NORDAIIII SERVICE BULLETIN 

EXHAUST· THRUST REVERSER· APPLICATION OF PRIMER TO ENGINE ATTACH FLANGE 

1. PLANNING INFORMATION 

A. Effectivity 

Airplane - Bombardier Learjet 40/45 Model 45. 

TR5045 Thrust Reverser Serial Numbers A30040001 through A30040550. 

Spares 

Not applicable 

B. Concurrent Requirements 

Bombardier Learjet Service Bulletin No. SB 40-78-03, or 

Bombardier Learjet Service Bulletin No. SB 45-78-09. 

C. Reason 

Corrosion was found on some engine attach flanges of the TR5045 Thrust Reversers installed on 

new configuration composite engine fan ducts. 

D. Description 

This service bulletin gives instructions to inspect the engine attach flange for corrosion, remove 

corrosion if necessary, and add primer to the forward surface of the engine attach flange to protect 

the surface from corrosion. If the inspection results defined in this service bulletin conclude that the 

material thickness of the engine attach flange is less than the minimum allowable thickness, then only 

a Bombardier Learjet approved service facility shall be used for repair. 

E. Compliance 

Refer to Bombardier Learjet Service Bulletin No. SB 40-78-03 or No. SB 45-78-09. 

F. Approval 

The changes presented in this service bulletin are in accordance with FAA approved certification 

data. 

G. Manpower 

Approximately 1.5 labor-hours for removal and inspection of one thrust reverser. 

Approximately 1.0 additional labor-hour for application of primer on one thrust reverser. 

Approximately 4.0 additional labor-hours for removal of one fixed afterbody. 

NOTE: The above estimate is provided only for general guidance in operator's modification 

planning. The estimate is only for direct labor performed by experienced personnel on an 

aircraft which has been placed in a maintenance status. Setup time, non-productive 

elapsed time, curing time, and administrative time are not included. 

© Copyrighted NORDAM 2012. This document is not to be released under the Freedom of Information Act. PROPRIETARY DATA. 

NOR DAM reserves all proprietary rights in the data furnished herein. Use of this document is restricted to conveyance of information to 

customers or vendors of NORDAM. This information shall not be released, disclosed, used or duplicated for procurement or manufacturing 

purposes without/he written permission of NORDAM. By accepting receipt and possession of this document, you acknowledge and agree 

to these regulations. 

THE NORDAM GROUP · NACELLEITHRUST REVERSER SYSTEMS DIVISION 

6911 N. WHIRLPOOL DRIVE · TULSA, OK 74117, USA 

Issued: January 17, 2012 5045 78-13 

Page 1 of 6 
NOR DAM SERVICE BULLETIN 

H. Weight and Balance 

No change. 

I. Electrical Load Data 

Not changed. 

J. Software Accomplishment Summary 

Not Applicable. 

K. References 

The following data was used to prepare this Service Bulletin. 

NORDAM Engineering Drawings: 

LJ7831009, "Ring Assy- Attach, Afterbody", Revision A, ADCN 6 

LJ7831102, "Attach Ring Assy- Afterbody, Fixed", Revision IR, ADCN 5 

SRP-10-005, "LJ7830101-1/-2/-3/-4/-5/-6 Thrust Reverser Assemblies & LJ7831101-1/-2/-5/ 

-6/-7/-8 Afterbody Assembly, Fixed", Revision IR 

Manuals: 

MM-104, Bombardier Learjet 45 Maintenance Manual, Revision 40 

MM-105, Bombardier Learjet 40 Maintenance Manual, Revision 8 

SRM-104, Bombardier Learjet 40 Series Structural Repair Manual, Revision 1 

NDI-104, Bombardier Learjet 40 Series Nondestructive Inspection Manual, Revision 10 

L. Other Publications Affected 

None. 

M. Interchangeability or lntermixability of Parts 

None. 

2. MATERIAL INFORMATION 

A. Material Price and Availability 

Refer to Bombardier Learjet Service Bulletin No. SB 40-78-03 or No. SB 45-78-09. 

B. Material Necessary for Each Aircraft 

None. 

C. Material Necessary for Each Spare 

None. 

