# McDonnell Douglas Service Bulletin A53-232: Revision 2 - Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2014-0232; AD 2014-22-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [McDonnell Douglas Service Bulletin A53-232](https://openairdocs.org/service-documents/boeing/a53-232.md) - Title as filed: U.S. DOT/FAA - SB-DC9-A53-232-r2 - Pages: 59 - PDF: https://openairdocs.org/files/sha256/b5/c0/b5c0d481acaee5969f5a1a65f55abfbaa74df8a541640e47bd42bd896561de11 - Page: https://openairdocs.org/service-documents/boeing/a53-232/file/b5c0d481acae ## Text This text is OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 (OCR) DOUGLAS AIRCRAFT COMPANY ALERT MCDONNELL DOUGLAS DC-S BULLETIN A53-232 SERVICE BULLETIN REVISION TRANSMITTAL SHEET FUSELAGE - Main Frame - Inspect/Repair Aft Fuselage Ventral Pressure Bulkhead Tee. This page transmits Revision 2 for DC-9 Alert Service Bulletin A53-232 to incorporate the following changes: NOTE: Turf nt operat This revision constitutes a complete reissue and reflects current operators of affected aircraft at time of issue. Reason for Revision: To add two aircraft to this Alert Service Bulletin Effectivity which are affected by this modification. No additional work is required by this revision for aircraft previously inspected/repaired by prior issue of this Alert Service Bulletin. Pages 2 Added two aircraft to Service Bulletin effectivity as follows: and 8: OPR FUS (ESN) OPR EUS (ESN) AM 718 (47602) ZXE 173 (47016) Page 15: Revised Approval. Page 55: Revised supplier address in paragraph 3.C.(1). Revision Sequence: Original Date March 28/90 Revision 1 June 25/93 Revision 2. April 28/95 ENW AMM-3 DOUGLAS AIRCRAFT COMPANY MCDONNELL DOUGLAS CORPORATION PRODUCT SUPPORT McDonnell Douglas Corporation (MDC) proprietary rights are included in the information disclosed herein, and recipient by accepting this document agreesthat the information is proprietary to MDC. MDC authorizes recipient to reproduce such information in other documents created for internal use if these documents are protected similarly by a proprietary legend. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 1 of 1 ### Page 2 (OCR) DOUGLAS AIRCRAFT COMPANY ALERT MCDONNELL DOUGLAS DC-S P.O. Box 1771 BULLETIN A53-232 Long Beach, CA 90801 SERVICE BULLETIN FUSELAGE - Main Frame - Inspect/Repair Aft Fuselage Ventral Pressure Bulkhead Tee. NOTE This Alert Service Bulletin is affected by Federal Aviation Administration Airworthiness Directive No. 89-16-12: Amendment 39-6287, effective September 7, 1989. This Alert Service Bulletin is applicable only to aircraft equipped with ventral aft pressure bulkhead which have accumulated 35,000 or more landings. Replacement of all six aft pressure bulkhead tee sections with new improved parts per this Alert Service Bulletin constitutes closing action for the repetitive inspection requirements of this Alert Service Bulletin. This Alert Service Bulletin supersedes but does not cancel the requirements of DC-9 Alert Service Bulletin A53-191. Only aircraft listed in this Alert Service Bulletin that are contained in the Effectivity of Alert Service Bulletin A53-191 are affected by this contingency. This Alert Service Bulletin is issued as a partial record-type change. A service rework drawing or aperture cards are furnished in lieu of illustrations. McDonnell Douglas Corporation (MDC) proprietary rights are included in the information disclosed herein, and recipient by accepting this document agrees that the information is proprietary to MDC. MDC authorizes recipient to reproduce such information in other documents created for internal use if these documents are protected similarly by a proprietary legend. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 1 of 58 ### Page 3 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN 1. Planning Information: A. Effectivity: (1) Aircraft Affected: DC-9, Series 10, 20, 30, 40, 50, and C-9, DC-9-81 -82, and -83 (MD-81, -82, and -83) (a) Operator and Aircraft Number: Operator Factory Serial No. Operator Factory Serial No. 49145 AO 47640 49155 (cont) 47642 thru 47644 49158 and 49159 47675 49161 thru 49163 47678 49167 and 49168 47704 49171 thru 49181 47707 49251 48104 thru 48106 49253 thru 49259 49269 thru 49273 AS 48079 and 48080 49286 thru 49329 49103 and 49104 49331 and 49332 49111 49126 AM 47006 49231 thru 49236 47106 49363 thru 49365 47394 49386 and 49387 47501 47549 AU 47262 47594 47365 47602 47446 and 47447 47607 47454 47609 48024 and 48025 47650 48067 thru 48069 AY 47604 thru 47606 48083 47613 and 47614 48125 thru 48130 47694 thru 47696 48150 and 48151 47736 thru 47738 49149 47771 thru 47773 49188 thru 49190 48134 thru 48136 49150 thru 49152 AO 47076 49252 47080 49284 47090 thru 47092 47452 AZ 47038 and 47039 47455 47046 and 47047 47461 47101 47504 47128 and 47129 47542 47222 thru 47226 47556 47228 thru 47238 47637 47283 Bulletin A53-232 March 28/90 Page 2 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or discloure of ### Page 4 (OCR) ALERT DoUGLAS aIRcraFT cOMpaNY ALERT SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. AZ 47311 CO 47539 (cont) 47339 (cont) 47638 47432 thru 47438 47765 47502 47788 47518 and 47519 47797 thru 47799 47533 48022 47544 48027 47553 48044 and 48045 47575 48056 47591 48062 and 48063 47641 48066 47653 48073 and 48074 49192 thru 49218 48111 thru 48113 49102 BD 47484 49112 thru 49114 47523 49116 thru 49118 47555 49120 thru 47559 49125 47648 49127 47666 49222 49229 BVZ 47430 49246 47516 47468 49249 49260 and thru 49250 49265 49370 and 49371 49390 49391 thru 49394 CBF 49415 49478 thru 49482 49425 EA 47120 49428 49502 EZ 47044 47061 CEA 49140 and 49141 47191 49355 47194 49501 47279 CO 45789 FP 45731 45791 thru 45793 45847 GA 47385 and 47386 47094 47481 47110 thru 47112 47569 47218 and 47219 47601 47281 47635 47487 47701 47490 47722 ... 47520 and 47521 47730 47524 47740 47531 47744 47535 47789 thru 47795 March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 3 McDonnal Douglas Comoration Proristary Infamation I los a dicterina of ### Page 5 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. GB 45717 IB 47037 47003 and 47004 47079 47008 and 47009 47088 and 47089 47065 47093 47072 47312 and 47313 47084 47368 47176 47453 47201 47456 47203 47702 47257 and 47258 47706 47273 48103 47291 47314 IG 47655 thru 47657 47317 47713 thru 47715 47325 49247 and 49248 47363 and 47364 47380 and 47381 JD 47760 thru 47762 47419 47767 and 47768 47426 and 47427 47780 and 47781 47462 48029 thru 48033 47464 and 47465 48070 thru 48072 47492 thru 47494 49280 thru 49283 47497 thru 47499 47509 thru 47512 JP 47239 47522 47530 47528 47570 47543 48046 47550 thru 47552 48048 47608 48087 47612 49379 47615 and 47616 49440 47619 and 47620 47759 JU 47460 47470 GEC 47783 47532 47562 and 47563 GH 47755 47567 and 47568 47571 HA 47204 47582 47654 47658 KE 49373 and 49374 47661 and 47662 49416 and 49417 47689 47726 LM 49123 and 49124 47735 47742 LV 47000 47763 and 47764 47703 47784 47705 47796 47712 48122 47719 thru 47721 Bulletin A53-232 March 28/90 Page 4 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of ### Page 6 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. LV 47727 NW 47415 thru 47417 (cont) 47752 (cont) 47425 47770 47439 and 47440 47782 47450 49395 47458 and 47459 47469 NK 45788 47472 and 47473 47113 47479 and 47480 47131 47517 47478 47566 47526 47572 and 47573 47547 47647 47651 and 47652 NH 45787 47659 and 47660 45790 47664 45827 47682 47031 47708 thru 47710 47042 47716 thru 47718 47063 and 47064 47724 47073 47729 47078 47739 47083 47756 thru 47758 47103 47769 47114 thru 47117 47774 thru 47776 47138 47785 thru 47787 47149 and 47150 48054 and 48055 47160 48057 47171 48086 47175 48088 thru 48091 47178 thru 47180 48100 thru 48102 47205 and 47206 48107 thru 48110 47244 48121 47246 and 47247 48148 and 48149 47252 thru 47256 49110 47263 and 47264 47280 OS 48015 thru 48021 47282 48059 47286 thru 47288 49115 