# 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 airc raft 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, NoneSERVICE 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 extinguishin g 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 mandator y 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 ATR72Original issue - Jul 18/12 Service Bulletin No. ATR72-54-1023Page IL-1©ATR. All rights reserved. Confidential and proprietary document.ILLUSTRATIONSIn zones 470 and 480, junction between bottom structureand underwing box forward frameFigure 1, sheet 1 of 2SERVICE 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