# Bombardier Service Bulletin 45-57-13

Copy: Revision 1 ("Bombardier Learjet 45 Service Bulletin 45-57-13 Rev 1 dated October 26 2020"), 17 pages: PDF https://openairdocs.org/files/sha256/99/17/991761487fe683ac704812b48bab9a4f1f925dfb3383f396a0cca3536a74ea63; text https://openairdocs.org/service-documents/bombardier/sb-45-57-13/file/991761487fe6.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2021-0157; AD 2021-23-08 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Bombardier](https://openairdocs.org/service-documents/bombardier.md)
- Type: Service bulletin (Service Bulletin)
- Number: 45-57-13
- Latest revision known: 45-57-13, Revision 1, dated October 26, 2020 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/bombardier/sb-45-57-13

## ADs that cite it (1) (OpenAirDocs)

Newest first, with the revision each names, as OpenAirDocs read it from the AD's text.

- [AD 2021-23-08](https://openairdocs.org/ad/2021-23-08.md), effective Jan 10, 2022: Revision 1

Also cited in [1 proposed AD](https://openairdocs.org/service-documents/bombardier/sb-45-57-13/proposed.md).

## Text (17 pages)

Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2021-0157; AD 2021-23-08 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

2
THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
LEARJET 45
RT 45-57-13
Recommended
Revision Transmittal Sheet
RT 45-57-13
Page 1 of 2
Oct 26/2020
APPROVED IN WHITE
This page transmits Revision 1 to Service Bulletin No. 45-57-13, “Wing Spar Inspection.”
Rework:
No rework is required for aircraft which have complied with previous issues of this document.
Summary:
Updated Description; Compliance; Materials Required; Tools, Equ ipment and Materials; References;
revised Modification Instructions to provide more detailed insp ection and repair procedures, and added
Figures 1 and 2. 
NOTE: Change bars are placed in the left margin of pages where s ignificant changes are located. This
revision incorporates the latest document format for Learjet se rvice instructions. The general
arrangement of this document may change from the previous issue.
Description of Changes
In the Planning Information section:
Changed the Description information as follows:
Revised text to include all accompanying “structure”.
Changed the Compliance information as follows:
Changed the time compliance from “Bombardier Learjet Inc. recom mends these instructions are
completed within 12 months of service bulletin release for airc raft with more than 8 years time in
service from Certificate of Airw orthiness date.” to “The time c ompliance for this inspection is for
aircraft that are eight years fro m Certificate of Airworthiness . Aircraft with greater than eight years
from Certificate of Airworthiness have 12 months from February 25, 2019 to comply.”
Changed the Material Required information as follows:
Added step H.(2) Other materials/parts necessary to complete these instructions.
Changed the Tools, Equipment and Materials information as follows:
Added Learjet Non-Destructive Inspection Manual, Part 4 and Part 6, to the list.
Changed the References information as follows:
Added Learjet Maintenance Manual, Chapter 6 to the list of references.
Added Learjet Non-Destructive Inspection Manual, Part 4 and 6 to the list of references.

### Page 2

LEARJET 45
Revision Transmittal Sheet
THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
RT 45-57-13
Page 2 of 2
Oct 26/2020
In the Accomplishment Instructions section:
Changed the Gain Access information as follows:
Added maintenance manual references to steps A.(2) and (3).
Changed the Modification Instructions as follows:
Revised existing steps and added new steps to provide more detailed procedures to complete the
corrosion and protective treatments inspections and repairs. 
Deleted procedure step 3.B.(2). 
In the Illustrations section:
Added Figure 1, Sheets 1 to 4 for Wing Spar Inspection.
Added Figure 2, Sheet 1 for Corrosion Blending.
Filing Instructions:
This is a COMPLETE revision. Remove and discard all pages of th e prior issue and replace them with
pages of Revision 1. 
Record of Revisions:
ISSUE DISTRIBUTION DATE
Basic Feb 25/2019
Revision 1 Oct 26/2020

