SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page TS-1 of TS-2 

TRANSMITTAL SHEET

Original issue 

This page transmits Original issue of Service Bulletin No. ATR72-54-1023. 

General information concerning this document is available in Service Letter No. ATR72-00-6005. 

TITLE: Nacelles/Pylons - Junction between bottom structure and underwing box - 

Sealing inspection 

© ATR. All rights reserved. Confidential and proprietary document. 

This document shall not be reproduced or disclosed to a third party 

without the written consent of ATR. This document and its content 

shall not be used for any purpose other than that for which it is supplied. 

ATR, its logo, the distinctive ATR aircraft profiles and patented information 

relating to the ATR aircraft are the exclusive property of ATR and are subject 

to copyright. This document and all information contained herein are the sole 

property of ATR. No intellectual property right is granted through, or induced by, 

the delivery of this document or the disclosure of its content. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

Page TS-2 of TS-2 © ATR. All rights reserved. Confidential and proprietary document. 

1 – TABLE OF CONTENTS 

TRANSMITTAL SHEET ...................................................................................Page TS-1 to TS-2 

ACCOMPLISHMENT REPORT ...................................................................... Page AR-1 to AR-3 

PLANNING INFORMATION............................................................................... Page PI-1 to PI-4 

MATERIAL INFORMATION.............................................................................. Page MI-1 to MI-2 

ACCOMPLISHMENT INSTRUCTIONS ............................................................. Page AI-1 to AI-4 

ILLUSTRATIONS................................................................................................ Page IL-1 to IL-2 

2 – REVISION SEQUENCES 

Issue or Revision Date Additional work 

 

Original issue Jul 18/12 - 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AR-1 © ATR. All rights reserved. Confidential and proprietary document. 

ACCOMPLISHMENT REPORT 

SERVICE BULLETIN No. ATR72-54-1023 

Original issue 

Send this report to: 

ATR ENGINEERING 

SERVICE BULLETIN GROUP 

1 ALLEE PIERRE NADOT 

31712 BLAGNAC CEDEX 

FRANCE 

phone : +33 (0)5 62 21 62 21 

fax : +33 (0)5 62 21 69 41 

e-mail : techdesk@atr.fr 

Aircraft identification

Service Bulletin accomplished on aircraft MSN: 

Service Bulletin accomplishment date: 

Aircraft registration number: 

Number of flights: 

Flight hours: 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AR-2 © ATR. All rights reserved. Confidential and proprietary document. 

Inspection results

Tick (3) the appropriate box 

 LH nacelle RH nacelle 

Minimum gap measured 

between rear bottom cowl 

and underwing box 

............. mm 

or 

............. in 

............ mm 

or 

............. in 

Minimum flushness 

measured between rear 

bottom cowl and 

underwing box 

............. mm 

or 

............. in 

............ mm 

or 

............. in 

Maximum gap measured 

between rear bottom cowl 

and underwing box 

............. mm 

or 

............. in 

............ mm 

or 

............. in 

Maximum flushness 

measured between rear 

bottom cowl and 

underwing box 

............. mm 

or 

............. in 

............ mm 

or 

............. in 

In which condition is the 

seal Item 2? 

Missing Damaged Correct Missing Damaged Correct 

In which condition is the 

LH shim Item 1A? 

Missing Damaged Correct Missing Damaged Correct 

In which condition is the 

RH shim Item 1B? 

Missing Damaged Correct Missing Damaged Correct 

Remarks: ___________________________________________________________________ 

 ___________________________________________________________________ 

 ___________________________________________________________________ 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AR-3 © ATR. All rights reserved. Confidential and proprietary document. 

Performed action(s): __________________________________________________________ 

 __________________________________________________________ 

 __________________________________________________________ 

Maintenance organisation identification

Maintenance organisation name: 

Name & Signature: 

Date: 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

Page PI-1 © ATR. All rights reserved. Confidential and proprietary document. 

