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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

HP CORE HARNESS CABLES CHAFING

•BACKGROUND

•PROBLEM CAUSE/CONSEQUENCES

• INVESTIGATION RESULT

• ACTION PLAN

• SCHEDULE

GE90 Product Reliability Team GE90 Product Reliability Team 09 NOVEMBER 1999 09 NOVEMBER 1999

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

BACKGROUND:

• EXAMINATION OF SEVERAL SCRAPPED HARNESSES HAS REVEALED CHAFING OF INTERNAL WIRES.

PTFE LINING & WIRES WEARING IN THE ELBOW BACKSHELLS FOR THE ALTERNATOR HARNESSES (W728) ARE THE MOST NUMEROUS (50%).

ALSO FOUND CHAFING ON OTHER CORE HARNESSES CABLES+ CHAFING ON STRAIGHT BACKSHELLS OR « T » AND « Y » TRANSITIONS.(See page 3)

Alternator harness-W728 (Elbow backshell) Alternator harness-W728 (Cables wearing)

Chafing area

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

4/11

ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

BACKGROUND:

ABOUT 194 GE90 CORE HARNESSES RETURNED AT SNECMA AFTER REMOVAL FROM 1998 TO 1999.

23 ELECTRICAL HARNESSES HAVE BEEN SCRAPPED FOR DAMAGED WIRES.

(MAJORITY OF CASES OCCURRED AT BRISTISH AIRWAYS)

OTHER 171 PBS INCLUDE EXTERNAL DAMAGE ( P.I. IN PLACE-HARNESS ROUTING AND IMPROVED CLAMPING) AND CONNECTOR DAMAGE (GE & SN. INVESTIGATING)

NOTE:

ALTERNATOR HARNESSES ( item 69S00-W728) ARE ESSENTIALLY IMPACTED.

(ABOUT 10 CASES FROM 1998 TO 1999)

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

PROBLEM CAUSE:

DAMAGE WIRES DUE TO ENGINE VIBRATIONS & CHAFING BETWEEN:

CABLES & CONNECTOR ELBOW BACKSHELLS (Alternator harnesses): 10 CASES

CABLES & TRANSITIONS-METAL : 4 CASES

CABLES & CIRCONVOLUTED PTFE SHEATH: 10 CASES*

* Damaged harnesses before the improvement of the harness clamping.

CONSEQUENCES:

FAULT MESSAGES BEING GENERATED

MAINTENANCE ACTIONS & CUSTOMER NUISANCE

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

6/11

ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

INVESTIGATION RESULT

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

INVESTIGATION RESULT

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

ACTION PLAN: SNECMA WORKING TEAM STRATEGY.

NECESSITY TO PROTECT THE CABLES IN THE ELBOW BACKSHELLS, TRANSITIONS METAL & CIRCONVOLUTED PTFE SHEATHS.

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

ACTION PLAN: (Following)1. CONSIDERED SOLUTIONS TO PROTECT THE CABLES:

VITON HEAT SHRINKABLE SHEATH (Difficult process implementation-rigidity)

VITON SMOOTH SHEAT (Used for SN. Engines harnesses)

NOMEX BRAID (Used for Fan harnesses)

KERMEL BRAID (Used for Core harnesses for other application)

SILICONE SHEATH (Inexperienced)

PTFE WRAPPING (Inexperienced for this application)

WRAP SELF CLOSING NOMEX (Inexperienced for this application)

2. POTENTIAL SOLUTIONS MUST BE EVALUATED TO CHECK:

THE MATERIAL SUPPLY AVAILABILITY

THE PROCESS IMPLEMENTATION FOR EACH HARNESS TYPES (model tests)

THE WEARING RESISTANCE (abrasion tests)

3. PROPOSED SOLUTION TO PROTECT THE CABLES FOR EACH HARNESS TYPES:

MUST BE VALIDATED WITH COMPLEMENTARY TESTS (TBD) & IN ACCORDANCE WITH MUST BE VALIDATED WITH COMPLEMENTARY TESTS (TBD) & IN ACCORDANCE WITH THE GE90 MATRIX REQUIREMENTSTHE GE90 MATRIX REQUIREMENTS

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

ACTION PLAN: SNECMA WORKING TEAM STRATEGY.

THE FIRST PRIORITY IS TO IMPROVE THE ALTERNATOR HARNESSES.

THE SECOND PRIORITY IS TO IMPROVE THE OTHER CORE HARNESSES WHICH ARE

SENSITIVE TO THE CHAFING .

A SOLUTION MUST BE FOUNDED TO IMPROVE THE HARNESSES IN PRODUCTION LINE.

A SOLUTION MUST BE PROPOSED TO PROTECT THE HARNESSES IN THE FIELD OR IN STOCK.

(essentially Alternator harnesses)

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ISSUE 002 novembre, 1999Patrick POTIGNON

Systems Engineering

SNECMA Proprietary

This document is Snecma ’s property, it may not be used, reproduced or transmitted without their approval .

GE90 Product Reliability TeamHP CORE HARNESS CABLES CHAFING

SCHEDULE:

1. ALTERNATOR HARNESSES IMPROVEMENT.

•POTENTIAL SOLUTIONS EVALUATION: 15 NOVEMBER 1999

• PROPOSED SOLUTIONS FOR:

-Production line harnesses & Harnesses in the field 26 NOVEMBER 1999

• TG3 PRESENTATION WITH VALIDATION PLAN: 15 DECEMBER 1999

2. OTHER CORE HARNESSES IMPROVEMENT.

• TG3 PRESENTATION FORECAST: MARCH 2000