### Page 3

2
THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
Refer to applicable government agency regulations and requirements and make sure that the work described 
in this publication is performed in compliance with manufacturer’s recommendations and/or acceptable industry standards. 
This document is proprietary to Bombardier Inc. and/or its affiliates and may not be reproduced or copied in any form or by 
any means without the prior written consent of Bombardier Inc. and/or its affiliates. 
© 2019, Bombardier Inc. All rights reserved. 
Challenger*, Global Express*, Learjet*, are Trademarks of Bombardier Inc.
SB 45-57-13
Recommended
Page 1 of 11
Basic Issue: Feb 25/2019 
Revision 1: Oct 26/2020
Contact Information Distr ibution Date Rev. No.  
Business Aircraft 
Learjet Inc.
MS 53
P.O. Box 7707
Wichita, Kansas 67277-7707
Customer Response Center (CRC)
yul.parts@aero.bombardier.com 
1-866-538-1247 (Toll Free)
1-514-855-2999 (Tel)
October 26, 2020 1
LEARJET 45
If the instructions in this publication cannot be completed bec ause of an STC change to the aircraft, speak to
the STC holder or the regional Federal Aviation Administration (FAA) office for information and disposition.
Service Bulletin
These commodities, technology or software were exported from the United States in accordance
with the Export Administration Regulations. Diversion contrary to United States law is prohibited.
SB 45-57-13
Recommended
WINGS - WING SPAR INSPECTION
1. Planning Information
A. Effectivity
(1) Learjet 45-005 thru 45-367, 45-369 thru 45-445 and 45-447 thru 45-455.
B. Reason
(1) Corrosion has been observed on the lower wing splice plates that require a more frequent interval
to detect and correct any protective coatings.
C. Description 
(1) This service bulletin provides instructions to perform an in spection of the center wing area from
front spar to rear spar between wing stations 33.00L to 33.00R and all accompanying structure.

### Page 4

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 2 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
D. Compliance 
(1) Recommended - The time compliance for this inspection is for  aircraft that are eight years from
Certificate of Airworthiness. Aircraft with greater than eight years from Certificate of Airworthiness
have 12 months from February 25, 2019 to comply. 
E. Approval
(1) The Federal Aviation Administration (FAA) has approved the t echnical content in this publication
that has an effect on the airplane type design. 
(2) The European Aviation Safe ty Agency (EASA)  has accepted  the technical content in this
publication that has an effect on the airplane type design.
(3) Transport Canada Civil Aviation (TCCA) has accepted the technical content in this publication that
has an effect on the airplane type design. 
F. Labor Hours - Estimated Accomplishment Time
NOTE: The labor hours provided are estimates to assist schedulin g and planning the tasks given
in this bulletin. The estimates are for direct labor performed by an experienced crew and
do not include the time for familiarization, planning, aircraft preparation in hangar, such as
towing and positioning of scaffolds, removal of aircraft loose equipment, acquisition of
tools and equipment, training, supervision and inspection. 
If labor coverage is provided, only the hours above will be paid.
When planning to complete these instructions, please contact Bo mbardier Aerospace,
Learjet Inc. Business Aircraft C ustomer Service, Parts Services  for parts availability and
shipping times as necessary. (Refer to the title page of this d ocument for contact
information.)
G. Expense Coverage 
(1) None.
(2) Labor Coverage - None.
(3) Material Coverage - None.
(4) Smart Parts Plus Coverage
(a) None.
LABOR 
HOURS TASK
3.0 Labor hours to gain access.
1.0 Labor hours to do the aircraft modification.
3.4 Labor hours to return the ai rcraft to airworthy status.
7.4 Total Labor Hours

