Service Bulletin No: 24-009 Ref No: 151

Modification No: INSPECTION ATA Chapter: 24

SERVICE BULLETIN

PILATUS AIRCRAFT LTD. STANS, SWITZERLAND

Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 1 of 10

ELECTRICAL POWER - GENERAL

INSPECTION FOR CHAFING ON AN ELECTRICAL HARNESS IN THE ENGINE COMPARTMENT 

1. Planning Information

A. Effectivity

PC-7 Aircraft MSN 101 thru 618.

B. Concurrent Requirements

None.

C. Reason

(1) Problem

An operator has reported signs of chafing on a wiring harness attached to the engine 

mounting frame on the RH side of the engine compartment. If an electrical cable becomes 

chafed through the insulation, a short circuit could cause a fire in the engine compartment.

(2) Cause

The RH flexible duct for the condenser unit can chafe against the wiring harness.

(3) Solution

Do an inspection of the wiring harness, and the flexible duct, for damage. If major damage 

is found, replace parts as necessary. If minor chafing damage is found, install a protective 

sleeve on the wiring harness.

D. Description

This Service Bulletin gives the data and instructions necessary to examine the wiring harness 

and flexible duct for chafing, and replace or repair as necessary.

E. Compliance

Mandatory.

Accomplishment required not later than 90 days after the issue date of this Service Bulletin.

F. Approval

The technical content of this Service Bulletin is approved under the authority of Letter of DOA 

Acceptance ref. FOCA.21J.002.

Pilatus advises Operators/Owners to check with their designated Airworthiness Authorities for 

any changes, local regulations or sanctions that may affect the embodiment of this Service 

Bulletin.
Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 2 of 10

SERVICE BULLETIN

G. Copyright Information

© Pilatus Aircraft Ltd. This document contains proprietary information that is protected by 

copyright. All rights are reserved. No part of this document may be copied, reproduced or 

translated to other languages without the prior written consent of Pilatus Aircraft Ltd.

H. Manpower 

I. Weight and Balance

(1) Weight Change

None.

(2) Moment Change

None.

J. Electrical Load Data

Not changed.

K. Software

Not changed.

L. References

Aircraft Maintenance Manual (AMM): 12-00-00, 20-31-00.

Aircraft Parts Catalog (IPC): 21-50-02.

M. Publications Affected

None.

N. Interchangeability of Parts

Not applicable.

Man-Hours

(No replacement 

required)

Man-Hours

(Replacement 

required)

Preparation 1.0 1.0

Inspection 1.0 1.0

Replacement of Cables - 8.0

Repair (Installation of Protective Sleeve) 1.0 -

Installation 1.0 1.0

Close up 1.0 1.0

TOTAL MAN-HOURS 5.0 12.0
SERVICE BULLETIN

Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 3 of 10

2. Material Information

A. Material - Price and Availability

No modification kit is necessary to do this Service Bulletin.

Operators who require further information on price and availability should contact their Customer 

Liaison Manager at Pilatus Aircraft Ltd., 6371 Stans, Switzerland.

Operators are requested to advise Pilatus Aircraft Ltd, using the Service Bulletin Evaluation 

Sheet, of the Manufacturer’s Serial Number (MSN) and the flying hours of aircraft which are 

allocated for this Service Bulletin.

B. Material Necessary for Each Aircraft

(1) Operator Supplied Materials (Ref. AMM 20-31-00-00)

NOTE: Pilatus P/Ns are given for materials not included in AMM 20-31-00 at the time of 

Service Bulletin approval.

C. Material Necessary for Each Spare

None.

D. Re-identified Parts

None.

E. Tooling - Cost and Availability

Not applicable.

MATERIAL/

PART NO.

DESCRIPTION QTY REMARKS

P01-011 SOLVENT, ISOPROPYL 

ALCOHOL

A/R

P02-031 ABSORBENT PAPER A/R

P09-004 KOROSEAL BINDING A/R

P09-020 TAPE, GLASS FIBER A/R If required

P09-017 CABLE TIES, HEAT-RESISTANT A/R If required

917.96.92.154 PROTECTIVE SLEEVE A/R If required
Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 4 of 10

SERVICE BULLETIN

3. Accomplishment Instructions

WARNING: BE CAREFUL WHEN YOU USE THE CONSUMABLE MATERIALS. THEY ARE 

DANGEROUS AND CAN CAUSE INJURY. ALWAYS OBEY THE MANUFACTURERS 

HEALTH AND SAFETY INSTRUCTIONS.

A. Preparation

Open the engine cowlings (access panels ENG 3L and ENG 3R) (Ref. AMM 12-00-00, Page 

Block 1).

B. Inspection (Ref. Fig. 1)

(1) Loosen the hose clamp at one end of the flexible duct.

NOTE: You can do this at the end that is most easy for access.

(2) Disconnect and move the flexible duct away from the inspection area.

NOTE: The flexible duct installation is shown in IPC 21-50-02, Fig. 02.