47315 and 47316 49164 47337 and 47338 49278 and 49279 47346 and 47347 49372 47362 47369 and 47370 QA 47018 47382 and 47383 47389 thru 47391 OD 47278 47395 and 47396 47319 47404 thru 47406 March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 5 McDonal Douatas Comoration Proprintar Information. I lea or disclosina of ### Page 7 (OCR) SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. SK 47301 thru 47303 TH 47711 47305 thru 47308 (cont) 47728 47360 and 47361 47731 thru 47734 47513 47746 47596 and 47597 47749 47599 47751 47610 47753 47623 and 47624 48123 and 48124 47626 thru 47634 49153 and 49154 47646 49156 and 49157 47725 49160 47747 and 47748 49165 and 49166 47750 49169 and 49170 47766 49182 thru 49187 47777 thru 47779 49230 49381 thru 49385 49245 49420 49266 and 49267 49422 and 49423 49366 thru 49369 49436 US 47026 SR 48002 thru 48014 47050 thru 47052 49100 47099 49356 thru 49358 47130 47146 TK 47397 47207 thru 47210 47442 47212 47310 TH 45772 and 45773 47332 45798 and.. 45799 47334 thru 47336 47001 47371 thru 47375 47027 thru 47030 47420 and 47421 47033 47429 47035 47505 47107 thru 47109 47507 and 47508 47172 thru 47174 47564 47248 thru 47251 47574 47324 47576 47343 thru 47345 47583 47357 47588 47411 and 47412 47590 47491 47593 47589 48026 47603 48028 47617 and 47618 48034 thru 48043 47669 48049 47676 48052 and 48053 47686 48092 thru 48099 47688 48114 thru 48120 47693 48131 Bulletin A53-232 March 28/90 Page 6 Revision 2 April 28/95 McDonna Douates Comoration Provista Infration I lee o dieter ~t ### Page 8 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. US 48138 thru 48147 ZAF 47241 and 47242 (cont) 48154 thru 48159 47295 49119 47297 thru 47300 49138 and 49139 47366 and 47367 49142 and 49143 47448 and 47449 49237 47467 49429 47471 49443 47475 47495 VC 47098 47536 thru 47538 47679 47540 and 47541 47743 47668 47745 47670 and 47671 VE 45710 ZBM 47087 47104 and 47105 47121 ZB2 47276 47665 47683 ZCA 45785 and 45786 47685 47692 ZCH 47169 XLL 49402 ZEZ 47525 xQQ 49380 ZE9 47527 49421 47548 49424 ZIG 47595 XYX 45841 47600 47102 47132 and 47133 ZKG 47690 and 47691 47190 47672 and 47673 ZNA 47418 47680 48137 and 48133 ZNV 47410 47428 XZD 45826 47431 47011 47474 47152 47476 and 47477 47496 X5A 45828 47545 47014 47565 47055 47577 and 47578 47086 47580 and 47581 47153 47584 thru 47587 47240 47681 47684 YBB 49101 47687 49277 47698 thru 47700 48137 48165 and 48166 March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 7 McDonnell Doualas Comporation Pronrintary Information. Lisa or dier nema of ### Page 9 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No. ZOQ 47274 ZVQ 47486 47284 (cont) 47488 and 47489 47534 z09 47663 47674 47677 47723 48051 48058 ZVX 49144 47193 ZW7 47466 ZQ9 47005 ZXE 47016 and 47017 47156 47045 47168 47154 and 47155 47170 47202 ZXH 47067 47326 47514 ZXU 47259 ZRS 45797 Z4U 47529 ZUS 45732 Z5B 47007 47358 ZVQ 45774 47177 Z6K 49396 47261 47275 Z6R 47697 47277 47754 47285 47320 47318 thrù 47323. Z8F 47010 47015 47359 47377 thru 47379 1K 47012 and 47013 47443 thru 47445 47062 47451 (b) Other Aircraft: Factory Serial No. 47260 48000 NOTE: Aircraft listed under Other Aircraft are affected by this Service Bulletin but were not assigned to any specific operator at time of Service Bulletin issue. Bulletin A53-232 March 28/90 Page 8 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of ### Page 10 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN (c) Manufacturer's Fuselage and Factory Serial Numbers: EUS (ESN) FUS (FSN) FUS (FSN) EUS (ESN) HUS (FSN) EUS (ESN) 20 (45717) 157 (47029) 225(47129) 312 (47218) 396 (47231) 465(47238) 30 (45772) 161 (47073) 226 (47146) 314 (47176) 397 (47283) 466 (47239) 34(45731) 163 (47079) 228 (47156) 316 (47224) 398 (47311) 468 (47323) 39 (45773) 164 (47080) 229(47132) 317 (47225) 399 (47298) 469 (47324) 41 (45732) 165(47044) 230(47133) 318 (47138) 400(47202) 472 (47344) 46(45841) 167 (47110) 234 (47087) 319 (47117) 401 (47203) 473 (47171) 51 (45797) 168 (47046) 235 (47106) 320 (47263) 409 (47259) 474 (47308) 59 (45798) 170(47152) 236 (47107) 323 (47178) 410(47260) 475(47360) 64(45785) 171 (45788) 237 (47093) 324(47194) 411 (47261) 476 (47357) 69 (45799) 173 (47016) 240 (47190) 325 (47219) 412 (47262) 477 (47358) 79(45826) 174 (47030) 241 (47160) 326 (47256) 413 (47284) 478 (47347) 81 (47004) 177 (47083) 242 (45828) 327 (47209) 414 (47285) 479 (47382) 83 (47000) 178(47035) 244 (47251) 328 (47206) 415 (47337) 480 (47410) 86 (47003) 179 (47084) 245 (47204) 329 (47264) 416 (47338) 484 (47364) 87 (47007) 180 (47088) 250 (47205) 330 (47177) 421 (47299) 485 (47345) 90(45786) 182 (47111) 251 (47108) 333 (47226) 422 (47302) 486 (47042) 94(47001) 183 (47047) 252 (47109) 335 (47179) 423 (47168) 487 (47405) 97 (47010) 184 (47045) 257 (47248) 336 (45774) 424 (47169) 488 (47361) 98 (47008) 185(47153) 261(47115) 337 (47279) 425 (47170) 489 (47389) 99(47006) 186 (47017) 262 (47312) 340 (47295) 426 (47318) 490 (47390) 100(45710) 187 (47031) 263 (47172) 341 (47210) 427 (47281) 491 (47391) 102 (47011) 189 (47089) 264 (45790) 342 (47247) 428 (47232) 492 (47362) 108(47098) 190 (47090) 268 (47313) 343 (47291) 429 (47233) 493 (47334) T11 (47063) 194(47055) 269 (47065) 346 (47240) 432 (47303) 494 (47335) 115(47012) 195(47101) 270 (47072) 347 (47273) 433 (47315) 495 (47359) 118(47050) 197 (47099) 273 (47173) 348 (47274) 434 (47319) 496 (47377) 119 (47026) 198 (47102) 277 (47121) 349 (45791) 435 (47234) 498 (47244) 120 (47064) 199 (47112) 279 (47314) 354 (47180) 436 (47235) 499 (47406) 121 (47037) 201 (47154) 280 (47191) 355 (47228) 437 (47339) 500 (47336) 127 (45787) 202 (47149) 281 (47241) 356 (47229) 438(47300) 501 (47439) 129 (47013) 203 (47018) 284 (47150) 359 (47286) 439 (47316) 502 (47440) 131 (47051) 205 (47103) 286 (47174) 363 (47275) 441 (47305) 504 (47365) 132 (47027) 206 (47091) 292 (47246) 364 (47287) 445 (47363) 505 (47368) 134(47076) 207 (47061) 293 (47207) 368 (47212) 446 (47282) 506 (47371) 135(45827) 209 (47120) 294 (47252) 369 (47288) 449(47310) 508 (47378) 136(47038) 210 (47128) 295 (47253) 372 (45792) 450 (47236) 509 (47379) 141 (47014) 211 (47130) 297 (47249) 373 (47276) 451 (47237) 511 (47415) 142 (47052) 213 (47113) 298 (47175) 377 (47297) 454 (47320) 512 (47416) 143 (47067) 214 (47131) 299 (47222) 379 (47277) 455 (47321) 513 (47372) 145(47028) 216 (47155) 300 (47223) 380 (47278) 456(47322) 514 (47380) 146(47078) 217(45789) 301 (47254) 381 (45793) 458 (47394) 515 (47325) 147 (47033) 218(47114) 304 (47242) 382 (47301) 459(47201) 516 (47326) 149 (47094) 219 (47086) 307 (47208) 385 (47317) 460 (47343) 518 (47417) 151(47005) 220 (47104) 308 (47116) 386 (47257) 461 (47332) 519 (47381) 152 (47009) 221(47105) 309 (47250) 387 (47258) 462 (47306) 520 (47431) 154 (47039) 222 (47092) 310 (47255) 394 (45847) 463 (47307) 522 (47373) 156(47015) 223 (47062) 311 (47193) 395 (47230) 464 (47346) 523 (47374) March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 9 McDonnell Douglas Corporation Proprietary Information. Use or diaclosure of ### Page 11 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN FUS (FSN) FUS (FSN) FUS (ESN) FUS (FSN) FUS (FSN) EUS (FSN) 524 (47442) 578 (47444) 635 (47520) 692 (47581) 750 (47643) 804 (47693) 525 (47432) 579 (47455) 636 (47397) 694 (47573) 751 (47615) 805 (47694) 526 (47433) 580 (47456) 637 (47539) 695 (47571) 752 (47633) 806 (47695) 527 (47488) 583 (47517) 638(47531) 696(47584) 754 (47635) 807 (47659) 528 (47489) 584 (47465) 639 (47549) 697 (47583) 755 (47646) 808 (47696) 529 (47369) 585 (47445) 640 (47552) 698 (47585) 756 (47634) 809 (47698) 530 (47366) 586 (47505) 641 (47533) 699(47588) 757 (47654) 810 (47660) 531 (47375) 589 (47425) 642 (47553) 700 (47587) 759 (47616) 811 (47700) 532 (47429) 590 (47469) 643 (47509) 701 (47582) 760 (47653) 812 (47661) 533 (47417) 591 (47470) 644 (47534) 702 (47578) 761 (47648) 813 (47708) 534 (47412) 593 (47523) 645 (47510) 703 (47590) 762 (47617) 814 (47709) 535 (47450) 594 (47507) 