### Page 5

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 3 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
H. Material Required 
(1) There are no kits associated with these instructions.
(2) Other materials/parts necessary to complete these instructions.
NOTE: You can use equivalent a lternatives for these items.
For current prices, availability,  ordering and shipping informa tion, please call
Bombardier Aerospace, Learjet Inc. Business Aircraft Customer S ervice, Parts
Services. (Refer to the title page of this document for contact information.)
I. Tools, Equipment and Materials
(1) Refer to Part 4 of the Non-Destructive Inspection Manual , Ultrasonic Inspection - General
Information. 
(2) Refer to Part 6 of the Non-Destructive Inspection Manual , General Procedure for Inspection of
Surface Cracks on Aluminum Alloy Parts. 
J. Weight and Balance
(1) Negligible.
K. References
NOTE: If applicable, referenced third party documentation can be  accessed from the Customer
Portal under this service bulletin number.
(1) Service Bulletin Compliance Response Form.
(2) Service Bulletin Evaluation Sheet.
(3) Learjet Maintenance Manual, Chapters 6 and 24.
(4) Learjet Structural Repair Manual, Chapter 51.
(5) Learjet Non-Destructive Inspection Manual, Part 4 and 6.
2. Material Information
A. Parts Required
(1) There are no kits associated with these instructions. Refer to Paragraph 1.H. for more materials/
parts necessary to complete these instructions.
PART 
NUMBER NOMENCLATURE QTY SUPPLIER
240 Grit (or finer) 
Aluminum Oxide Abrasive Paper As Required Commercially Available
400 Grit 
Aluminum Oxide Abrasive Paper As Required Commercially Available
Methyl Propyl 
Ketone (MPK) Cleaning Solvent As Required Commercially Available

### Page 6

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 4 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
3. Accomplishment Instructions
A. Gain Access
(1) Set the battery switches to OFF. If necessary, disconnect ex ternal electrical power and the main
and emergency batteries from the aircraft. (Refer to Chapter 24 of the Maintenance Manual.)
(2) Remove panels 510AC, 510BC, 510BL, and 610BR. (Refer to Chapter 6 of the Maintenance Man-
ual.)
(3) Lower panels 510AL, 610AR, 720BL, and 730BR. (Refer to Chapter 6 of the Maintenance Man-
ual.)
B. Modification of Aircraft 
(1) Perform a visual inspection for corrosion or deterioration (cracked, chipped, peeling, or thining) of
protective treatments of the center wing area from front spar t o rear spar between wing stations
33.00L to 33.00R. (See Figure 1.)
(a) Do an inspection of the forward and aft sides of the front, mid, and rear center wing spars.
(b) Do an inspection of the left and right hand ribs at WS 5.8, WS 16.5, and WS 33.0.
(c) Do an inspection of the front, mid, and rear spar splice plates.
(d) Carefully examine the accompanying fasteners.
(2) Deleted.
(3) If no corrosion is found and the protective treatments are not deteriorated, go to step 3.B.(9).
(4) If no corrosion is found but the protective treatments are deteriorated:
(a) As necessary treat the deteriorated areas in accordance with  Chapter 51 of the Structural
Repair Manual, Revision 22 or later approved revision.
(b) After the protective treatments have been applied go to step 3.B.(9).
(5) If corrosion is found:
CAUTION: DO NOT REMOVE MORE THAN 50% OF THE FASTENERS AT ONE TIM E
WITHOUT SHORING THE WING.
(a) As necessary, remove fasteners to get access to the corrosion. 
1) Do not remove more than 50% of the fasteners at one time with out shoring the wing.
Contact the Learjet Customer Response Center for shoring procedures.
(b) Blend the corroded area as follows:
1) Blend the corrosion area with a minimum 10:1 blend ratio. (See Figure 2.)
CAUTION: DO NOT USE STEEL WOOL, S TEEL WIRE BRUSHES OR SEVERE
ABRASIVES WHEN YOU REWORK THE STRUCTURE FOR CORROSION.
USE 240 GRIT OR FINER ALUMINUM OXIDE ABRASIVE PAPER. FINISH
WITH 400 GRIT PAPER.
2) Get the necessary tools and equipment.
3) Clean the corroded area so that all loose corrosion and debris is removed from the rework
areas.
4) Use 240 grit and then progressively finer grit aluminum oxide abrasive paper to sand and
blend the corroded areas to get the specified surface finish. (See Figure 2.)

