A repair was made JAW WDM 20-16-00. A SMS/SRS was raised.

Incident #9

FAA Control Number: 2008FA0000853

Aircraft Make: Cessna

Aircraft Model: T303

Part Name: Alternator

Part Condition: Shorted

Location: Engine

Difficultly Date: 11/30/2008

Have had multiple failures, both in flight and during maintenance ground operations. Hours on failed alternators range from as low as 30 to a maximum of 220 hours time in service. The one common factor in all failures has been the discovery of loose hex head case bolts installed and safety wired by manufacturer. This problem is not restricted to one side only, both engines drive the same alternator with same part number.

Incident #10

FAA Control Number: CA081024006

Aircraft Make: Lear

Aircraft Model: 45Lear

Part Name: Ground Wire

Part Condition: Open

Location: Trim System

Difficultly Date: 10/10/2008

(Can) on landing, a white CAS message (secondary trim fault) appeared. Sys troubleshot and found an open ground wire at rba0664n-22 at splicesp322. Splice repaired and function checked serviceable.

Incident #11

FAA Control Number: CA081001006

Aircraft Make: Urocop

Aircraft Model: EC130B4

Part Name: Wire

Part Condition: Shorted

Location: Comm1

Difficultly Date: 9/24/2008

(CAN) No pilot or copilot side tone on comm 1. Tech found the audio phone wire shorted by the shielding. Repaired and side tones were returned to normal.