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S-92 ALERT 

SERVICE BULLETIN 

NOTICE TO ALL PERSONS RECEIVING THIS DOCUMENT: 

WARNING: THIS DOCUMENT, OR AN EMBODIMENT OF IT IN ANY MEDIA, DISCLOSES INFORMATION WHICH IS PROPRIETARY, IS THE PROPERTY OF SIKORSKY AIRCRAFT CORPORATION AND/OR ITS SUBSIDIARIES, IS 

AN UNPUBLISHED WORK PROTECTED UNDER APPLICABLE COPYRIGHT LAWS, AND IS DELIVERED ON THE EXPRESS CONDITION THAT IT IS NOT TO BE USED, DISCLOSED, REPRODUCED, IN WHOLE OR IN PART 

(INCLUDING REPRODUCTION AS A DERIVATIVE WORK), OR USED FOR MANUFACTURE FOR ANYONE OTHER THAN SIKORSKY AIRCRAFT CORPORATION AND/OR ITS SUBSIDIARIES WITHOUT ITS WRITTEN CONSENT,

AND THAT NO RIGHT IS GRANTED TO DISCLOSE OR SO USE ANY INFORMATION CONTAINED HEREIN. ALL RIGHTS RESERVED. ANY ACT IN VIOLATION OF APPLICABLE LAW MAY RESULT IN CIVIL AND CRIMINAL 

PENALTIES. 

EXPORT WARNING: THESE COMMODITIES, TECHNICAL DATA OR SOFTWARE ARE SUBJECT TO THE EXPORT CONTROL OF EITHER THE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS (ITAR) OR THE EXPORT 

ADMINISTRATION REGULATIONS (EAR) AND CANNOT BE EXPORTED WITHOUT THE PRIOR AUTHORIZATION OF EITHER THE DEPARTMENT OF STATE OR THE DEPARTMENT OF COMMERCE. THE TERM “EXPORT”

INCLUDES ANY DISCLOSURE AND/OR PROVISION OF ACCESS TO COMMODITIES, TECHNICAL DATA OR SOFTWARE TO OR BY FOREIGN NATIONALS (WHETHER LOCATED IN THE UNITED STATES OR ABROAD). THIS 

REQUIREMENT ALSO APPLIES TO FOREIGN NATIONAL EMPLOYEES OF U.S. COMPANIES AND THEIR FOREIGN SUBSIDIARIES. 

ASB 92-26-004 

Basic Issue ▪ June 04/12 

SUBJECT: FIRE PROTECTION – Engine and APU Fire Extinguishing Lines – Modification of No. 1 

Engine Forward Firewall Center Discharge Tube 

Section 1. PLANNING INFORMATION 

A. Effectivity S-92A model helicopters with serial numbers 920006 through 920169. 

B. Purpose To modify No. 1 engine forward firewall center discharge tube to correct length and 

position and to inspect outboard discharge tube for correct orientation. 

C. Description Center discharge tube is removed, modified and installed in correct orientation. 

Outboard discharge tube is visually inspected for correct orientation and 

repositioned if required. 

D. Compliance Compliance is essential. The instructions outlined herein shall be accomplished 

within 120 days from the issue date of this Alert Service Bulletin (ASB). 

E. Approval The design change effected by this document is classified as Major, and is FAA 

approved in accordance with the applicable requirements of United States Federal 

Aviation Regulations 14 CFR Part 29. FAA approval constitutes EASA and 

Transport Canada approval under the terms of current BAA/BASA Implementation 

Procedures. 

 

Sikorsky Aircraft Corporation

6900 Main Street P.O. Box 9729 

Stratford, Connecticut 06615-9129 

(203) 386-4000
S-92 ALERT ASB 92-26-004 

SERVICE BULLETIN Basic Issue ▪ June 04/12 

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Section 1. PLANNING lNFORMATION (Continued) 

F. Manpower (Estimated) 

Task No. of Men No. of Hours Man-Hours* 

Modify No. 1 engine forward firewall 

center discharge tube 

1 2.0 2.0 

Inspect outboard discharge tube 1 1.0 1.0

Total Man-Hours 3.0 

*Estimate does not include time required to prepare helicopter or return it to flight status. 

G. Material 

None. 

H. Tooling 

(1) Tubing cutter (commercial grade or equivalent). 

(2) Straight edge ruler (commercial grade or equivalent). 

(3) Digital caliper (commercial grade or equivalent). 

(4) Torque wrench 150-750 inch-lbs (commercial grade or equivalent). 

(5) Shorting jumper (commercial grade or equivalent). 

I. Weight and Balance 

Not affected. 

J. Electrical Load Data 

Not affected. 

K. Software Load Data 

Not changed. 

L. References 

(1) Maintenance Manual SA S92A-AMM-000, Chapter/Section 53-70-00-900-001. 