### Page 7

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 5 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
WARNING: SPECIAL PRECAUTIONS MUST BE OBSERVED DURING CLEANING.
CLEANING SOLVENTS ARE TOXIC AND FLAMMABLE. YOU MUST
WEAR PROTECTIVE MASK AND SUPPLY SUFFICIENT VENTILATION
WHEN YOU USE THE CLEANING SOLVENTS.
YOU MUST FOLLOW THE MANUFACTURER’S PUBLISHED
INSTRUCTIONS WHEN YOU USE CLEANING SOLVENTS.
5) With a clean cloth soaked with cleaning solvent (MPK), clean the sanded surface. 
a) Immediately wipe the area dry with a clean, dry cloth.
b) Do not let the cleaning solvent be “wicked” under the adjacent structure.
6) Make sure to keep a RMS 63 finish or better.
(c) Do an eddy current inspection of the blended areas as follows:
NOTE: This inspection is to make sure the corrosion is removed.
1) Complete the eddy current inspections in accordance with Lear jet NDI-104 manual, Part
6, Eddy Current Inspection (General) and Part 6, 51-00-01, Gene ral Procedure for
Inspection of Surface Cracks on Aluminum Alloy Parts, Revision 23 or later approved
revision.
2) All NDI analysis must be done by an NAS 410 or ANST equivalen t minimum level II
inspector qualified to the specific methodology.
(d) If corrosion is found during the eddy current inspection:
1) Do the blending procedures again in accordance with step (b) above.
2) Do the eddy current inspection again on the new blended areas  in accordance with step
(c) above.
(6) Do the ultrasonic thickness measurements as follows:
(a) Lay out the 0.5 by 0.5 inch grids for the ultrasonic thickne ss measurements over the blended
areas that extend to undamaged material. (See Figure 1, Details B, C, D and associated views
for typical examples.)
NOTE: The spar flange tapers in both the inboard/outboard and fo rward/aft directions.
Document the position of the grid for the ultrasonic thickness measurements with
two dimensions to key spar features. Complete the ultrasonic me asurements
square to the X axis. [The X axis is the monument lines (webs, corners, etc.) that
are parallel to the aircraft centerline.] 
(b) Do the ultrasonic thickness measurements within each grid ar ea in accordance with Learjet
NDI-104 manual, Part 4, Ultrasonic Inspection, and ASTM standar ds, ASTM E797/E797M
Standard Practice for Measuring Thickness by Manual Ultrasonic Pulse-Echo Contact
Method, as follows:
1) All NDI analysis must be done by an NAS 410 or ANST equivalen t minimum level II
inspector qualified to the specific methodology.
2) To capture the taper thickness, make sure to measure at least  two locations within the
blended area. 
3) Make sure the measurements are taken where the most material was removed.
4) Extend the ultrasonic measurements two grid points past the blended area minimum.
(c) Give the results of the ultrasonic measurements, with digital photos of all blended areas, to the
Learjet Customer Response Center for analysis by Customer Suppo rt Engineering of the
blended area remaining material thickness.
(d) Do not proceed until approval has been received from Learjet  Customer Support Engineering
for all corrosion repairs.

### Page 8

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 6 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
(7) After engineering approval of the corrosion repair, apply th e protective treatment to all repaired
and deteriorated areas in accordance with Chapter 51 of the Structural Repair Manual , Revision
22 or later approved revision.
(8) Replace all removed hardware with new hardware in accordance with Chapter 51 of the Structural
Repair Manual, Revision 22 or later approved revision. 
NOTE: You can procure all new hard ware locally or contact Learjet Spare Parts Sales.
(a) If necessary, remove the wing shoring.
(9) Install equipment removed for inspection or repair.
(10) Install panels 510AC, 510BC, 510BL, and 610BR. (Refer to Chapter 6 of the Maintenance Man-
ual.)
(11) Close panels 510AL, 610AR, 720BL, and 730BR. (Refer to Chapter 6 of the Maintenance Man-
ual.)
C. Return Aircraft to Airworthy Status
(1) Connect the main and emergency  batteries to the aircraft. (R efer to Chapter 24 of the Mainte-
nance Manual.)
(2) Install any additional items removed for access.
D. Compliance Response Form
(1) Complete the compliance response form.
(2) Send the compliance response form to Learjet Inc. as soon as possible.
E. Aircraft Maintenance Records 
(1) Complete the Aircraft Maintenance Records in accordance with the regulatory requirements of the
appropriate aircraft certification authority.