646(47458) 704 (47580) 763 (47655) 815 (47712) 537 (47434) 595 (47508) 647 (47467) 705 (47593) 764 (47618) 816 (47697) 538 (47383) 596 (47472) 648 (47484) 706 (47591) 765 (47668) 817 (47702) 539 (47367) 597 (47280) 650 (47471) 707 (47586) 767 (47644) 818 (47710) 540 (47435) 598 (47473) 651 (47504) (ALLY) 80L 768 (47619) 819 (47704) 541 (47436) 599 (47491) 652 (47542) (SLY) 60L 769 (47670) 820 (47713) 542 (47385) 600 (47474) 653 (47475) (0090 12 771 (47650) 821 (47706) 544 (47437) 601 (47494) 654 (47543) (680 11L 772 (47666) 822 (47701) 545 (47438) 602 (47419) 656 (47495) 773 (47647) 823 (47707) 547 (47451) 603 (47526) 657 (47556) 774 (47671) 824 (47714) 548 (47448) 604 (47497) 659 (47536) 775 (47664) 825 (47715) 549 (47459) 605 (47479) 660 (47452) (665 912 776 (47669) 826 (47722) 550 (47386) 606 (47522) 662 (47537) (+65LY) LIL 777 (47620) 827 (47736) 551 (47370) 607 (47480) 663 (47461) (2090) 814 778 (47672) 828 (47730) 552 (47449) 609 (47430) 665 (47538) 720 779 (47673) 829 (47737) 553 (47487) 610 (47535) 667 (47555) 20918) 122 780 (47651) 830 (47738) 554 (47404) 611 (47468) 668 (47540) ZZL 781 (47680) 831 (47725) 555 (47395) 612 (47478) 669 (47428). EZL (609L7) 782 (47675) 832 (47716) 556 (47420) 613 (47477) 670 (47541) (509L) 783 (47656) 833 (47717) 557 (47396) 614 (47518) 671 (47545) 784(47681) 834 (47718) 558 (47421) 615 (47519) 672 (47559) 785 (47676) 835 (47740) 559 (47492) 616 (47481) 673 (47496) 821 (ELE) 786 (47684) 837 (47744) 560 (47490) 617 (47528) 675 (47565) 787 (47657) 838 (47723) 561 (47446) 618 (47527) 676 (47544) 731 (47637) 788 (47682) 839 (47747) 562 (47493) 619(47514) 677 (47511) 732 (47608) 789 (47678) 840 (47691) 563 (47447) 621 (47466) 678 (47512) 733 (47624) 790 (47658) 841 (47703) 564 (47462) 622 (47547) 679 (47513) 734 (47640) 791 (47677) 842 (47705) 565(47453) 623. (47550) 680 (47575) 736 (47612) 792 (47683) 843(47690) 566 (47498) 624 (47530) 681 (47564) 738(47626) 793 (47674) 844(47711) 567 (47454) 625 (47529) 682 (47576) 739 (47627) 794 (47685) 845(47719) 568 (47499) 626 (47532) 683 (47569) 740 (47628) 795 (47687) 846 (47720) 569 (47476) 627 (47460) 684 (47570) 742 (47613) 796(47665) 847(47721) 570 (47418) 628 (47486) 685 (47562) 743 (47631) 797 (47679) 848 (47727) 571(47501) 629 (47521) 686 (47577) 744 (47629) 798(47652) 849 (47726) 572 (47426) 630 (47516) 687 (47563) 745(47630) 799 (47688) 850 (47662) 573 (47427) 631 (47525) 688 (47567) 746 (47641) 800(47686) 851 (47663) 574(47502) 632 (47524) 689 (47568) 747 (47614) 801(47699) 852 (47739) 575 (47464) 633 (47548) 690 (47574) 748 (47632) 802 (47689) 853 (47724) 577 (47443) 634 (47551) 691 (47566) 749 (47642) 803 (47692) 854 (47729) Bulletin A53-232 March 28/90 Page 10 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 12 (OCR) ALERT _ DoUGLAS AIRcRAFT cOMPANY ALERT SERVICE BULLETIN FUS (FSN) EUS (ESN) FUS (FSN) FUS (FSN) EUS (ESN) FUS (FSN) 855 (47748) 905 (47786) 956 (48132) 1008 (48041) 1058 (48159) 1108(49160) 856 (47754) 906 (47789) 957 (48005) 1009 (48042) 1059 (48097) 1109 (49161) 857(47742) 907 (47790) 958 (48017) 1010 (48043) 1060 (48098) 1110 (49162) 858 (47728) 908 (47791) 959 (48133) 1011 (48072) 1061 (49116) 1111 (49163) 859 (47743) 909 (48000) 960 (48026) 1012 (48056) 1062 (49110) 1112 (49171) 860 (47731) 910 (47792) 961 (48127) 1013 (48014) 1063 (49117) 1113 (49172) 861 (47732) 911 (47793) 962(48030) 1014 (48150) 1064 (49111) 1114 (49173) 862 (47733) 912 (47787) 963 (48036) 1015 (48062) 1065 (49118) 1115 (49174) 863 (47745) 913 (47797) 964(48128) 1016 (48079) 1066 (49114) 1116 (49175) 864 (47746) 914 (47798) 965 (48037) 1017 (48151) 1067 (48099) 1117 (49165) 865(47749) 915(47794) 966 (48006) 1018 (48073) 1068 (49112) 1118(49169) 866 (47751) 916 (47795) 967 (48044) 1019 (48066) 1069 (49113) 1119 (49170) 867 (47753) 918 (47799) 968 (48129) 1020 (48063) 1070 (49119) 1120 (49176) 868 (47734) 919 (48114) 969(48031) 1021 (48138) 1071 (49120) 1121 (49177) 869 (47735) 920(48115) 970 (48045) 1022 (48080) 1072 (49121) 1122 (49178) 870 (47750) 921(48116) 971 (48007) 1023 (48057) 1073 (49122) 1123 (49179) 871 (47759) 922 (48117) 972 (48122) 1024 (48139) 1074 (49125) 1124 (49180) 872 (47752) 923 (48111) 973 (48027) 1025 (49100) 1075 (49123) 1125 (49181) 873 (47756) 924 (48015) 974(48052) 1026 (48074) 1076 (49102) 1126(49192) 874 (47760) 925 (48103) 975(48051) 1027 (48140) 1077 (49124) 1127 (49193) 875 (47761) 926(48112) 976(48130) 1028 (48067) 1078 (48021) 1128(49182) 876 (47762) 927 (48100) 977 (48046) 1029 (48086) 1079 (48022) 1129 (49183) 877 (47757) 928 (48104) 978 (48032) 1030 (48141) 1080 (49126) 1130 (49194) 878 (47755) 929 (48105) 979 (48028) 1031(48068) 1081 (48165) 1131 (49184) 879 (47763) 930 (48113) 980 (48134) 1032 (48069) 1082 • (49127) 1132(49185) 880 (47758) 931 (48101) 981 (48008) 1033 (48142) 1083 (49103) 1133 (49186) 881 (47769) 932 (48102) 982 (48137) 1034(48092) 1084 (48166) 1134 (49187) 882 (47764) 933(48106) 983 (48049) 1035 (48087) 1085 (49104) 1135 (49115) 883 (47771) 934(48123) 984 (48148) 1036 (48143) 1086 (49149) 1136(49195) 884 (47774) 935(48121) 985 (48009) 1037 (48088) 1087 (49150) 1137 (49196) 885 (47767) 936 (48107) 986 (48053) 1038(48089) 1088 (49151) 1138 (49197) 886(47766) 937 (48108) 987 (48135) 1039 (48144) 1089 (49152) 1139(49222) 887 (47768) 938 (48002) 988 (48033) 1040 (48090) 1090 (49138) 1140 (49229) 888 (47775) 939 (48109) 990 (48149) 1041 (48091) 1091 (49139) 1141(49230) 889 (47776) 940 (48131) 991 (48058) 1042 (48145) 1092 (49140) 1142(49198) 890 (47772) 941(48016) 992 (48010) 1043 (48083) 1093 (49141) 1143 (49199) 891 (47773) 942(48118) 993 (48136) 1044 (48146) 1094 (49142) 1144 (49237) 892(47770) 943 (48119) 994 (48011) 1045 (48020) 1095 (49143) 1145 (49245) 893 (47782) 944(48003) 995 (48018) 1046 (48154) 1096 (49144) 1146(49246) 894(47780) 945 (48110) 996 (48054) 1047 (48059) 1097 (49145) 1147 (49200) 895(47781) 946(48034) 997 (48012) 1048(48147) 1098 (49166) 1148(49201) 896 (47777) 947 (48125) 999 (48070) 1049 (48093) 1099 (49167) 1149 (49249) 897 (47778) 948 (48024) 7000 (48013) 1050 (48155) 1100 (49168) 1150(49260) 898(47779) 949(48120) 1001 (48019) 1051(49101) 1101(49153) 7151 (49247) 899 (47783) 950 (48004) 1002 (48038) 1052(48156) 1102 (49154) 1152 (49248) 900(47765) 951 (48126) 1003 (48039) 1053 (48094) 1103 (49155) 1153(49261) 901(47788) 952 (48025) 1004 (48071) 1054 (48157) 1104 (49156) 1154(49251) 902 (47784) 953 (48029) 1005 (48048) 1055 (48095) 1105 (49157) 1155 (49253) 903 (47796) 954 (48124) 1006 (48040) 1056 (48158) 1106 (49158) 1156 (49254) 904 (47785) 955 (48035) 1007 (48055) 1057 (48096) 1107 (49159) 1157 (49255) March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 11 McDonnall Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 13 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN FUS (FSN) EUS (ESN FUS (FSN) FUS (FSN) FUS (FSN) FUS (ESN) 1158(49256) 11.84 (49205) 1210 (49291) 1235 (49236) 1260 (49415) 1285 (49394) 1159(49262) 1185 (49265) 1211 (49292) 1236 (49383) 1261 (49402) T286 (49395) 1160 (49257) 1186 (49250) 1212 (49293) 1237 (49384) 1262 (49216) 1287 (49386) 1161 (49258) 1187 (49288) 1213(49294) 1238 (49266) 1263 (49421) 1288 (49387) 1162(49259) 1188 (49206) 1214 (49295) 1239 (49267) 1264 (49422) 1289 (49324) 1163 (49263) 1189 (49207) 1215 (49296) 1240 (49425) 1265 (49318) 1290 (49325) 1164(49269) 1190 (49208) 1216 (49297) 1241 (49428) 1266 (49319) 1291 (49443) 1165 (49270) 1191 (49209) 1217 (49298) 1242 (49429) 1267 (49320) 1292(49501) 1166 (49271) 1192 (49210) 1218 (49299) 1243 (49213) 1268 (49217) 1293 (49478) 1167 (49272) 1193 (49289) 1219 (49300) 1244 (49385) 1269 (49390) 1294 (49358) 1168 (49273) 1194(49280) 1220 (49301) 1245 (49214) 1270 (49391) 1295(49326) 1169 (49252) 1195(49290) 1221 (49302) 1246 (49309) 1271 (49416) 1296 (49327) 1170 (49202) 1196 (49366) 1222 (49303) 1247 (49310) 1272 (49392) • 1297 (49479) 1171 (49264) 1197 (49367) 1223 (49304) 1248 (49311) 1273 (49321) 1298 (49480) 1172 (49188) 1198 (49368) 1224 (49355) 1249 (49312) 1274 (49218) 1299 (49283) 1174 1173 (49189) (49203) 1199(49369) 1200 (49281) 1225 1226 (49380) (49305) 1251 1250 (49356) 1275 (49363) 1300 (49502) (49357) 1276 (49364) 1301 (49328) 1175(49286) 1201 (49373) 1227 (49306) 1252 (49372) 1277 (49365) 1302 (49329) 1176 (49287) 1202 (49211) 1228 (49307) 1253 (49215) 1278 (49417) 1303 (49436) 1177 (49231) 1203 (49233) 1229 (49308) 1254 (49420) 1279 (49393) 1304 (49440) 1178 (49232) 1204(49234) 1230 (49279) 1255 (49313) 1280 (49322) 1305 (49396) 1179 (49204) 1205 (49379) 1231 (49381) 1256 (49314) 1281 (49323) 1306 (49331) 1180(49190) 1206 (49370) 1232 (49382) 1257 (49315) 1282 (49282) 1307 (49332) 181 (49277) 1207 (49371) 1233 (49212) 1258 (49316) 1283 (49423) 1308 (49481) 1182 (49164) 1208 (49374) 1183 (49278) 1209 (49284) 1234 (49235) 1259 (49317) 1284 (49424) 1309 (49482) This modification will be incorporated prior to delivery on all applicable DC-9, Series MD-80; MD-88 aircraft, manufacturer's fuselage number 1310 and subsequent. (2) Spares Affected: None. B. Reason: Eight operators have reported cracks in the ventral aft pressure bulkhead attach tee sections on eight aircraft. The affected aircraft had accumulated between 45,492 and 60,969 landings when the cracks were found. The predominate areas of cracks are at the upper pylon attach angle between longerons 13 and 14 (6 cases) and lower pylon attach angle between longerons 16 and 17 (2 cases). Longerons 2, 7, 11, and 18 each had one crack. The cracks exhibited similar behavior, cracking circumferentially approximately l.9 inches outboard of the inboard edge of the upstanding leg of the bulkhead attach tee sections. Cracks were found up to 8.8 inches in length. Analysis of failed parts revealed that the cracks initiated at multiple sites on the forward surface of the upstanding leg of the tee as the result of fatigue due primarily to bending loads. If cracks are not detected and repaired, they could progress to the point that rapid decompression could occur. Inspection of high cycle aircraft and accomplishment of repairs based on condition will allow continued flight operation. Bulletin A53-232 March 28/90 Page 12 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Infomation. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 14 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN C. Description: This Service Bulletin accomplishes the following on the fuselage aft pressure bulkhead. Option I (Inspection from aft side of bulkhead) Performs visual and low frequency eddy current inspections for cracked aft pressure bulkhead web-to-fuselage tee sections around entire periphery of the fuselage from aft side of bulkhead and accomplishes the following: Condition 1 (No Crack) Repetitively visually and low frequency eddy current inspects for cracks from aft side of bulkhead at intervals specified in Compliance paragraph. Condition 2 (Crack) Replaces cracked tee section with new like or improved part and repetitively visually and low frequency eddy current inspects for cracks from aft side of bulkhead at intervals specified in Compliance paragraph. Option II (Inspection from forward side of bulkhead) Performs high and low frequency eddy current inspections for cracked aft pressure bulkhead web-to-fuselage tee sections around the entire periphery of the fuselage from the forward side of the bulkhead and accomplishes the following: Condition 1 (No crack) Repetitively high and low frequency eddy current inspects for cracks from forward side of bulkhead at intervals specified in Compliance paragraph. Condition 2 (Crack) Replaces cracked tee section with new like or improved part and paragraph. from forward side of bulkhead at intervals specified in Compliance repetitively high and low frequency eddy current inspects for cracks NOTE: Replacement of all six aft pressure bulkhead tee sections with new improved parts constitutes closing action for the repetitive inspection requirements of this Alert Service Bulletin. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 13 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE I FGEND ON TITI E PAGE OR FIRST PAGE ### Page 15 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN D. Compliance: It is recommended that initial inspection/repair of aft pressure bulkhead tee per Option I or II be accomplished as follows on aircraft having logged over 35,000 landings. Accumulated Landings Initial Inspection 35,000 to 49,999 Within 1500 landings from issue date of this Service Bulletin. 50,000 to 59,999 Within 1000 landings from issue date of this Service Bulletin. 60,000 and over Within 300 landings from issue date of this Service Bulletin. When aft pressure bulkhead tee section is replaced with new like part, the repetitive inspection for that section of tee may be discontinued until the aircraft has accumulated an additional 35,000 landings at which time the repetitive inspection for that section of tee are reinstated along with the ongoing repetitive inspections of the remaining original sections of tee. When aft pressure bulkhead tee section is replaced with new improved part per this Service Bulletin, the repetitive inspection for that section of tee may be discontinued as this constitutes closing action for that section of tee. Perform the recommended Option I or Option II repetitive inspections on the remaining original tee sections. Replacement of all six aft pressure bulkhead tee sections with new improved parts per this Alert Service Bulletin constitutes closing action for the inspection requirements of this Alert Service Bulletin. It is recommended that repetitive inspection/repair of aft pressure bulkhead tee be accomplished per Option I or II as follows: Option I (Inspection from aft side of bulkhead) It is recommended that repetitive low frequency eddy current inspection for cracks of side areas above floor between longerons 7 and 17 on exceed 1500 landings. fuselage left and right sides, be accomplished at intervals not to It is recommended that repetitive visual inspection for cracks of top and lower areas from longeron 7 left side to longeron 7 right side, and lower fuselage longeron 17 to longeron 20 on fuselage left and right sides, be accomplished at intervals not to exceed 1500 landings. Bulletin A53-232 March 28/90 Page 14 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 16 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN It is recommended that repetitive visual inspection for cracks of bottom areas from longeron 20 left side to longeron 20 right side, be accomplished at intervals not to exceed 3500 landings. It is recommended that cracked tee section be replaced prior to further pressurized flight. Option II (Inspection from forward side of bulkhead) It is recommended that repetitive high and low frequency eddy current inspection for cracks around entire periphery of fuselage from forward side of bulkhead be accomplished at intervals not to exceed 2500 landings. It is recommended that cracked tee section be replaced prior to further pressurized flight. E. Approval: The resultant modification described in paragraph 1.C has been shown to comply with the applicable Federal Aviation Regulations and Revision 2 is approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region, on April 28, 1995, and is approved as an Directive 89-16-12. alternate means of compliance with paragraphs A and B of Airworthiness F. Manpower: NOTE: Man-hours are estimated based on work to be performed by skilled personnel on aircraft/unit which has been placed in a maintenance status. Only actual work performed on aircraft/unit is accounted for in man-hour estimates. No man-hours have been estimated to perform the following or other incidental work required to accomplish this Service Bulletin: 1. Preparation for the modification: Examples; defueling, purging, placing work stands, opening standard access doors, obtaining tools, and jacking when not essential to the modification. 