Issued: January 17, 2012 5045 78-13 

NORDAM PROPRIETARY DATA. Copyright Tile NOROAM Group, Inc. 2012 ALL RIGHTS RESERVED. 

No portion of this document may be released under tl1e Freedom of Information Act or similar foreign law. 

Page 2 of 6 
NORDANI SERVICE BULLETIN 

D. Material and Tools Supplied by Service Centers 

NOTE: Equivalent equipment or materials can be used to replace items in the following table. 

Part No. 

Base: 1 OP4-2 

Hardener: EC-117S 

Thinner: TR-19 

Retarder Thinner: TR-20 

Thinner: MPK (Technical 

Grade Only) 

Base: 463-6-3 

Catalyst: X-306 

Thinner: TL-52 

Alodine 1200 

Abrasive Pads 

Abrasive Paper 

Methyl n-Propyl Ketone 

(MPK) 

Cloth Wipes 

E. Reidentified Parts 

None. 

F. Special Equipment 

Keyword 

Epoxy Primer 

(Alternate) 

Chemical Conversion 

Coating 

Scotch-Brite Pads (Very 

Fine) (Type A- Aluminum 

Oxide) 

180-Grit or Finer 

Solvent 

Cotton, Lint-Free 

Manufacturer 

Akzo Nobel Aerospace Coatings 

East Water Street 

Waukegan, IL 60085 

Akzo Nobel Aerospace Coatings 

Henkel Corporation 

32100 Stephenson Highway 

Madison Heights, Ml 48071 

3M Company 

3M Center Bldg. 

St. Paul, MN 55144 

Commercially Available 

Commercially Available 

Commercially Available 

Fluorescent penetrant kit including ultraviolet light - Reference Learjet 40 Series Nondestructive 

Inspection Manual, NDI-104, Part 8 Penetrant Inspection- General Section, Equipment List. 

3. ACCOMPLISHMENT INSTRUCTIONS 

A. Prepare Thrust Reverser for Maintenance 

(1) Remove thrust reverser and fixed afterbody assembly from aircraft (Ref. Learjet 45 

Maintenance Manual, MM-104, 78-31-00 Thrust Reverser Assembly- Removal/Installation or 

Learjet 40 Maintenance Manual, MM-105, 78-31-00 Thrust Reverser Assembly- Removal/ 

Installation). 

B. Inspect Engine Attach Flange 

(1 ) Do a fluorescent penetrant inspection to detect corrosion (Ref. Learjet 40 Series Nondestructive 

Inspection Manual, NDI-104, Part 8 Penetrant Inspection- General Information). 

(2) If corrosion is not found proceed to step 3.0. 

(3) If corrosion is found proceed to step 3.C. 

Issued: January 17, 2012 5045 78-13 

NOR DAM PROPRIETARY DATA. Copyrigt1t The NOR DAM Group, Inc. 2012 ALL RIGHTS RESERVED. 

No portion of this document may be released under the Freedom of Information Act or similar foreign law. 

Page 3 of 6 
NOR DAM SERVICE BULLETIN 

C. Remove Corrosion from Forward Surface of Engine Attach Flange 

CAUTION. THE ENGINE ATTACH FLANGE SHALL HAVE A MINIMUM THICKNESS OF 

0.1151NCH (2.92 MM) AFTER PERFORMING THE BLEND REPAIR OR THE 

ENGINE ATTACH FLANGE MAY REQUIRE REPLACEMENT DEPENDING ON THE 

FINAL DISPOSITION BY BOMBARDIER LEARJET AND NORDAM. 

(1) Remove only the necessary amount of metal to remove corrosion from surface using 180-grit 

or finer abrasive paper. 

(2) Surface blend area shall be a 20:1 blend ratio. 

(3) Do a fluorescent penetrant inspection of each blend repair area to detect any remaining 

corrosion (Ref. Learjet 40 Series Nondestructive Inspection Manual, NDI-1 04, Part 8 Penetrant 

Inspection -General Information). 

(4) If corrosion is still found, do steps 3.C.(1) through 3.C.(3) until all corrosion is removed. 

(5) Measure remaining material thickness using micrometer. 

