# MHI RJ Service Bulletin 601R-54-006

Copy: Revision A ("601R-54-006A - Released"), 16 pages: PDF https://openairdocs.org/files/sha256/e7/c8/e7c84d745c55b4fce666efc4e4e1204e26ca629e0272fa4537cd68cd5680dcc7; text https://openairdocs.org/service-documents/bombardier/601r-54-006/file/e7c84d745c55.md. Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2023-1404; AD 2023-21-12 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Bombardier](https://openairdocs.org/service-documents/bombardier.md) (issued as MHI RJ)
- Type: Service bulletin (Service Bulletin)
- Number: 601R-54-006
- Latest revision known: 601R-54-006, Revision A, dated May 24, 2023 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/bombardier/601r-54-006

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

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

- [AD 2023-21-12](https://openairdocs.org/ad/2023-21-12.md), effective Dec 26, 2023: Revision A

Also cited in [1 proposed AD](https://openairdocs.org/service-documents/bombardier/601r-54-006/proposed.md).

## Text (16 pages)

Rights: © Bombardier Inc. Filed by the FAA in regulations.gov docket FAA-2023-1404; AD 2023-21-12 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

SB 601R-54-006
Page 1 of 1
May 24/2023
SERVICE BULLETIN
REVISION TRANSMITTAL SHEET
SERVICE BULLETIN 601R-54-006
SUBJECT:  Nacelle/Pylons - Spars and Firewall - Inspection of Pylons Structure at
Fuselage Station 654.50 and 672.20
This page transmits:
Revision A of Service Bulletin 601R-54-006, dated May 24/2023.
The changes in this revision have no effect on aircraft that have had
this service bulletin incorporated.
Reason:
Revised Planning Information, paragraph 1., to:
Add in the Description section that the damage report form needs to be filled and sent
only if damage is found.
Change the revision level of one document in the References section.
Revised Accomplishment Instructions, paragraph 2., to:
Add information to clarify that a damage report form is to be completed only if
damage is found.
Remove a note that is no longer applicable.
This revision also includes small editorial changes that do not have an effect on the technical
content.
Instructions:  
Discard the copy of Service Bulletin 601R-54-006, dated Sep 13/2022. Replace with
the copy attached.
Service Bulletin History:  
Initial issue, dated Sep 13/2022
1

### Page 2

SB 601R-54-006
Page 1 of 15
Sep 13/2022
Revision A, May 24/2023
SERVICE BULLETIN
Technical
Publications
THIS SERVICE BULLETIN IS SENT TO EACH OPERATOR. IF THE OPERATOR HAS LEASED AIRCRAFT ,
TRANSFERRED SPARES IN THE LAST SIX MONTHS, SEND THIS SERVICE BULLETIN TO THE NEW
OWNER, UNLESS CONFIRMATION WAS RECEIVED THAT MHIRJ HAS INCLUDED THE NEW
OPERATOR ON THE DISTRIBUTION LIST .
SEND THIS SERVICE BULLETIN TO THE LESSEE. IF THE OPERATOR HAS SOLD AIRCRAFT OR
ATA SYSTEM: 54-50 NUMBER: 601R-54-006
SUBJECT:  Nacelle/Pylons - Spars and Firewall - Inspection of Pylons Structure at
Fuselage Station 654.50 and 672.20
1. PLANNING INFORMATION
A. Effectivity
Service Bulletin: CL-600-2B19 CRJ Series aircraft with serial numbers
7031, 7045, 7069, 7078, 7089, 7102, 7110, 7168, 7188,
7203, 7212, 7217,7229, 7231, 7236, 7243, 7257, 7258, 7269,
7271, 7276, 7284, 7290, 7302, 7304, 7306, 7310, 7328,
7339, 7342, 7355, 7358, 7360, 7401, 7404, 7437, 7441,
7448, 7458, 7474, 7476, 7479, 7495, 7502, 7503, 7517,
7527, 7530, 7532, 7548, 7551, 7574, 7575, 7579, 7582,
7586, 7588, 7599, 7600, 7606, 7609, 7623, 7632, 7648,
7657, 7658, 7664, 7667, 7674, 7681 thru 7683, 7687, 7715,
7727, 7743, 7748 thru 7750, 7758, 7760, 7769, 7780, 7810,
7817, 7818, 7821, 7822, 7857, 7859, 7871, 7873, 7889,
7892, 7895, 7909, 7912, 7913, 7920, 7922, 7923, 7926,
7929, 7932, 7935, 7937, 7954, 7961, 7964 and 8011.
Production: There is no production effectivity.
NOTE: The instructions in this service bulletin are only applicable to the
systems and parts installed at the time of delivery of the aircraft or as
changed by MHIRJ service bulletins. Before you do this service
bulletin, examine all Supplemental Type Certificates (STCs), and
Supplemental Type Approvals (STAs) or equivalent action changes
to make sure you can complete this service bulletin.