### Page 9

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 7 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
Wing Spar Inspection
Figure 1 (Sheet 1 of 4)
K75-755701-001-01
C
Detail A
A
D
B
CENTER WING STRUCTURE
SKIN AND ASSOCIATED EQUIPMENT NOT SHOWN FOR CLARITY

### Page 10

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 8 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
Wing Spar Inspection
Figure 1 (Sheet 2 of 4)
K75-755701-001-02
F
F
E
E
G
G
Detail D
Detail C
Detail B
REAR SPAR
CENTER WING
4557100019
MID SPAR
CENTER WING
4557100018
MID SPAR - LH SHOWN
H
H
FRONT SPAR
CENTER WING
4557100017
REAR SPAR
FRONT SPAR

### Page 11

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 9 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
Wing Spar Inspection
Figure 1 (Sheet 3 of 4)
K75-755701-001-03
0.50 x 0.50 in GRID
1
1
Typical blended areas.
NOTE
1
BL
0.00
BL
5.80
BL
5.80
View E-E
VEW LOOKING AFT
FRONT SPAR GRID
LH OUTBD
UP
FRONT SPAR
CENTER WING
4557100017
11
0.50 x 0.50 in GRID
FRONT SPAR
CENTER WING
4557100017
BL
0.00
BL
5.80
BL
5.80
View F-F
VEW LOOKING DOWN ON LOWER FLANGE
FRONT SPAR GRID
LH OUTBD
FWD

### Page 12

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 10 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
Wing Spar Inspection
Figure 1 (Sheet 4 of 4)
K75-755701-001-04
Typical blended areas.
NOTE
1
View G-G
VEW LOOKING DOWN ON LOWER FLANGE
MID SPAR GRID - LH SHOWN
LH OUTBD
FWD
0.50 x 0.50 in GRID
1BL
0.00
BL
5.80
MID SPAR
CENTER WING
4557100018
View H-H
VEW LOOKING DOWN ON LOWER FLANGE
REAR SPAR GRID
0.50 x 0.50 in GRID1 15 PLACES 1
1
BL
5.80
BL
0.00
BL
5.80
BL
11.28
BL
11.28
RH OUTBD
FWD
REAR SPAR
CENTER WING
4557100019

### Page 13

THIS PUBLICATION IS AVAILABLE AT:
https://my.businessaircraft.bombardier.com
SB 45-57-13
Recommended
Page 11 of 11
Basic Issue: Feb 25/2019
Revision 1: Oct 26/2020
LEARJET 45
Service Bulletin
Corrosion Blending
Figure 2 (Sheet 1 of 1)
LONGITUDINAL
K75-755701-002-01
CORROSION DAMAGE BEFORE REWORK
DEPRESSION AFTER CORROSION REMOVAL
(ROUGH EDGES HAVE BEEN SMOOTHED AND
ALL CORROSION HAS BEEN REMOVED)
DISH-OUT AFTER BLENDING
(BLENDING HAS BEEN ACCOMPLISHED IN THE
RATIO SPECIFIED AND DIRECTION SHOWN)