(2) Temporary Revision No. 26-03 against Maintenance Manual SA S92A-AMM-000, 

Chapter/Section 26-21-04-960-004, Removal/Installation of Engine Fire Extinguishing 

Lines - Engine Inlet, is issued concurrently with this ASB. 
ASB 92-26-004 S-92 ALERT

Basic Issue ▪ June 04/12 SERVICE BULLETIN

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Section 1. PLANNING lNFORMATION (Continued) 

M. Publications Affected 

Maintenance Manual SA S92A-AMM-000, Chapter/Section 26-21-04-960-004. 

N. Attachment 

None. 

Section 2. MATERIAL INFORMATION 

A. Basis for Material Data 

Per helicopter. 

B. Bill of Material 

None. 

C. Consumable Material 

Qty Nomenclature Part No. Source

As Req’d Anti-Seize Compound Never-Seez, NPBT-8, or equivalent (1) 

As Req’d Protective Caps and Plugs NAS847 or equivalent (2) 

As Req’d Permanent Marker Commercial grade or equivalent (3) 

(1) Available from Bostik, Inc. Website: www.bostik-us.com. 

(2) Available from CSG Parts. Website: http://www.csgparts.com/

(3) Procure through local supply. 

Section 3. ACCOMPLISHMENT INSTRUCTIONS 

A. Prepare helicopter for modification: 

(1) Turn off all helicopter electrical and hydraulic power. 

OBSERVE ALL CAUTIONS AND WARNINGS ON CONTAINERS 

WHEN USING CONSUMABLES. WHEN APPLICABLE, WEAR 

NECESSARY PROTECTIVE GEAR DURING HANDLING AND USE. IF 

A CONSUMABLE IS FLAMMABLE OR EXPLOSIVE, MAKE CERTAIN 

CONSUMABLE AND ITS VAPORS ARE KEPT AWAY FROM HEAT, 

SPARK AND FLAME. MAKE CERTAIN FIREFIGHTING EQUIPMENT 

IS READILY AVAILABLE PRIOR TO USE. FOR ADDITIONAL 

INFORMATION ON TOXICITY, FLASHPOINT AND FLAMMABILITY 

OF CHEMICALS, CONSULT YOUR MEDICAL PEOPLE OR THE 

MANUFACTURER OF THE CONSUMABLE. 
S-92 ALERT ASB 92-26-004 

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

(2) Engage rotor brake. 

(3) Open No. 1 engine cowling/work platform to access fire extinguishing lines. Refer to 

Maintenance Manual SA S92A-AMM-000, Chapter/Section 53-70-00-900-001. 

B. Modify No. 1 engine forward firewall center discharge tube: 

(1) Loosen B-nut on center discharge tube and remove tube from tee fitting. Install protective 

cap or plug on tee fitting. 

NOTE: Final length of center discharge tube shall be 4.0 inches long. 

(2) Using tubing cutter, cut 2.0 inches off discharge end of center discharge tube (Figure 1). 

(3) Deburr both OD and ID of cut end of center discharge tube. Blow tube clear with 

compressed air. 

(4) Using permanent marker (commercial grade or equivalent), reidentify center discharge 

tube (92310-04050-057) to 92310-04050-058. 

(5) Remove protective cap or plug from tee fitting. 

(6) Coat male threads with anti-seize compound (Never-Seez, NPBT-8, or equivalent). 

(7) Loosely install center discharge tube on tee fitting. Position tube as shown and torque Bnut to 285 inch-lbs. (Figure 2). 

C. Visually inspect outboard discharge tube for correct orientation as follows: 

(1) Verify orientation is to dimension shown (Figure 3) 

(a) If orientation is not correct proceed to section D. 

(b) If orientation is correct proceed to section E. 

D. Orient outboard discharge tube as follows: 

(1) Loosen clamp securing outboard discharge tube to firewall. 

(2) Loosen B-nut on outboard discharge tube. 

(3) Position outboard discharge tube to dimension shown and torque B-nut to 285 inch-lbs 

(Figure 3). 

(4) Tighten clamp securing outboard discharge tube to firewall. 
ASB 92-26-004 S-92 ALERT

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

E. Completion procedures: 

(1) Close No. 1 engine cowling/work platform. Refer to Maintenance Manual SA S92A-AMM000, Chapter/Section 53-70-00-900-001. 

(2) Return helicopter to service. 

F. Record of compliance: 

(1) Make helicopter logbook entries to show compliance with this ASB as follows: 

(a) Make helicopter level logbook entry on form SA7343-15. 

(b) When ASB modifies a component that can be removed from this helicopter: 

1. Make component log card entries on forms SA7343-22 & SA7343-21 as 

applicable. 

2. If a component modified by this ASB does not have a log card and the ASB 

does not create one, then annotate compliance on the next higher assembly 

that the component belongs to which does have a log card. 