### Page 3

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 2 of 15
Sep 13/2022
Revision A, May 24/2023
B. Reason
(1) Condition
Bleed air duct from anti-ice system found with missing part of the
insulation/heat shield in the pylon area. This condition results into a direct
heat radiation from the bare duct skin to the pylon area. Exposure to elevated
temperatures on the structure has an influence on the behavior and stress
level encountered in the area concerned.
(2) Evidence
Missing parts of the insulation/heat shield on the bleed duct from the wing
anti-ice system in the pylon area.
(3) Objective/Benefit
This service bulletin gives the procedure to do a one time inspection to
examine the spars and firewall for signs of corrosion, cracks, abnormal
waviness and other type of damage.
C. Description
The left and right pylon access panels are removed. A visual inspection is done on
spars at FS654.50, FS672.20 and on the firewall. If damage is found, a damage
report form is filled and sent to MHIRJ Technical Help Desk (THD). The pylon
access panels are installed.
D. Compliance
MHIRJ recommends that this service bulletin be done at no more than 6600 flight
hours or no later than 48 months from the release date on this service bulletin,
whichever comes first, unless otherwise directed by the airworthiness authority of
the operator.
NOTE: If it is not possible to complete all the instructions in this service bulletin
because of the configuration of the aircraft, speak with a representative
of MHIRJ in the CRC at 450-990-7CRC (450-990-7272) direct,
1-833-990-7CRC (1-833-990-7272) toll free for North America or
+1-450-990-7CRC (+1-450-990-7272) for international callers or
e‐mail at thd.crj@MHIRJ.com for analysis and to get an approved
disposition to complete this service bulletin.
This service bulletin does not affect Airworthiness Limitations (AWLs) or Damage
Tolerance Inspections (DTIs).
E. Approval
The technical content of this service bulletin has been approved under the authority
of the TCCA Design Approval Organization No: DAO #20-Q-01.

### Page 4

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 3 of 15
Sep 13/2022
Revision A, May 24/2023
F . Manpower
The man‐hours given below are estimates for direct labor done by an experienced
crew on an aircraft prepared for maintenance.
These estimates do not include the time necessary for:
-Administrative functions such as planning, liaising, familiarization, and report writing.
-Non‐productive elapsed time such as rest time, having meals, and crew shift
changes.
-Elapsed time such as for paint to dry, sealant to cure, and fuel tank venting.
-Preparation for modification (unless specified in the Accomplishment
Instructions) such as cleaning and getting parts, tools, consumables, and
ground equipment.
-Quality assurance inspections, troubleshooting and/or correction of
discrepancies found when a task is done.
-All other activities that are not considered by MHIRJ as directly related to the
accomplishment of this procedure.
NOTE: For on‐site labor assistance, please speak with a Fleet Services
representative for an estimate. Call the Fleet Services Team through the
CRC at 450-990-7CRC (450-990-7272) direct, 1-833-990-7CRC
(1-833-990-7272) toll free for North America or +1-450-990-7CRC
(+1-450-990-7272) for international callers or e‐mail at
thd.crj@MHIRJ.com.
It will take an estimated 6.0 man‐hours to complete this service bulletin. The
man‐hours are divided in the table that follows (elapsed cure time is not included in
the man‐hour summary given above):
TASK MAN‐HOURS
(1)  Job Set‐Up 2.0
(2)  Procedure 2.0
(3)  Test N/A
(4)  Job Close‐Out 2.0
NOTE: The man‐hours for the procedure do not include the hours to replace
damaged parts.

