# 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 Seria l 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 inspec t 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 th e inspection results defined in this se rvice bulletin conclude that the material thickness of the en gine attach flange is less than the minimum allowab le thickness , then on ly a Bombardier Learjet approved service facility shall be used for repair . E . Complian ce 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 Inf ormation Act. PROPRIETARY DATA. NORDAM reserves all proprietary rights in the data furnished herein. Use of this document is restricted to conveyance of information to customers or vendors ofNORDAM. This information shall not be released, disclosed, used or duplicated forprocurement or manufacturing purposes without/he written permission ofNORDAM . By accepting receipt andpossession ofthis document, you acknowledge and agree to these regulations. THE NORDAM GROUP · NACELLE I THRUST REVERSER SYSTEMS DIVISION 69 11 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 Ba lance No change. 

### I. Electrical Load Data Not changed. J. Software Accomp l ishment Summary Not Applicable. K . References The following data was used to prepare this Service Bulletin . N ORDAM E ng i neering Drawings: LJ7831009 , " Ring Assy- Attach , Afterbody", Revision A , ADCN 6 LJ7831102 , "Attach Ring Assy- Afterbody, Fixed ", Revis ion 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 Lea r jet 45 Mai ntenan ce Manual , Revi sion 4 0 MM-105 , Bombardier Learj et 40 Maintenance Manual , Revision 8 SRM-104 , Bombardier Learjet 40 Series Structural Repair Manual , Revision 1 NDI-104 , Bombard ier Learjet 40 Series Nondestructive Inspection Manual , Revision 10 L. Other Publications Affected None. M . Interchangeability or l ntermixability of Parts None . 

### 2. MATERIA L INFORMATI ON A . Material Price and Availability Refer to Bombardier Learjet Service Bulletin No . SB 40-78-03 or No. SB 45-78-09 . B. Materia l Necessary for Each Airc raft 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 BUL L ETIN 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: 1OP4-2 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 Manua l , NDI-104, Part 8 Penetrant Inspection- General Section, Equipment List. 

### 3. ACCO MPLI SH ME NT IN STR UCTI O NS 

### 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 Assemb ly- Removal/Installation or Learjet 40 Mai ntenance Manual, MM-105, 78-31-00 Th rust Reverser Assembly- Removal/ Installation). B . Inspect Engine Attach Flange (1 ) Do a fl uorescent 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 NORDAM PROPRIETARY DATA. Copy rigt1t The NORDAM Gr o up, Inc. 2012 ALL RIGHTS RESERVED. No port ion of this document may be r eleased und er the Fre edom of I nf

or

mation Act or si mil

ar f orei gn law . 

### Page 3 of 6

# NOR DAM SERVICE BULLET IN 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 Manua l , 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 equa l to or greater than the minimum allowab le 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 port ion of th i s document m ay be released under the Freedom of Information Act or si milar fore i gn la w. 

### Page 4 of 6

# NORDAM SERVICE BUL L ETIN 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 i n 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 l ayer thickness of 12.7- 22 . 9 fJ.m (0 . 0005- 0 .0009 inch). (6 ) Allow epoxy primer to dry in accordance with the manufacture r 's instructions. E. Return Thrust Reverser to Service ( 1 ) Install thrust reverser on aircraft (Ref. Learjet 45 Maintenance Manua l , 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). (2) Record in accordance with Federal Aviation Regulations or local governing authority that NORDAM Service Bulletin No . 5045 78-13 is incorporated.

Issu ed: January 17 , 2012 

# 5045 78-13 NORD AM PR OP RIETARY DATA. Copyright The N O RDAM Grou p , Inc. 201 2 A LL RIGHTS R ESE RV ED . No portion of this document may be released under t11e Freedom of In f ormat ion 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 ofl11is document may be released under th e Freedom of Information Act or similar foreign law . Page 6 of 6