NOTE: If access to www.Sikorsky360.com is unavailable, complete attached ALERT 

SERVICE BULLETIN COMPLIANCE RECORD CARD and return it to Sikorsky 

Aircraft Corporation. 

(2) Make an appropriate electronic compliance entry in the E-Notification section at 

www.Sikorsky360.com. Refer to User Guide located on the www.Sikorsky360.com/ENotification Search page. 
S-92 ALERT ASB 92-26-004 

SERVICE BULLETIN Basic Issue ▪ June 04/12 

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

CENTER DISCHARGE TUBE MODIFICATION 

FIGURE 1 

SA

TD2737_1

2.0 INCH

CENTER 

DISCHARGE TUBE
ASB 92-26-004 S-92 ALERT

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

CENTER DISCHARGE TUBE ORIENTATION 

FIGURE 2 (SHEET 1 OF 2) 

SA

TD2737_2 4.9 INCH

FORWARD 

FIREWALL

CENTER 

DISCHARGE TUBE

5.1 INCH
S-92 ALERT ASB 92-26-004 

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

CENTER DISCHARGE TUBE ORIENTATION 

FIGURE 2 (SHEET 2) 

TD2737_3SA

CENTER

DISCHARGE TUBE

APPROXIMATELY

0.3 INCH

CLEARANCE

APPROXIMATELY

0.3 INCH 

CLEARANCE

CENTER 

DISCHARGE TUBE

1.7 INCH

1.4 INCH

SEE NOTE

ENGINE OIL

FILTER

ENGINE OIL

FILTER

ENGINE OIL

PRESSURE TUBE

MEASUREMENT IS BETWEEN CENTER OF

NUT ON ENGINE OIL FILTER AND CENTER

OF CENTER DISCHARGE TUBE.

NOTE:
ASB 92-26-004 S-92 ALERT

Basic Issue ▪ June 04/12 SERVICE BULLETIN

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Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) 

OUTBOARD DISCHARGE TUBE ORIENTATION 

FIGURE 3 

2.0 INCH

1.8 INCH

FORWARD

FIREWALL

SA

TD2737_4

OUTBOARD

DISCHARGE

TUBE
(Fold over and tape closed) 

SIKORSKY AIRCRAFT CORPORATION 

FACSIMILE NUMBER (860) 998-7565 

EMAIL ADDRESS: GPSIKSASProductSafet@utc.com 

ATTENTION: SAS PRODUCT SAFETY MANAGER 

SIKORSKY AEROSPACE SERVICES 

(Fold Up to Arrows)

IMPORTANT NOTICE 

Upon COMPLIANCE with the attached ASB, Sikorsky requests your cooperation in completing and 

returning this ENTIRE PAGE by MAIL, FAX, or scan & EMAIL. 

If you have internet access, you may go to www.sikorsky.com to record your compliance. 

Please fill in the requested information at the bottom of the page, so we may maintain 

proper records documenting the configuration of your aircraft. This information is useful 

when determining configuration and effectivity of issues affecting fielded aircraft. 

This request is in keeping with our policy to assure that our customers receive the latest 

information applicable for the maintenance of your aircraft. Thank you. 

ALERT SERVICE BULLETIN: ________________ Compliance Record Card 

TITLE: ___________________________________________________________________ 

 ___________________________________________________________________ 

 ___________________________________________________________________ 

OWNER/OPERATOR: _____________________________________________________ 

SUBMITTED BY: ___________________________ DATE: ____________________ 

FOLLOWING SERIAL NUMBERS ARE NOT AFFECTED BY THIS ASB 

ASB HAS BEEN COMPLIED WITH ON THE FOLLOWING SERIAL NUMBERS 

 ___________ ___________ ___________ ___________ ___________ ___________ 

 ___________ ___________ ___________ ___________ ___________ ___________ 

ASB No. 92-26-004 

FIRE PROTECTION – Engine and APU Fire Extinguishing Lines – Modification of 

No. 1 Engine Forward Firewall Center Discharge Tube 
No Postage 

Necessary 

BUSINESS REPLY MAIL 

FIRST-CLASS MAIL PERMIT NO. 432 BRIDGEPORT CT 

POSTAGE WILL BE PAID BY ADDRESSEE 

SIKORSKY AIRCRAFT CORPORATION

P.O. BOX 9729 

6900 MAIN STREET 

STRATFORD, CONNECTICUT 06615-9129 U.S.A.

MAILSTOP: S328A

ATTENTION: SAS PRODUCT SAFETY MANAGER 

 SIKORSKY AEROSPACE SERVICES 

Please complete the form on the reverse side and FAX to 

FACSIMILE NUMBER (860) 998-7565 

Or scan and email to: 

EMAIL ADDRESS: GPSIKSASProductSafet@utc.com 

or fold and return ENTIRE form to Sikorsky Aircraft Corporation