(6) If the material thickness of a blend repair is less than the minimum allowable thickness (See 

Figure 1 ), please contact Bombardier Learjet Field Service for further disposition (Refer to 

Bombardier Learjet Service Bulletin No. SB 40-78-03 or No. SB 45-78-09 for contact 

information). The engine attach flange may require replacement depending on the final 

disposition of Bombardier Learjet and NORDAM. 

NOTE: If the inspection results defined in this service bulletin conclude that the material thickness 

of the engine attach flange is less than the minimum allowable thickness, then only a 

Bombardier Learjet approved service facility shall be used for repair. 

(7) If the material thickness of a blend repair is equal to or greater than the minimum allowable 

thickness after all corrosion is removed (See Figure 1 ). proceed to step 3.D. 

D. Apply Finishes to Forward Surface of Engine Attach Flange. 

(1) Apply Alodine 1200 on forward surface of engine attach flange (Ref. Learjet 40 Series Structural 

Repair Manual, SRM-104, 51-30-15 Chemical Film Treatment of Aluminum and/or Aluminum 

Alloy). 

WARNING. SOLVENT IS CLASSIFIED AS A HAZARDOUS MATERIAL WHICH MAY CAUSE 

INJURY OR ILLNESS IF NOT PROPERLY USED. THIS PRODUCT SHOULD BE 

USED ONLY IN ACCORDANCE WITH THE MANUFACTURER'S MATERIAL SAFETY 

DATA SHEET. 

(2) Clean forward surface of the engine attach flange using cloth wipes dampened in solvent. 

NOTE: Do not allow solvent to dry on surfaces and make sure solvent is prevented from entering 

faying surfaces. 

(3) Wipe forward surface of the engine attach flange using a clean, dry cloth before solvent 

evaporates. 

Issued: January 17, 2012 5045 78-13 

NORDAM PROPRIETARY DATA. Copyrig/1/ Tile NORDAM Group, Inc. 2012 ALL RIGHTS RESERVED. 

No portion of this document may be released under the Freedom of Information Act or similar foreign law. 

Page 4 of 6 
NORDAM SERVICE BULLETIN 

WARNING: EPOXY PRIMER IS CLASSIFIED AS A HAZARDOUS MATERIAL WHICH MAY 

CAUSE INJURY OR ILLNESS IF NOT PROPERLY USED. THIS PRODUCT SHOULD 

BE USED ONLY IN ACCORDANCE WITH THE MANUFACTURER'S MATERIAL 

SAFETY DATA SHEET. 

(4) Mix epoxy primer in accordance with the manufacturer's instructions. 

(5) Apply an even, uniform layer of epoxy primer using the overlapping stroke or cross-coat stroke 

methods on the engine attach flange. Obtain a layer thickness of 12.7- 22.9 fJ.m (0.0005-

0.0009 inch). 

(6) Allow epoxy primer to dry in accordance with the manufacturer's instructions. 

E. Return Thrust Reverser to Service 

(1) Install thrust reverser on aircraft (Ref. Learjet 45 Maintenance Manual, MM-1 04, 78-31-00 

Thrust Reverser Assembly- Removal/Installation or Learjet 40 Maintenance Manual, MM-1 05, 

78-31-00 Thrust Reverser Assembly - Removal/Installation). 

(2) Record in accordance with Federal Aviation Regulations or local governing authority that 

NORDAM Service Bulletin No. 5045 78-13 is incorporated. 

Issued: January 17, 2012 5045 78-13 

NORDAM PROPRIETARY DATA. Copyright The NORDAM Group, Inc. 2012 ALL RIGHTS RESERVED. 

No portion of this document may be released under t11e Freedom of Information Act or similar foreign law. 

Page 5 of 6 
NORDANI SERVICE BULLETIN 

0.1151NCH (2.92 mm) 

MINIMUM ALLOWABLE THICKNESS 

SECTION A-A 

SECTION 8-8 

Engine Attach Flange 

Figure 1 

5045 78-13-01 

Issued: January 17, 2012 5045 78-13 

NORDAM PROPRIETARY DATA. Copyright The NORDAM Group, Inc. 2012 ALL RIGHTS RESERVED. 

No portion of l11is document may be released under the Freedom of Information Act or similar foreign law. 

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