### Page 5

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 4 of 15
Sep 13/2022
Revision A, May 24/2023
G. Material - Price and Availability
There are no kits for this service bulletin.
H. Tooling - Price and Availability
There are no tool kits for this service bulletin. Refer to paragraph 3.C. for a list of
special tools and equipment for this service bulletin.
I. Weight and Balance
Not changed.
J. Electrical Load Data
Not changed.
K. References
Refer to the SB Introduction document for definition or explanation of service
bulletin content.
For MHIRJ reference only: Restriction and/or Special Instruction (RSI) C-A314,
Revision A.
For MHIRJ reference only: 7464.
L. Other Publications Affected
None.
M. Relationship Chart
Not applicable.

### Page 6

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 5 of 15
Sep 13/2022
Revision A, May 24/2023
2. ACCOMPLISHMENT INSTRUCTIONS
Reference Information
REFERENCE DESIGNATION
AMM 54-60-01-000-802 Removal of the Forward Mount Lower-
Access-Panels
AMM 54-60-01-000-803 Removal of the Forward Mount Upper-
Access-Panels
AMM 54-60-01-000-804 Removal of the Lines Disconnect Inboard-
Access-Panels
AMM 54-60-01-000-805 Removal of the Lines Disconnect Upper-
Access-Panels
AMM 54-60-01-000-806 Removal of the Rear Mount Inboard-
Access-Panels
AMM 54-60-01-000-808 Removal of the Lines Disconnect Outboard-
Access-Panels
AMM 54-60-01-000-809 Removal of the Rear Mount Center-
Access-Panels
AMM 54-60-01-400-802 Installation of the Forward Mount Lower-
Access-Panels
AMM 54-60-01-400-803 Installation of the Forward Mount Upper-
Access-Panels
AMM 54-60-01-400-804 Installation of the Lines Disconnect Inboard-
Access-Panels
AMM 54-60-01-400-805 Installation of the Lines Disconnect Upper-
Access-Panels
AMM 54-60-01-400-806 Installation of the Rear Mount Inboard-
Access-Panels
AMM 54-60-01-400-808 Installation of the Lines Disconnect Outboard-
Access-Panels

### Page 7

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 6 of 15
Sep 13/2022
Revision A, May 24/2023
REFERENCE DESIGNATION
AMM 54-60-01-400-809 Installation of the Rear Mount Center-Access-
Panels
SRM 51-13-01 Defect and Damage Repair Request-Report
Procedure
SRM 51-26-00 Cleaning
A. Job Set‐Up
NOTE: The steps in the Job Set‐Up section of this service bulletin are
recommended steps. The steps give a recommendation to get access
to the work area. This recommendation is to give a safe work area and
to minimize possible damage to surrounding aircraft parts. Alternative
steps can be used at the operator discretion.
For Aircraft 7031, 7045, 7069, 7188, 7212, 7217, 7243, 7258, 7269, 7271, 7276, 7284,
7290, 7302, 7310, 7328, 7339, 7342, 7355, 7358, 7401, 7437, 7441, 7448, 7458, 7476,
7479, 7495, 7517, 7530, 7532, 7548, 7579, 7582, 7586, 7588, 7599, 7606, 7609, 7623,
7648, 7657, 7667, 7681, 7687, 7715, 7727, 7743, 7748, 7750, 7758, 7780, 7818, 7821,
7822, 7892, 7895, 7909, 7913, 7920, 7922, 7923, 7926, 7932, 7937 and 7964
(1) Remove the left pylon access panels that follow:
PANEL NAME REFERENCE
412AB Forward Mount Lower-
Access-Panel
54-60-01-000-802
412BB Lines Disconnect In­
board-Access Panel
54-60-01-000-804
412CB Rear Mount Inboard-
Access-Panel
54-60-01-000-806
412DB Lines Disconnect Out­
board-Access-Panel
54-60-01-000-808
412EB Rear Mount Center-
Access-Panel
54-60-01-000-809
NOTE: If required, the pylon access panels 412AT and 412BT can be removed
to have a view from the top of the pylon (refer to AMM
54-60-01-000-803 and 54-60-01-000-805).