2. Nonproductive elapsed time: Examples; sealant or adhesive cure time, cleaning, paint drying time, lunch and/or rest periods, and quality assurance inspections. 3. Administrative functions: Examples; planning, engineering liaison, parts requisition, shift change coordination, and report writing. Operators should take the above into consideration when scheduling this modification. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 15 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGF. ### Page 17 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Option I (Inspection from aft side of bulkhead) Optically aided visual inspection from the aft side of the fuselage aft pressure bulkhead may be accomplished in approximately 22.0 man-hours or 11.0 elapsed hours per aircraft. Low frequency eddy current inspection from the aft side of the fuselage aft pressure bulkhead may be accomplished in approximately 11.5 man-hours or 5.8 elapsed hours per aircraft. Man-hours do not include time for fabrication of flexible borescope guide tube. Option II (Inspection from forward side of bulkhead) Removal and reinstallation of lavatories, equipment, and sealant for access to the forward side of the fuselage aft pressure bulkhead tee *an our or 5239 diased may be accomplished in approximately 140.1 man-hours or 52.9 elapsed hours per aircraft. High and low frequency eddy current inspection from the forward side of the fuselage aft pressure bulkhead may be accomplished in approximately 8.0 man-hours or 4.0 elapsed hours per aircraft. Man-hours do not include time for fabrication of eddy current reference standard. Maximum total man-hours and elapsed hours are given for inspection per aircraft. Actual man-hours and elapsed hours for repair are contingent upon inspection findings and are to be estimated by the operator. G. Material - Cost and Availability: Aircraft: Parts and materials required to accomplish this modification are listed in paragraph 3.A and are to be procured as indicated. Parts bearing Douglas Aircraft Company part numbers are proprietary parts and must be procured under the spare parts article of the purchase agreement, unless methods of manufacture are shown. Cost and availability of parts are to be negotiated between the operator and Douglas Aircraft Company. Reference this Service Bulletin number and direct inquiries to: Douglas Aircraft Company P.O. Box 1771 Long Beach, California 90801 Attn: Parts Sales - Commercial 35-12 (DC-9 Alert Service Bulletin A53-232) (2) Spares: Not applicable. Bulletin A53-232 March 28/90 Page 16 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 18 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN H. Tooling - Price and Availability: Option I (Inspection from aft side of bulkhead) (1) Special test equipment is required to accomplish the low frequency eddy current inspection per Option I outlined in this Service Bulletin. Special test equipment is to be procured from operator's stock, or sources indicated in paragraph 3.C. (2) Douglas eddy current reference standard shown in Figure 2 and listed in paragraph 3.C is required to accomplish low frequency eddy current inspection per Option I and will be made available to the operator at no charge. Procurement and availability of SB09530231-9 eddy current reference standard should be negotiated between the operator and the Douglas Aircraft Company. Specify this Service Bulletin number and direct inquiries to: Douglas Aircraft Company 910 East 236th Street Carson, California 92805 Attn: Group Leader - Recovery and Modification Services 35-35 (DC-9 Alert Service Bulletin A53-232) Option II (Inspection from forward side of bulkhead) (3) Test equipment required to accomplish high and low frequency eddy current inspections per Option II is listed in service sketch 3683D. Choice of test. equipment is at operator's option and is to be procured from operator's stock or sources indicated in service sketch 3683D. (4) Reference standard required to accomplish high and low frequency eddy current inspections per Option II is shown in service sketch 3683D. Reference standard may be procured from operator's stock, fabricated by the operator, or purchased from source indicated in paragraph 3.D. I. Weight and Balance: Weight change at appropriate fuselage stations by incorporation of any part of this Service Bulletin is contingent upon the modification of each particular aircraft. weight data is to be computed by the operator by weighing parts installed and parts removed during modification. Necessary revisions should be made to the appropriate - weight and balance document. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 17 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI F PAGF OR FIRST PAGE ### Page 19 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN J. References: Federal Aviation Administration Airworthiness Directive No. 89-16-12: Amendment 39-6287, effective September 7, 1989. (2) Alert Service Bulletins A53-147 and A53-191. (3) Data used in preparation of this Alert Service Bulletin: Data Identification Change Type of Data DMS 2082 Douglas Material Specification J060157 Service Rework Shoring J060157 B Advance E.O. MM Chapters 6, 20, Maintenance Manual 21, 25, 26, 36, 49, 52, and 53 NDT Chapter 1-3 Nondestructive Testing Manual SRM Chapters 51 and 53 Structural Repair Manual SR09530001 C Service Rework Drawing SR09530001 D Advance E.O. SR09530048 New Service Rework Drawing SR09530056 C Service Rework Drawing SR09530056 D Advance E.O. SR09530083 New Service Rework Drawing 3683D Service Sketch (attached) 5910130 DY Drawing 5930760 AM Drawing (4) Data supplied in support of this Alert Service Bulletin: Data Identification Change Type of Data J060157 Service Rework Shoring J060157 B Advance E.O. SR09530001 C Service Rework Drawing SR09530001 D Advance E.O. SR09530048 New Service Rework Drawing SRO9530056 C Service Rework Drawing SR09530056 D Advance E.O. SRO9530083 New Service Rework Drawing NOTE: Listed data are being furnished to each affected operator. K. Publications Affected: The modification outlined in this Service Bulletin affects the DC-9 Weight and Balance Documents. L. Electrical Load Data: Not affected. M. Software Accomplishment Summary: Not affected. Bulletin A53-232 March 28/90 Page 18 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or discloure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 20 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN 2. Accomplishment Instructions: WARNING: TO AVOID INJURY TO MAINTENANCE PERSONNEL OR DAMAGE TO EQUIPMENT, MAKE CERTAIN ADEQUATE PRECAUTIONS ARE TAKEN WHILE PERFORMING ANY WORK IF ELECTRICAL POWER IS APPLIED TO THE AIRCRAFT. CAUTION: ELECTRICALLY GROUND THE AIRCRAFT. GENERAL NOTES: 1. Replacement of all six aft pressure bulkhead tee sections with new improved parts constitutes closing action for the repetitive inspection requirements of this Alert Service Bulletin. If replacing all six aft pressure bulkhead tee sections, replacement should be accomplished one tee section at a time. Refer to sections of the Maintenance Manual (MM), Structural Repair Manual (SRM), and Non-Destructive Testing Manual (NDT). 3. Refer to the following manual chapters for applicable operations: Manual Chapter Operation MM 20-30-0 Sealant Application NOT 1-3 Eddy Current Inspection SRM 51-10-4 Drilling And Countersinking SRM SRM 51-30-2 51-30-1 . Removing And Installing Rivets Installing Bolts, Screws, and Washers SRM 51-30-3 Removing And Installing Lockbolts SRM 51-30-5 Removing And Installing Pins 4. For approved fastener and process material substitutions, see DC-9 SRM chapter 51-60-0, paragraph entitled "Interchangeability of Fasteners" and "Interchangeability of Materials." 