COMPLIANCE: MANDATORY INSPECTION: 002/2012 

TITLE: Nacelles/Pylons - Junction between bottom structure and underwing box - 

Sealing inspection 

1. PLANNING INFORMATION

A. EFFECTIVITY

(1) Aircraft models 

ATR72-101 ATR72-102 ATR72-201 ATR72-202 ATR72-211 ATR72-212 ATR72-212A

YES YES YES YES YES YES YES 

(2) Aircraft 

MSN Kit(s) 

108, 126, 140, 145, 147, 150, 154, 157, 162, 

164, 167, 171, 174, 177, 180, 183, 186, 189, 

192, 195, 198, 201, 204, 207, 210, 212, 215, 

217, 220, 222, 224, 227, 229, 232, 234, 237, 

239, 241, 244, 246, 248, 251, 253, 256, 260, 

263, 265, 267, 270, 272, 274, 276, 279, 281, 

283, 285, 288, 290, 292, 294, 297, 299, 301, 

303, 305, 307, 309, 311, 313, 316, 320, 324, 

326, 328, 330, 334, 336, 338, 339, 341, 342, 

344, 345, 347, 349, 350, 352, 353, 355, 357, 

359, 361, 362, 364, 365, 367, 369, 370, 372, 

373, 375, 377, 379, 381, 383, 385, 387, 389, 

391, 393, 395, 396, 398, 399, 402, 404, 405, 

407, 408, 410, 411, 414, 416, 417, 419, 420, 

422, 423, 425, 426, 428, 429, 431, 432, 434, 

437, 440, 441, 444, 446, 447, 448, 449, 450, 

451, 452, 453, 455, 456, 460, 461, 463, 464, 

None 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

Page PI-2 © ATR. All rights reserved. Confidential and proprietary document. 

MSN (continued) Kit(s) 

465, 467, 468, 469, 470, 472, 473, 475, 477, 

479, 481, 482, 483, 485, 486, 488, 489, 493, 

494, 496, 498, 499, 508, 509, 517, 519, 521, 

523, 525, 527, 529, 531, 533, 535, 536, 538, 

540, 541, 543, 545, 547, 548, 550, 552, 553, 

555, 557, 558, 560, 562, 563, 565, 567, 568, 

570, 572, 573, 575, 577, 578, 580, 582, 583, 

585, 587, 588, 590, 592, 593, 595, 597, 598, 

600, 624, 626, 628, 630, 632, 634, 636, 638, 

642, 644, 646, 648, 650, 652, 654, 656, 658, 

660, 662, 664, 666, 668, 672, 674, 676, 677, 

678, 679, 680, 681, 682, 683, 684, 685, 686, 

687, 688, 690, 692, 694, 696, 697, 698, 699, 

700, 701, 702, 703, 704, 705, 706, 707, 708, 

709, 710 

None 

(3) Spares 

The following stock items are modifiable (or not) according to the table below. 

None. 

B. REASON

Some cases of defective sealing have been evidenced on in-service aircraft on LH and RH 

nacelles at level of the junction between the bottom structure and the underwing box. 

Defective sealing may decrease the extinguishing agent efficiency, delay the fire extinction 

and allow fire propagation out of the engine fire area. 

Accomplishment of this Service Bulletin consists in inspecting on the nacelles the sealing 

between bottom structure and the underwing box, and to recover the correct design if 

necessary. 

COMPLIANCE: Accomplishment of this Service Bulletin is mandatory. 

 An Airworthiness Directive will be issued by EASA. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

Page PI-3 © ATR. All rights reserved. Confidential and proprietary document. 

C. DESCRIPTION

Accomplishment of this Service Bulletin consists in carrying out the following jobs: 

(1) On LH and RH nacelles, inspection of the junction between bottom structure and 

underwing box forward frame 

According to inspection results: 

(2) On engine nacelle, at level of the bottom structure to underwing box junction, 

replacement of the shims 

(3) On engine nacelle, at level of the bottom structure to underwing box junction, 

replacement of the seal 

D. APPROVAL

The technical content of this document is approved in accordance with 

CE 1702/2003 regulation and is rendered mandatory by an EASA Airworthiness Directive. 

E. MANPOWER

Manhours 

Mechanic 40 

Electrician None 

Total manhours 40 

Elapsed time (hours) 20 

The above estimates are only provided for general guidance in operator's modification 

planning. 