### Page 8

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 7 of 15
Sep 13/2022
Revision A, May 24/2023
For Aircraft 7045, 7078, 7089, 7102, 7110, 7168, 7203, 7212, 7217, 7229, 7231, 7236,
7257, 7258, 7269, 7271, 7276, 7290, 7302, 7304, 7306, 7310, 7328, 7342, 7355, 7358,
7360, 7401, 7404, 7441, 7474, 7502, 7503, 7527, 7548, 7551, 7574, 7575, 7579, 7582,
7586, 7599, 7600, 7632, 7658, 7664, 7674, 7682, 7683, 7715, 7748, 7749, 7758, 7760,
7769, 7810, 7817, 7818, 7821, 7822, 7857, 7859, 7871, 7873, 7889, 7892, 7912, 7929,
7935, 7954, 7961 and 8011
(2) Remove the right pylon access panels that follow:
PANEL NAME REFERENCE
422AB Forward Mount Low­
er-Access-Panel
54-60-01-000-802
422BB Lines Disconnect In­
board-Access Panel
54-60-01-000-804
422CB Rear Mount Inboard-
Access-Panel
54-60-01-000-806
422DB Lines Disconnect Out­
board-Access-Panel
54-60-01-000-808
422EB Rear Mount Center-
Access-Panel
54-60-01-000-809
NOTE: If required,the pylon access panels 422AT and 422BT can be removed
to have a view from the top of the pylon (refer to AMM
54-60-01-000-803 and 54-60-01-000-805).

### Page 9

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 8 of 15
Sep 13/2022
Revision A, May 24/2023
For all aircraft
B. Procedure
(1) If it is not possible to complete all the instructions in this service bulletin
because of the configuration of the aircraft, speak with a representative of
MHIRJ in the CRC at 450-990-7CRC (450-990-7272) direct,
1-833-990-7CRC (1-833-990-7272) toll free for North America or
+1-450-990-7CRC (+1-450-990-7272) for international callers or e‐mail
at thd.crj@MHIRJ.com for analysis and to get an approved disposition to
complete this service bulletin.
For Aircraft 7031, 7045, 7069, 7188, 7212, 7217, 7243, 7258, 7269, 7271, 7276, 7284,
7290, 7302, 7310, 7328, 7339, 7342, 7355, 7358, 7401, 7437, 7441, 7448, 7458, 7476,
7479, 7495, 7517, 7530, 7532, 7548, 7579, 7582, 7586, 7588, 7599, 7606, 7609, 7623,
7648, 7657, 7667, 7681, 7687, 7715, 7727, 7743, 7748, 7750, 7758, 7780, 7818, 7821,
7822, 7892, 7895, 7909, 7913, 7920, 7922, 7923, 7926, 7932, 7937 and 7964
NOTE: The steps that follow are applicable for the spars and firewall on the left
pylon.
Refer to Figure 1.
(2) Clean the forward and aft surfaces of the left pylon spar FS654.50 (1) 
(refer to SRM 51-26-00).
(3) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).
(4) Clean the forward and aft surfaces of the left pylon spar FS672.20 (2) 
(refer to SRM 51-26-00).
(5) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).