5. If the length of the fasteners specified in this Service Bulletin do not meet acceptable installation standards, fasteners of the same type, or approved substitutions, one increment longer or shorter in length may be used. 6. A combined total of two (maximum) 1/16-inch thick washers or four (maximum) 1/32-inch thick washers or any combination thereof not exceeding 1/8-inch total stackup thickness of the washer types called for in this Service Bulletin may be used under fastener head or nut to counteract accumulation of tolerances. If substitutions are used other than those in Douglas approved publications, operator must obtain FAA approval from local authorized agency. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 19 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI F PAGF OR FIRST PAGF ### Page 21 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Option I (Inspection from aft side of bulkhead) A. Operator's Option - Access doors may be installed in skin on bottom of fuselage forward of auxiliary power unit (APU) door per service rework drawing SR09530048 to facilitate inspection. B. Operator's Option - Fabricate guide tube (to be used with flexiscope) from flexible or thin wall tubing to fit outside diameter of flexiscope as shown on Figure 1. C. Operator's option - Fabricate reference standard as shown on Figure 2. D. Gain access to inspection areas on aft side of bulkhead by opening or removing and retaining the following access doors/panels as applicable to accomplish visual and/or low frequency eddy current inspection: AcceSS NO. Access Area MM Chapter 5806A Auxiliary Exit Door, 6-12-0 Non-Ventral Bulkhead 5901A Thrust Reverser Control 6-11-4 Valve (Left Side) 5902A Thrust Reverser Control 6-11-4 Valve (Right Side) 5903A APU Service (Left Side) 6-11-4 5904A APU Service (Right Side) 6-11-4 5910A Ventral Stair Ceiling 6-12-0 5911A Ventral Stair (Right Side) 6-12-0 5912A Ventral Stair (Left Side) 6-12-0 NOTE: The following paragraphs 2.D through 2.H may be accomplished at operator's option and are applicable to visual inspection requirements. E. Remove and retain APU and attaching parts. (See MM chapter 49-10-0, paragraph entitled "Removal/Installation Power Plant.") Remove and retain APU compartment enclosure and attaching parts. (See MM chapter 53-20-5, paragraph entitled "Removal/Installation APU Compartment Enclosure.") Bulletin A53-232 March 28/90 Page 20 Revision 2 April 28/95 McDonnell Douglas Corporation Propriotary Information. Use or diacloure of THESE NATA CIR IEFT TO RECTRICTIVE I FGEND ON TITLE PAGE OR FIRST PAGE. ### Page 22 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN G. Remove and retain lower firex bottle and attaching parts. (See MM chapter 26-20-1, paragraph entitled Removal/Installation Fire Extinguishing Containers.") H. Remove and retain right pneumatic crossfeed valve pushrod and attacning parts. (See мм cnapter Sb-10-3, paragrapn entitled "Removal/Installation Pneumatic Crossfeed Valve.") I. Remove and retain two upper conditioned air duct assemblies, check valves, and attaching parts aft of pressure bulkhead center ceiling. (See MM chapter 21-20-2, paragraph entitled Removal/Installation Conditioned and Cold Air Check Valve. J. Roll back or remove and retain insulation blankets from aft side of aft pressure bulkhead. (See MM chapter 25-22-0, paragraph entitled "Removal/Installation Insulation Blankets.") K. Perform optically aided visual and low frequency eddy current inspection/repair of the aft pressure bulkhead web to fuselage skin attach tee sections from the aft side of the bulkhead as follows: (1) Inspect the upstanding leg of 5910130 ventral bulkhead tee sections from aft side of bulkhead around the periphery of the bulkhead as shown on Figure 3 and accomplish the following: Condition 1 (No Crack) (2) Perform repetitive visual and/or low frequency eddy current inspections from aft side of bulkhead at intervals specified in Compliance paragraph. Condition 2 (Crack) Replace cracked tee section with new like or improved part per Figure 4 (See Table I for configuration) prior to further pressurized flight. Perform repetitive visual and/or low frequency eddy current inspections from aft side of bulkhead at intervals specified in Compliance paragraph. If any tee section is to be replaced, remove and retain engines 1 and 2. (See MM chapter 71-00-0, paragraph entitled "Removal/Installation Power Plant.") NOTE: If replacing all six aft pressure bulkhead tee sections, replacement should be accomplished one tee section at a time. (5) Shore aircraft as shown on Figure 5. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 21 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI F PAGE OR FIRST PARE ### Page 23 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN -. Record and report all results, both negative and positive of inspectior to DAC. Include fuselage number, factory serial number, crack location, Forward to: crack length, flight-hours, and accumulated landings of aircraft. Douglas Aircraft Company P.O. Box 1771 Long Beach, California 90801 Attn: Business Unit Manager Customer Services - Airframe Product Support 35-35 (DC-9 Alert Service Bulletin A53-232) M. Apply PR-1422 B-2 sealant around entire periphery of the bulkhead tee sections, as applicable. N. Reinstall retained insulation blankets on aft side of aft pressure bulkhead. (See M chapter 25-22-0, paragraph entitled "Removal/Installation Insulation Blankets." O. Reinstall right pneumatic crossfeed valve pushrod and attaching parts as applicable. (See MM chapter 36-10-3, paragraph entitled "Removal/Installation Pneumatic Crossfeed Valve.") p. Reinstall two upper conditioned air duct assemblies, check valves, and attaching parts as applicable. entitled "Removal/Installation Conditioned and Cold Air Check Valve.") (See MM chapter 21-20-2, paragrapr Q. Reinstall lower firex bottle and attaching parts as applicable. (See MM chapter 26-20-1, paragraph entitled Removal/Installation Fire Extinguishing Containers."). R. Reinstall APU compartment enclosure, as applicable. (See MM chapter 53-20-5, paragraph entitled Removal/Installation APU Compartment Enclosure.i) S. Reinstall APU and attaching parts as applicable. (See MM chapter 49-10-0, paragraph entitled "Removal/Installation Power Plant.") T. Reinstall engines 1 and 2 as applicable. (See MM chapter 71-00-0, paragraph entitled "Removal/Installation Power Plant.") U. Remove shoring as shown on Figure 5 as applicable. V. Close/reinstall access doors/panels as outlined under Option I paragraph 2.C. Bulletin A53-232 March 28/90 Page 22 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 24 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN Option II (Inspection from forward side of bulkhead) Perform high and low frequency eddy current inspections of the aft pressure bulkhead web to fuselage skin attach tee sections from the forward side of the bulkhead as follows: (1) Operator's Option - Fabricate eddy current reference standard as shown on service sketch 3683D, Figure 5. (2) Remove and retain items as outlined in service sketch 3683D, Table I, as applicable. (3) Inspect the standing leg of ventral bulkhead tee sections from forward side of bulkhead around the entire periphery of the bulkhead as shown on service sketch 3683D, and accomplish the following: Condition 1 (No Crack) Perform repetitive high and low frequency eddy current inspections from forward side of bulkhead at intervals specified in Compliance paragraph. Condition 2 (Crack) Replace cracked tee section with new like or improved part per Figure 4 (See Table I for configuration) prior to further pressurized flight. Perform repetitive high and low frequency eddy current inspections from forward side of bulkhead at intervals specified in Compliance paragraph. (4) If any tee section is to be replaced, remove and retain engines 1 and 2. (See MM chapter 71-00-0, paragraph entitled "Removal/Installation Power Plant.") Shore aircraft as shown on Figure 5. NOTE: If replacing all six aft pressure bulkhead tee sections, replacement should