(3) Do a visual inspection of the flexible duct for chafing damage. If you find damage that 

makes the flexible duct unserviceable, remove and discard the flexible duct.

(4) Use absorbent paper (Material No. P02-031) made moist with solvent (Material No. P01-

011) to clean the harness in the area to be inspected.

(5) Use a bright light source and mirror to do a visual inspection of the harness for chafing 

damage.

(6) If you find chafing on the harness and you can see bare wires under the insulation you 

must replace the damaged electrical cable(s):

(a) Send details/photographs of the damaged cable(s) to this address to get 

replacement data:

PILATUS AIRCRAFT LTD.,

Customer Technical Support (MCC),

P.O. Box 992,

6371 Stans, Switzerland

Fax: + 41 (0)41 619 67 73

Email: Techsupport@pilatus-aircraft.com

(b) After replacement of the damaged cable(s), continue with the procedure given in 

Para D, Installation.

(7) If you find chafing on the harness but you cannot see bare wires under the insulation, 

continue with the procedure given in Para C, Repair.

(8) If you find no chafing continue with the procedure given in Para D, Installation.
SERVICE BULLETIN

Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 5 of 10

C. Repair (Ref. Fig. 2)

(1) Remove the harness clamps and move the harness away from the engine mounting 

frame.

(2) Use absorbent paper (Material No. P02-031) made moist with solvent (Material No. P01-

011) to clean the harness where you will install the protective sleeve.

(3) Make sure there are no cable ties around the harness where the protective sleeve is to be 

installed. Remove cable ties as necessary.

(4) Cut a piece of the protective sleeve (P/N 917.96.92.154) long enough to cover the chafed 

area plus an additional 45 mm (1.75 in.) at each end. When you cut the protective sleeve:

(a) Use sharp scissors to cut the sleeve to the correct length. Make sure the cut is 

straight.

(b) Pull all loose fibers away from the cut end(s) with your fingers and then remove the 

fibers with scissors.

(c) Make sure no more fibers can come loose.

(5) Wrap glass fiber tape (Material No. P09-020) around the harness at the ends of the repair 

area (as shown on Figure 2).

(6) Fold 20 mm (0.75 in.) at the two ends of the protective sleeve inwards to make a double 

layer.

(7) Wrap the protective sleeve around the harness with the doubled ends located over the 

glass fiber tape.

(8) Install a cable tie (Material No. P09-017) at the ends of the protective sleeve to hold it in 

place.

(9) If necessary, install additional cable ties (Material No. P09-017) on the harness. You can 

install cable ties over the protective sleeve if required.

(10) Install the harness clamps to attach the harness to the engine mounting frame.

D. Installation (Ref. Fig. 1)

(1) Install the flexible duct and tighten the hose clamp(s).

NOTE: The flexible duct installation is shown in IPC 21-50-02, Fig. 02.

(2) Use Koroseal binding (Material No. P09-004), as required, to secure the flexible duct to 

the engine mounting frame. Do this to prevent movement of the flexible duct which could 

cause chafing.

E. Job Close-Up

(1) Remove all equipment, materials and tools from the work area. Make sure that the work 

area is clean.

(2) Close the engine cowlings (access panels ENG 3L and ENG 3R).
Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 6 of 10

SERVICE BULLETIN

F. Documentation

(1) Make an entry in the Aircraft Logbook that this Service Bulletin has been incorporated.

(2) Use the Service Bulletin Evaluation Sheet and report your results and the serial number of 

the aircraft to PILATUS.
SERVICE BULLETIN

Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 7 of 10

Inspection

Figure 1

SB 2360

A

A

INSPECTION

AREA

WIRING HARNESS

FLEXIBLE DUCT
Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 8 of 10

SERVICE BULLETIN

Repair

Figure 2

SB 2361

CABLE TIE

20 mm

PROTECTIVE

SLEEVE

TAPE HARNESS
SERVICE BULLETIN

Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 9 of 10

SERVICE BULLETIN EVALUATION SHEET FOR SB No. 24-009

Title

Electrical Power - General

Inspection for Chafing on an Electrical Harness in the Engine 

Compartment 

Customer

Service Center

EMBODIMENT REPORTING

This SB has been embodied: On the entire fleet

Only partially

Provide embodiment details per aircraft (use additional copies of this table, if necessary)

MSN Flying Hours MSN Flying Hours

Additional embodiment comments/findings

EDITORIAL COMMENTS

 (procedure, kit quality, suggested improvements, etc.)

Name Signature Date

Please complete and forward this form to:

Pilatus Aircraft LTD,

Customer Technical Support (MCC),

P.O. BOX 992,

6371 Stans, Switzerland

Fax: +41 (0)41 619 6773

Email: Techsupport@pilatus-aircraft.com

SERVICE BULLETIN EVALUATION SHEET
Service Bulletin No: 24-009 Date: Sep 06/13

Rev. No. Date: Page 10 of 10

SERVICE BULLETIN

INTENTIONALLY BLANK