### Page 10

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 9 of 15
Sep 13/2022
Revision A, May 24/2023
(6) Clean the inboard and outboard surfaces of the left pylon firewall assembly
(3) (refer to SRM 51-26-00).
(7) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).
(8) Do a detailed visual inspection on the structure assembly of the forward and
aft sides of the left pylon spar FS654.50 (1) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.
(9) Do a detailed visual inspection on the structure assembly of the forward and
aft sides of the left pylon spar FS672.20 (2) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.
(10) Do a detailed visual inspection on the structure assembly of the left pylon
firewall (3) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.

### Page 11

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 10 of 15
Sep 13/2022
Revision A, May 24/2023
For Aircraft 7045, 7078, 7089, 7102, 7110, 7168, 7203, 7212, 7217, 7229, 7231, 7236,
7257, 7258, 7269, 7271, 7276, 7290, 7302, 7304, 7306, 7310, 7328, 7342, 7355, 7358,
7360, 7401, 7404, 7441, 7474, 7502, 7503, 7527, 7548, 7551, 7574, 7575, 7579, 7582,
7586, 7599, 7600, 7632, 7658, 7664, 7674, 7682, 7683, 7715, 7748, 7749, 7758, 7760,
7769, 7810, 7817, 7818, 7821, 7822, 7857, 7859, 7871, 7873, 7889, 7892, 7912, 7929,
7935, 7954, 7961 and 8011
NOTE: The steps that follow are applicable for the spars and firewall on the right
pylon.
Refer to Figure 1.
(11) Clean the forward and aft surfaces of the right pylon spar FS654.50 (1) 
(refer to SRM 51-26-00).
(12) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).
(13) Clean the forward and aft surfaces of the right pylon spar FS672.20 (2) 
(refer to SRM 51-26-00).
(14) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).
(15) Clean the inboard and outboard surfaces of the right pylon firewall assembly
(3) (refer to SRM 51-26-00).
(16) If the inspection surfaces are painted, do as follows:
(a) Look at the paint condition for signs of cracks and corrosion in the
component material.
(b) Remove the paint and/or primer only if there is deterioration or local
damage (refer to SRM 51-26-00).

### Page 12

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 11 of 15
Sep 13/2022
Revision A, May 24/2023
(17) Do a detailed visual inspection on the structure assembly of the forward and
aft sides of the right pylon spar FS654.50 (1) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.
(18) Do a detailed visual inspection on the structure assembly of the forward and
aft sides of the right pylon spar FS672.20 (2) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.
(19) Do a detailed visual inspection on the structure assembly of the right pylon
firewall (3) as follows:
(a) Visually inspect for all signs of corrosion or cracks.
(b) Visually inspect for all signs of damaged fasteners.
(c) Visually inspect for all signs of web waviness or flatness.
For all aircraft
(20) If damage is found, fill the damage report form for Fuselage Skin damage
(refer to SRM 51-13-01).
NOTE: All the damages found during the visual inspection must be reported in
the damage report.
.
(21) If damage is found, send a copy of the damage report form to the Customer
Response Center (CRC) at the following e-mail address:
thd.crj@MHIRJ.com.
NOTE: MHIRJ will inform if additional action is recommended.
(22) If damage is found outside the scope of this service bulletin, speak with a
CRC representative at 450-990-7CRC (450-990-7272) direct,
1-833-990-7CRC (1-833-990-7272) toll free for North America or
+1-450-990-7CRC (+1-450-990-7272) for international callers or send
an e‐mail at thd.crj@MHIRJ.com for a disposition.