NOTE: This Service Bulletin assumes that the aircraft has been placed in the appropriate 

maintenance configuration. The manhours/elapsed time estimates do not include 

preparation for the inspection, non-productive elapsed time or administrative 

functions. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

Page PI-4 © ATR. All rights reserved. Confidential and proprietary document. 

F. WEIGHT AND BALANCE

None. 

G. REFERENCES

The following publications have to be used during accomplishment of this Service Bulletin: 

AMM (JIC) : 24-40-00 EAD 10000

54-12-61 RAI 10000

54-22-61 RAI 10000

H. AFFECTED PUBLICATIONS

(1) Maintenance documentation 

None. 

(2) Operational documentation 

None. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page MI-1 © ATR. All rights reserved. Confidential and proprietary document. 

2. MATERIAL INFORMATION

A. MATERIAL - COST AND AVAILABILITY

(1) Material 

Parts cost and availability, or any further commercial information about Service 

Bulletin, may be consulted through ATRactive or operator should contact ATR at the 

following addresses: 

www.atractive.com 

ATR CUSTOMER SERVICES 

SPARES SUPPORT 

1 ALLEE PIERRE NADOT 

31712 BLAGNAC CEDEX 

FRANCE 

phone : +33 (0)5 62 21 60 33 

fax : +33 (0)5 62 21 62 80 

e-mail : spares.quotations@atr.fr 

Or operator should contact the ATR center it is related to, according to its operational 

area, at the following addresses: 

ATR NORTH AMERICA 

45195 BUSINESS COURT, SUITE 450 

DULLES, VIRGINIA 20166 

USA 

phone : +1 571 203 6920 

fax : +1 571 203 6903 

e-mail : commercialservices@atrnorthamerica.com 

ATR EASTERN SUPPORT Pte Ltd. 

51 CHANGI BUSINESS PARK CENTRAL 2 

#08-02 THE SIGNATURE 

SINGAPORE 486066 

phone : +65 6542 0122 

fax : +65 6542 1047 

e-mail : commercial.services@atr.com.sg 

Operator should place a purchase order specifying parts reference through ATRactive 

or to the ATR center it is related to according to its operational area. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page MI-2 © ATR. All rights reserved. Confidential and proprietary document. 

B. LIST OF COMPONENTS

Item Part Number Qty Description 

 

 Material 

 

3 ASNA2051DCJ2412 8* Rivet 

1A 

or 

1B 

S5431026820000 4* Shim 

2 S5411029221500 2* Seal 

 

* Quantity depending on inspection result (maximum quantity indicated) 

C. LIST OF MATERIALS - OPERATOR SUPPLIED

None. 

D. SPECIAL TOOLS

Accomplishment of this Service Bulletin requires use of the following special tools: 

None. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AI-1 © ATR. All rights reserved. Confidential and proprietary document. 

3. ACCOMPLISHMENT INSTRUCTIONS

A. GENERAL

The following instructions assume that work will be accomplished when the aircraft is in 

the appropriate maintenance configuration. 

B. JOB SET-UP

(1) De-energize the aircraft electrical network and connect the aircraft to ground as per 

AMM (JIC) 24-40-00 EAD 10000. 

(2) Install warning notice in flight compartment indicating that work on engines is in 

progress. 

(3) Install access platform to get access to zones 451 and 461. 

(4) Install container under LH and RH drain masts and under LH and RH engine oil cooler 

flaps. 

(5) Install fire fighting equipment. 

C. INSPECTION

CAUTION: THE INSPECTION DESCRIBED BELOW IS PRESENTED FOR ONE ENGINE 

NACELLE. ALL OPERATIONS MUST BE PERFORMED ON THE LH ENGINE 

NACELLE AND THE RH ENGINE NACELLE. 

NOTE: After accomplishment of this Service Bulletin, fill the enclosed Accomplishment 

Report and send it to the address mentioned on the Accomplishment Report. 