be accomplished one tee section at a time. Forward to: Douglas Aircraft Company P.O. Box 1771 Long Beach, California 90801 Attn: Business Unit Manager Customer Services - Airframe Product Support 35-35 (DC-9 Alert Service Bulletin A53-232) March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 23 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI F PAGE OR FIRST PAGE ### Page 25 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN C. Apply PR-1422 B-2 sealant around entire periphery of the bulkhead tee sections, as applicable. D. Retagrall engitied Removal instalfation power Mantapter 71-00-0. E. Remove shoring as shown on Figure 5 as applicable. F. Close/reinstall retained items as outlined in service sketch 3683D Table I, as applicable. Bulletin A53-232 March 28/90 Page 24 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 26 (OCR) ALERT DouGLAS aiRcraFT cOMpAnY ALERT - SERVICE BULLETIN TUBE I.D. TO FIT O. D. OF FLEXISCOPE STA X=-20.000 • FLEXISCOPE GUIDE TUBE - STA Z=-40.000 -FLEXIBILE OR THIN WALL TUBING APPROX 3 FEET DETAIL FLEXISCOPE GUIDE TUBE MAKE FROM COMMERCIAL FLEXIBLE OR THIN WALL TUBING 3/8 OR 1/2-INCH DIAMETER STA X=-10.000 - INTERCOSTAL VIEW LOOKING FORWARD RIGHT SIDE AT FRAME INSTALLATION AFT OF PRESSURE BULKHEAD ILLUSTRATION OF GUIDE TUBE USE APPROX 2-3 INCHES. FLEXIBLE BORESCOPE GUIDE TUBE - FABRICATION AND USE March 28/90 FIGURE 1 Bulletin A53-232 Revision 2 April 28/95 Page 25 McDonnail Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE ### Page 27 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN EDM NOTCH • EDM NOTCH EDM NOTCH NO. 3 NO. 2 NO. 1 - + FORWARD 1.906 IN. (34.92 MM) 1.375 IN. 1.906 IN. SURFACE (48.41 MM) (48.41 MM) - 1.000 IN. (25.40 MM) - 2.750 IN. (69.85 MM) 4.500 IN. (114.30 MM) 6.000 IN. (152.40 MM) LENGTH •DEPTH DETAIL SB09530231-9 EDDY CURRENT REFERENCE STANDARD MAKE FROM 1D0008S TEE-EXTRUDED SECTION (2024-0) HEAT TREAT TO 2024T42. GENERAL NOTES: EDM NOTCH (TYP) 1. EDM NOTCH MAXIMUM WIDTH .010-INCH (.25 MM). 2. NOTCH TO BE ON AND PERPENDICULAR TO FORWARD SURFACE. EDM NOTCH 3. SCALE NONE. - 2 3 4. THIS SB09530231-9 EDDY CURRENT REFERENCE LENGTH 1.000 1.000 1.000 STANDARD REQUIRED TO ACCOMPLISH OPTION I DEPTH 0.055 0.050 0.028 WILL BE MADE AVAILABLE BY DAC AT NO CHARGE, SEE PARAGRAPH 1.H. TOLERANCES IN. = INCHES MM = MILLIMETERS ANGLES + 0° 30' 3 PLACE DECIMAL ‡.015 IN. (0.38 MM) 2 PLACE DECIMAL ‡.03 IN. (0.8 MM) OPTION I EDDY CURRENT REFERENCE STANDARD - FABRICATION Bulletin A53-232 FIGURE 2 March 28/90 Page 26 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI E DARE nO CIDOT NA ### Page 28 (OCR) ALERT DOUGLAS AIRCRAFT cOMPANY ALERT SERVICE BULLETIN GENERAL NOTES: 1. PERFORM INSPECTION PROCEDURE A, SEQUENCES 1 THROUGH 3 BEFORE CLEANING THE TEE AND AFTER CLEANING THE TEE AS NOTED. 2. PROCEDURE A - DESCRIBES AN OPTICALLY AIDED VISUAL INSPECTION OF DC-9 AFT PRESSURE BULKHEAD WEB TO FUSELAGE SKIN ATTACH TEE SECTIONS TO DETECT FATIGUE CRACKS IN THE UPSTANDING LEG OF TEE SECTIONS. PROCEDURE B - DESCRIBES A LOW FREQUENCY EDDY CURRENT INSPECTION OF DC-9 AFT PRESSURE BULKHEAD WEB TO FUSELAGE SKIN ATTACH TEE SECTIONS TO DETECT FATIGUE CRACKS IN THE UPSTANDING LEG OF TEE SECTIONS. 4. INSPECTION OF THE BULKHEAD TEE FOR CRACKS BY PROCEDURE A OR B IS MADE FROM THE AFT SIDE OF THE AFT PRESSURE BULKHEAD. 5. INSPECTION BY PROCEDURE A IS DIVIDED INTO THREE SEQUENCES BASED ON ACCESS LOCATION. 6. INSPECTION BY PROCEDURE B IS DIVIDED INTO TWO SEQUENCES BASED ON INSPECTION PROBE DESIGN. a. INSPECTION PROCEDURE B, SEQUENCE 1, INSPECTS THE TEE ACUTE ANGLE TANGENT AREA OF THE UPSTANDING LEG OF TEE USING A MOLDED PROBE THAT CONFORMS TO THE RADIUS. b. INSPECTION PROCEDURE B, SEQUENCE 2, INSPECTS EXTENDED AREA OF UPSTANDING LEG OF TEE. AREA EXTENDS FROM THE VICINITY OF THE INBOARD ROW OF ATTACHMENTS INSTALLED THROUGH THE TEE UPSTANDING LEG AND THEN EXTENDS OUTBOARD TO AND OVERLAPS THE AREA INSPECTED IN SEQUENCE 1. INSPECTION IS MADE USING A 90 DEGREE PROBE. 7. SIGNS OF NICOTINE STAINS MAY INDICATE CRACKS. 8. THE FOLLOWING EQUIPMENT OR EQUIVALENT IS REQUIRED: SEE PARAGRAPH 3.C FOR TEST EQUIPMENT SUPPLIERS. VISUAL EQUIPMENT: a. FLASHLIGHT. b. INSPECTION MIRROR WITH ADJUSTABLE VIEWING ANGLE. ENDOSCOPE EQUIPMENT: ONE 70 OR 90 DEGREE ENDOSCOPE OF ANY DIAMETER WITH 18-INCH (457.2 MM) MINIMUM LENGTH AND LIGHT SOURCE SUCH AS: (1) ENDOSCOPE MODEL 10320D, 70 DEGREE (FOREOBLIQUE) ANGLE, 19-INCH (482.6 MM) LONG, 0.217-INCH DIAMETER. (2) FIBER OPTIC LIGHT BUNDLE MODEL 495NL. (3) ENDOSCOPE LIGHT SOURCE NUMBER 00482 (110 OR 220 VOLT) OR NUMBER E0590 (110 VOLT ONLY). (4) SYLVANIA PROJECTOR LAMP (150 WATT, 120 VOLT). AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 1 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 27 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 29 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN FLEXIBLE BORESCOPE: d. ONE FORWARD VIEWING ENDOSCOPE OF ANY DIAMETER WITH 30 INCH MINIMUM LENGTH SUCH AS: (1) OLYMPUS MODEL 1F8D3, 29.8-INCH (757 MM) LONG, 0.315-INCH DIAMETER. = (2) COLD LIGHT SUPPLY NUMBER 1LK-4 (100 TO 230 VOLT). EDDY CURRENT EQUIPMENT: e. ONE EDDY CURRENT FLAW DETECTOR WITH IMPEDANCE PLANE DISPLAY SUCH AS: STAVELEY INSTRUMENTS EDDY CURRENT INSTRUMENT, TYPE NDT-18 OR NDT-19 OR ZETEC EDDY CURRENT INSTRUMENT, MIZ-20A f. LOW FREQUENCY EDDY CURRENT PROBES SUCH AS: (1) MOLDED PROBE OPERATING BETWEEN 5 AND 50 kHz: CATALOG NUMBER 935-0120, PART NUMBER APB/MSP, ZETEC INCORPORATED; OR MODEL SPO-4080 STAVELEY INSTRUMENTS. (SEE SHEET 6.) NOTE: IF SERVICE BULLETIN 53-147 HAS BEEN ACCOMPLISHED, SUBSTITUTE STAVELEY INSTRUMENTS SPO-5222 IN PLACE OF PROBES LISTED IN PARAGRAPH F.(1). (SEE SHEET 7.) PENCIL 90 DEGREE ANGLE PROBE OPERATING BETWEEN 5 AND 50 kHZ: CRADEL SO-4081 STAVELEY INSTRUMENTS. 582E SHEET INCORPORATED; g. SB09530231-9 EDDY CURRENT REFERENCE STANDARD. AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 2 OF 17) March 28/90 Page 28 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE ### Page 30 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN - INSPECTION PROCEDURE A. VISUAL INSPECTION PROCEDURE A: SEQUENCE 1: PERFORM MIRROR/FLASHLIGHT OR ENDOSCOPE INSPECTION OF UPPER FUSELAGE TEE SECTIONS FROM LONGERON L7 LEFT SIDE TO LONGERON L7 RIGHT SIDE, LOWER FUSELAGE LONGERON LIZ LEFT SIDE TO LONGERON LZO LEFT SIDE, AND LONGERON L17 RIGHT TO LONGERON L19 RIGHT SIDE. (2) PERFORM ENDOSCOPE OR FLEXIBLE BORESCOPE INSPECTION OF LOWER FUSELAGE TEE SECTIONS FROM LONGERON L19 RIGHT SIDE TO LONGERON L20 RIGHT SIDE. SEQUENCE 2: PERFORM MIRROR/FLASHLIGHT OR ENDOSCOPE INSPECTION OF LOWER FUSELAGE TEE SECTION THROUGH THRUST REVERSER LOCKOUT ACCESS OPENING 5901A FROM LONGERON L20 LEFT SIDE TO LONGERON L23 LEFT SIDE. (2) PERFORM MIRROR/FLASHLIGHT OR ENDOSCOPE INSPECTION OF LOWER FUSELAGE TEE SECTION THROUGH THRUST REVERSER LOCKOUT ACCESS OPENING 5902A FROM LONGERON L20 RIGHT SIDE TO LONGERON L24 RIGHT SIDE. NOTE: SEQUENCE 2 AND 3 MAY BE ACCOMPLISHED USING INSPECTION MIRROR AND FLASHLIGHT IF SUFFICIENT ACCESS IS AVAILABLE. SEQUENCE 3: (1) PERFORM VISUAL INSPECTION OF LOWER FUSELAGE TEE SECTIONS WITH FLASHLIGHT FROM LONGERON L23 LEFỊ SIDE TO LONGERON L24 RIGHT SIDE. REMOVE SEALANT FROM INSPECTION AREA OF TEE SECTIONS THAT MAY HINDER INSPECTION. CLEAN DIRT, GREASE, AND ALL FOREIGN MATERIALS FROM INSPECTION AREA OF TEE SECTIONS USING LINT-FREE WIPER AND 1,1,1 TRICHLOROETHANE SOLVENT OR EQUIVALENT. PERFORM INSPECTION SEQUENCES 1 THROUGH 3 AFTER CLEANING THE TEE SECTIONS. B. LOW FREQUENCY EDDY CURRENT INSPECTION PROCEDURE B: NOTE: PROCEDURE B, LOW FREQUENCY EDDY CURRENT INSPECTION PROCEDURE IS APPLICABLE TO AREA OF TEE SECTION BETWEEN LONGERONS 17 AND L17 ON LEFT AND RIGHT SIDES OF FUSELAGE THAT ARE NOT COVERED BY SPLICE PLATES OR SHOVEL CLIPS. AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 3 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 29 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 31 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN SEQUENCE 1: (1) CALIBRATE EDDY CURRENT EQUIPMENT AS FOLLOWS: CONNECT MOLDED PROBE TO EDDY CURRENT INSTRUMENT AND SET OPERATING FREQUENCY AT 7 KHZ PER MANUFACTURER'S INSTRUCTIONS. NOTE: IF SERVICE BULLETIN 53-147 HAS BEEN ACCOMPLISHED, USE STAVELEY INSTRUMENT SPO-5222 PROBE. IF SERVICE BULLETIN 53-147 HAS NOT BEEN ACCOMPLISHED, USE MOLDED PROBE LISTED IN PARAGRAPH F.