### Page 13

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 12 of 15
Sep 13/2022
Revision A, May 24/2023
C. Job Close‐Out
NOTE: The steps in the Job Close‐Out section of this service bulletin, except for
the return‐to‐service tests, are recommended steps. The steps give a
recommendation to install components removed during the Job Set‐Up.
This recommendation is to make sure that the aircraft is safe and ready
to return to service. Alternative steps can be used at the operator
discretion.
(1) Remove all tools, equipment, and unwanted materials from the work area.
For Aircraft 7031, 7045, 7069, 7188, 7212, 7217, 7243, 7258, 7269, 7271, 7276, 7284,
7290, 7302, 7310, 7328, 7339, 7342, 7355, 7358, 7401, 7437, 7441, 7448, 7458, 7476,
7479, 7495, 7517, 7530, 7532, 7548, 7579, 7582, 7586, 7588, 7599, 7606, 7609, 7623,
7648, 7657, 7667, 7681, 7687, 7715, 7727, 7743, 7748, 7750, 7758, 7780, 7818, 7821,
7822, 7892, 7895, 7909, 7913, 7920, 7922, 7923, 7926, 7932, 7937 and 7964
(2) Install the access panels that follow:
PANEL NAME REFERENCE
412AB Forward Mount Lower-
Access-Panel
54-60-01-400-802
412BB Lines Disconnect In­
board-Access Panel
54-60-01-400-804
412CB Rear Mount Inboard-
Access-Panel
54-60-01-400-806
412DB Lines Disconnect Out­
board-Access-Panel
54-60-01-400-808
412EB Rear Mount Center-
Access-Panel
54-60-01-400-809
NOTE: If the pylon access panels 412AT and 412BT have been removed, they
need to be installed (refer to AMM 54-60-01-400-803 and
54-60-01-400-805).

### Page 14

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 13 of 15
Sep 13/2022
Revision A, May 24/2023
For Aircraft 7045, 7078, 7089, 7102, 7110, 7168, 7203, 7212, 7217, 7229, 7231, 7236,
7257, 7258, 7269, 7271, 7276, 7290, 7302, 7304, 7306, 7310, 7328, 7342, 7355, 7358,
7360, 7401, 7404, 7441, 7474, 7502, 7503, 7527, 7548, 7551, 7574, 7575, 7579, 7582,
7586, 7599, 7600, 7632, 7658, 7664, 7674, 7682, 7683, 7715, 7748, 7749, 7758, 7760,
7769, 7810, 7817, 7818, 7821, 7822, 7857, 7859, 7871, 7873, 7889, 7892, 7912, 7929,
7935, 7954, 7961 and 8011
(3) Install the access panels that follow:
PANEL NAME REFERENCE
422AB Forward Mount Low­
er-Access-Panel
54-60-01-400-802
422BB Lines Disconnect In­
board-Access Panel
54-60-01-400-804
422CB Rear Mount Inboard-
Access-Panel
54-60-01-400-806
422DB Lines Disconnect Out­
board-Access-Panel
54-60-01-400-808
422EB Rear Mount Center-
Access-Panel
54-60-01-400-809
NOTE: If the pylon access panels 422AT and 422BT have been removed, they
need to be installed (refer to AMM 54-60-01-400-803 and
54-60-01-400-805).
For All Aircraft
(4) When this service bulletin is completed, make this entry in the applicable
logbooks: “Service Bulletin 601R-54-006, Revision A,
Nacelle/Pylons-Spars and Firewall-Inspection of Pylons Structure at the
Fuselage Station 654.50 and 672.20, incorporated.”

### Page 15

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 14 of 15
Sep 13/2022
Revision A, May 24/2023
Pylon-Inspection Area-Spars and Firewall
Figure 1 
rsb601r54006_001.cgm, gd, jun27/2022
LEGEND
1. Spar FS654.50.
2. Spar FS672.20.
3. Firewall.
A
FS605.00
FS619.18
FS640.00FS625.30
FS654.50
FS682.00
FS672.20
1
2
3
A
NOTE
      Left side shown,
      right side opposite.

### Page 16

SERVICE BULLETIN  601R-54-006
SB 601R-54-006
Page 15 of 15
Sep 13/2022
Revision A, May 24/2023
3. MATERIAL INFORMATION
A. Kit Information
None.
B. Consumable Information
For a list of consumables, refer to the different tasks that are given as references in
this service bulletin.
C. Special Tools and Equipment
For a list of special tools and equipment, refer to the different tasks that are given
as references in this service bulletin.
D. Disposition of Parts
Not applicable.
1

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