(1) Inspection of the junction between bottom structure and underwing box forward frame 

As per Figure 1 

(a) Measure and record minimum and maximum gaps and flushness between the 

rear bottom cowl and the underwing box. 

(b) Between bottom structure and underwing box forward frame, check presence 

and position of seals and check for presence of dirt. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AI-2 © ATR. All rights reserved. Confidential and proprietary document. 

(c) Remove the rear bottom structure as per AMM (JIC) 54-22-61 RAI 10000 or 

remove the bottom structure as per AMM (JIC) 54-12-61 RAI 10000. 

(d) Check presence and position of the seal Item 2 and of the two lateral Teflon 

shims Item 1A and 1B. 

Check for presence of dirt and clean the area if necessary. 

- If at least one item is damaged or missing, perform paragraph 3.D.(1) and/or 

3.D.(2). 

- If no item is damaged or missing, perform paragraph 3.F. 

D. MODIFICATION

CAUTION: THE MODIFICATIONS DESCRIBED BELOW ARE PRESENTED FOR ONE 

ENGINE NACELLE. ALL OPERATIONS MUST BE PERFORMED ON THE LH 

ENGINE NACELLE AND THE RH ENGINE NACELLE. 

(1) On engine nacelle, at level of the bottom structure to underwing box junction, 

replacement of the shims 

(a) Remove all the parts listed in the following table. Carefully follow the specific 

instruction(s) detailed after the table. 

REMOVAL 

Item Description Part Number Qty 

Discarded 

Qty 

Re-used Figure

 

1A 

or 

1B 

Shim S5431026820000 2* - 1 

3 Rivet - 4* - 1 

 

* Quantity depending on inspection result (maximum quantity indicated). 

Specific instruction(s): 

Remove two rivets Item 3 per shim Item 1A or 1B. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AI-3 © ATR. All rights reserved. Confidential and proprietary document. 

(b) Install all the parts listed in the following table. Carefully follow the specific 

instruction(s) detailed after the table. 

INSTALLATION 

Item Description Part Number Qty 

New 

Qty from

Removal Figure

 

1A 

or 

1B 

Shim S5431026820000 2* - 1 

3 Rivet ASNA2051DCJ2412 4* - 1 

 

* Quantity depending on inspection result (maximum quantity indicated). 

Specific instruction(s): 

Install two rivets Item 3 per shim Item 1A or 1B. 

(2) On engine nacelle, at level of the bottom structure to underwing box junction, 

replacement of the seal 

(a) Remove all the parts listed in the following table. 

REMOVAL 

Item Description Part Number Qty 

Discarded 

Qty 

Re-used Figure

 

2 Seal S5411029221500 1* - 1 

* Quantity depending on inspection result (maximum quantity indicated). 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page AI-4 © ATR. All rights reserved. Confidential and proprietary document. 

(b) Install all the parts listed in the following table. 

INSTALLATION 

Item Description Part Number Qty 

New 

Qty from

Removal Figure

 

2 Seal S5411029221500 1* - 1 

* Quantity depending on inspection result (maximum quantity indicated). 

E. TESTS

None. 

F. CLOSE-UP

(1) Re-install the rear bottom structure as per AMM (JIC) 54-22-61 RAI 10000 or re-install 

the bottom structure as per AMM (JIC) 54-12-61 RAI 10000. 

(2) Remove fire fighting equipment. 

(3) Remove container under drain masts and under LH and RH oil cooler flaps. 

(4) Remove access platform. 

(5) Remove warning notice in flight compartment indicating that work on engines is in 

progress. 

(6) Re-energize the aircraft electrical network and disconnect the aircraft from ground as 

per AMM (JIC) 24-40-00 EAD 10000. 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page IL-1 

© ATR. All rights reserved. Confidential and proprietary document. 

ILLUSTRATIONS 

In zones 470 and 480, junction between bottom structure 

and underwing box forward frame 

Figure 1, sheet 1 of 2 
SERVICE BULLETIN ATR72 

Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023 

 Page IL-2 © ATR. All rights reserved. Confidential and proprietary document. 

In zones 470 and 480, junction between bottom structure 

and underwing box forward frame 

Figure 1, sheet 2