### Page 14

SERVICE BULLETIN COMPLIANCE RESPONSE
It is necessary that Bombardier Learjet record aircraft having complied with
this Service Bulletin. Please fill in the Service Bulletin and aircraft information
below, sign and date the form in the space provided, fold on dotted lines, seal
with tape, and mail completed form to Bombardier Learjet Maintenance Engi-
neering. If mailed within the United States, this form may be mailed to Bom-
bardier Learjet Maintenance Engineering using business reply mail (see
reverse). This form may be faxed or emailed if preferred. (See mailing infor-
mation provided.)
WARRANTY - Completion of this response form is required in order to pro-
cess the warranty claim. Therefore, if a warranty allowance is provided in the
Service Bulletin, return a copy of this form with the warranty claim.
SMART PARTS - Completion of this response form is required in order to
remain, enroll, or re-enroll in the Smart Parts Program.
*An email will be opened addressed to 
Fracas and this form will be attached.
Mailing Information:
Bombardier Learjet
Maintenance Engineering
(MS #78) (FAX 316 946-2305)
fracas_usa@aero.bombardier.com
Customer Support
Learjet, Inc.
CLICK HERE TO EMAIL
Service Bulletin Information
SB Title: ___________________________________________________________________________________
Service Bulletin No. _______________________ Rev No. ____________ Date ________________________
Aircraft Information
Model _____________ Serial No. _____________ Flight Hours _______________ Landings ______________
Service Facility Information
Facility Incorporating Bulletin ___________________________________________________________________
Compliance Information
The above referenced Service Bulletin was complied with on the referenced serial number aircraft at the listed air-
craft flight hours/landings:
Actual hours to accomplish Service Bulletin: Acce ss _______ Modify_______ Test(s) _______ Restore ________
Name: (Please Print) ______________________________________________ Date _____________________
Email: __________________________________________________________
Comments

### Page 15

FOLD HERE LAST. SEAL WITH TAPE. DO NOT STAPLE.
ATTN: MAINTENANCE ENGINEERING (MS NO. 78)
LEARJET INC
PO BOX 7707
WICHITA, KS 67277-9801
POSTAGE WILL BE PAID BY ADDRESSEE
BUSINESS REPLY MAIL
PERMIT NO. 2928 WICHITA, KSFIRST-CLASS MAIL
FOLD HERE FIRST
NO POSTAGE
NECESSARY
IF MAILED
IN THE
UNITED STATES

### Page 16

UPON COMPLETION OF THE EVALUATION FORM, YOU MAY FOLD AND RETURN TO ADDRESS ON THE
REVERSE SIDE OR USE THE SUBMIT BUTTON AT THE TOP TO EMAIL IT.
SERVICE BULLETIN EVALUATION SHEET
YOUR COMMENTS WILL HELP US IMPROVE
OUR SERVICE BULLETINS
*An email will be opened addressed to the 
SB Group and this form will be attached.
CLICK HERE TO EMAIL
SERVICE BULLETIN: ____________________ REVISION: _________ DATED: ________________________
TITLE: ____________________________________________________________________________________
Actual hours to accomplish Service Bulletin: Access : ______ Modify: _______ Test(s): ______ Restore: _______
PLEASE SUPPLY THE FOLLOWING: NAME: _____________________________________________
OPERATOR: ___________________________________ EMAIL: ____________________________________
AIRCRAFT: _________________________________________ TELEPHONE:  _________________________
POOR FAIR GOOD VERY 
GOOD
EXCELLENT
HOW EASY IS THE BULLETIN TO UNDERSTAND?
COMMENTS
DOES THE BULLETIN TELL YOU ALL YOU NEED TO KNOW 
ABOUT THE JOB?
COMMENTS
DO YOU THINK THE BULLETIN CONVEYS THE BEST WAY 
TO DO THE JOB?
COMMENTS
HOW REALISTIC ARE THE LABOR-HOUR ESTIMATES?
COMMENTS
WHAT IS YOUR APPRECIATION OF THE ILLUSTRATION(S)?
COMMENTS

### Page 17

FOLD HERE LAST. SEAL WITH TAPE. DO NOT STAPLE.
ATTN: TECHNICAL PUBLICATIONS (MS NO. 53)
LEARJET INC
PO BOX 7707
WICHITA, KS 67277-9801
POSTAGE WILL BE PAID BY ADDRESSEE
BUSINESS REPLY MAIL
PERMIT NO. 2928 WICHITA, KSFIRST-CLASS MAIL
FOLD HERE FIRST
NO POSTAGE
NECESSARY
IF MAILED
IN THE
UNITED STATES

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.