(1). SEE SHEETS 6 AND 7.) (b) PLACE MOLDED PROBE ON REFERENCE STANDARD IN AN AREA FREE FROM NOTCH OR EDGE EFFECTS. NULL/BALANCE THE INSTRUMENT AND ADJUST LIFT-OFF PER MANUFACTURER'S INSTRUCTIONS. SCAN ACROSS REFERENCE STANDARD EDM NOTCH 1 WITH MOLDED PROBE AND ADJUST SENSITIVITY AND PHASE CONTROLS TO OBTAIN A DISPLAY SIMILAR TO THAT SHOWN ON SHEET 15 FOR STANDARD PROBE OR SHEET 16 FOR MODIFIED PROBE. (2) PERFORM EDDY CURRENT INSPECTION OF AFT PRESSURE BULKHEAD TEE AS FOLLOHS: PLACE MOLDED PROBE IN THE RADIUS OF UPSTANDING LEG OF TEE AFT SIDE OF TEE, AND RENULL/BALANCE INSTRUMENT. IN AREA FREE FROM EDGE OR FASTENER EFFECTS, SCAN THE TANGENT AREA NOTE: THE MOLDED PROBE WILL NOT FIT INTO THE TEE RADIUS IN THE AREA OF LONGERON SHOVEL INSPECTED IN SEQUENCE 2 PROCEDURE. PORTIONS OF THESE AREAS WILL BE (b) PROGRESSIVELY SCAN ENTIRE LENGTH OF TEE TANGENT AREA BETWEEN LONGERONS L7 AND L17 ON FUSELAGE LEFT AND RIGHT SIDES. NOTE: ONE TECHNICIAN IS TO OPERATE THE PROBE WHILE ANOTHER TECHNICIAN EVALUATES THE EDDY CURRENT RESPONSE. THE TECHNICIAN WATCHING THE DISPLAY SHOULD PERIODICALLY ERASE LIFT-OFF TRACE TO AVOID MISSING A SMALL CRACK INDICATION. TECHNICIAN WATCHING DISPLAY MUST BE IN CONSTANT COMMUNICATION WITH TECHNICIAN OPERATING PROBE TO MAKE SURE PROBE IS MAKING GOOD CONTACT WITH TEE SECTION SURFACE. AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 4 OF 17) March 28/90 Page 30 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 32 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN SEQUENCE 2: (1) CALIBRATE EDDY CURRENT EQUIPMENT AS FOLLOWS: (a) CONNECT 90 DEGREE PROBE TO EDDY CURRENT INSTRUMENT AND SET OPERATING FREQUENCY AT 10 KHZ PER MANUFACTURER'S INSTRUCTIONS. (b) PLACE 90 DEGREE PROBE ON REFERENCE STANDARD IN AN AREA FREE FROM NOTCH OR EDGE EFFECTS. NULL/BALANCE THE INSTRUMENT AND ADJUST LIFT-OFF PER MANUFACTURER'S INSTRUCTIONS. (C) SCAN ACROSS REFERENCE STANDARD EDM NOTCH 2 WITH 90 DEGREE PROBE AND ADJUST SENSITIVITY AND PHASE CONTROLS TO OBTAIN A DISPLAY SIMILAR TO THAT SHOWN ON SHEET 17. (2) PERFORM EDDY CURRENT INSPECTION OF AFT PRESSURE BULKHEAD TEE AS FOLLOHS: PLACE 90 DEGREE PROBE ON AFT SIDE OF TEE UPSTANDING LEG IN AN AREA FREE OF FASTENER EFFECTS, SCAN AND RENULL/BALANCE INSTRUMENT. PROGRESSIVELY SCAN THE EXTENDED AREA OF THE UPSTANDING LEG OF TEE FROM THE VICINITY OF THE INBOARD ROW OF ATTACHMENTS THROUGH THE TEE UPSTANDING LEG THEN OUTBOARD TO AND OVERLAPPING THE TANGENT AREA SCANNED IN SEQUENCE 1. NOTE: SCAN ONLY THOSE AREAS WHERE THE PROBE WILL FIT EASILY IN THE AREA OF LONGERON SHOVEL CLIPS. ONE TECHNICIAN IS TO OPERATE THE PROBE WHILE ANOTHER TECHNICIAN EVALUATES THE EDDY CURRENT RESPONSE. THE TECHNICIAN WATCHING THE DISPLAY SHOULD PERIODICALLY ERASE LIFT-OFF TRACE TO AVOID MISSING A SMALL CRACK INDICATION. TECHNICIAN WATCHING DISPLAY MUST BE IN CONSTANT COMMUNICATION WITH TECHNICIAN OPERATING PROBE TO MAKE SURE PROBE IS MAKING GOOD CONTACT WITH TEE SECTION SURFACE. RAPID SCANNING OF TEE SURFACE CAN GENERATE EXCESSIVE NOISE WHICH COULD MASK A SMALL CRACK INDICATION. (c) ANY INDICATION WHICH EXHIBITS SAME RELATIVE PHASE ANGLE AND AN AMPLITUDE EQUAL TO OR GREATER THAN 50 PERCENT OF THAT OBTAINED FROM REFERENCE STANDARD IS CONSIDERED A CRACK. (a) RECORD LENGTH AND LOCATION OF EACH CRACK AND DISTANCE BETWEEN MULTIPLE CRACKS. REPORT ALL CRACK INDICATIONS TO DAC AS NOTED IN PARAGRAPH 2.K. AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 5 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 31 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 33 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN TOLERANCES IN. = INCHES MM = MILLIMETERS ANGLES + 0° 30° 3 PLACE DECIMAL ‡ .015 IN. (0.38 MM) 2 PLACE DECIMAL ‡.03 IN. (0.8 MM) •625 IN. (15.88 MM) - (7.92 MM) •312 IN. (4.75 MM) •187 IN. SIDE VIEW •562 IN.- (14.27 MM) •687 IN. (17.45 MM) •812 IN. (20.62 MM) •375 IN. (9.52 MM) ZETEC INCORPORATED C/N 935-0120 P/N APB/MSP LOW FREQUENCY EDDY CURRENT PROBE OR EQUIVALENT AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 6 OF 17) March 28/90 Page 32 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 34 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN TOLERANCES IN. = INCHES MM = MILLIMETERS ANGLES + 0° 30' 3 PLACE DECIMAL ‡ .015 IN. (0.38 MM) 2 PLACE DECIMAL ‡ .03 IN. (0.8 MM) EXCEPT SPECIFIED TOLERANCES SHOWN .203 IN. RADIUS .062 IN. .187 IN. (5.16 MM) (9.52 MM) .375 IN. RADIUS .234 IN. -.687 IN.→ (5.94 MM) (17.45 MM) (15.88 MM) .. • 625 IN.- . 187 IN. (4.75 MM) .843 IN. (21.41 MM) REFLECTANCE COIL PLACEMENT .281 IN. (7.14 MM) SPO-5222 OR EQUIVALENT AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 7 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 33 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 35 (OCR) ALERT DoUGLAS AIRCRAFT cOMPANY ALERT SERVICE BULLETIN •250 IN. DIA COIL •300 IN. (7.62 MM) 4.00 IN. (101.6 MM) ZETEC INCORPORATED C/N 910-5830 P/N APB/90DP LOW FREQUENCY EDDY CURRENT PROBE OR EQUIVALENT AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 8 OF 17) March 28/90 Page 34 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 36 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN FUSELAGE LONGERON NUMBERING VIEW LOOKING FORWARD AT AFT PRESSURE BULKHEAD TEE 212 00 10 10,13 12. •12 13 - 13 14- -14 15 : 15 16° — 16 1í8- ~ 1817 19 20 2019 *ENDOSCOPE OR FLEXISCOPE ... INSPECTION SEQUENCE 1 FUSELAGE CUSP LINE 20- 2221 23 INSPECTION SEQUENCE 2 FUSELAGE .CUSP LINE 23 24 26/28/30|28 26 25 27 29 29 27 24 INSPECTION SEQUENCE 3 VISUAL INSPECTION PROCEDURE A SEQUENCES FOR AFT PRESSURE BULKHEAD TEE AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 9 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 35 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 37 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN FUSELAGE LONGERON NUMBERING VIEW LOOKING FORWARD AT AFT PRESSURE BULKHEAD TEE 9. < 10_11 - 13 15 - 15 17 LOW FREQUENCY EDDY CURRENT INSPECTION AREAS OF AFT PRESSURE BULKHEAD FOR PROCEDURE B AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 10 OF 17) March 28/90 Page 36 Revision 2 April 28/95 McDonnell Douglas Corporation Propristary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 38 (OCR) ALERT DOUGLAS AIRCRAFT cOMPANY ALERT SERVICE BULLETIN 5910130-51 OR 5910130-389 TEE LI LE L3 S L6 L8 Z=74 5910130-53 L9 L10 OR LIO +2=63 5910130-54 5910130-391 TEE 111 _L11 OR L12 - L12 5910130-392 - 2=48 TEE L13- _L13 LL UPPER LI4 2=34 PYLON L15- • 2=24 LL UPPER -L16 PYLON FRP ' S ~119 L19 \ L20 5910130-55 L21' L20 L21 5910130-56 OR OR L22 5910130-394 5910130-393 L22 TEE TEE L23 L24 L25 124 L23 L25 →L26 127126 LZ7 L28 L29 L30 L29 L28 5910130-47 OR FRP = FUSELAGE REFERENCE PLANE 5910130-387 LL = LOFT LINE TEE = PRODUCTION SPLICE Z = STATION VIEW LOOKING FORWARD DC-9 VENTRAL AFT PRESSURE BULKHEAD SCHEMATIC DIAGRAM SHOWING TEE LOCATIONS AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 11 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 37 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 39 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN ANGLE - 5910130 BULKHEAD TEE FWD - VISUAL INSPECTION INBD AREA CRACK - 70° OR 90° ENDOSCOPE DETAIL A - ENDOSCOPE VISUAL INSPECTION - ANGLE — CRACK - VISUAL 5910130 INSPECTION BULKHEAD AREA TEE - - WEB INSPECTION MIRROR- - FLASHLIGHT DETAIL B - MIRROR FLASHLIGHT VISUAL INSPECTION SEQUENCE 1 VISUAL AND ENDSCOPE INSPECTION OF BULKHEAD TEE AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 12 OF 17) March 28/90 'age 38 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE I PRELIM - ### Page 40 (OCR) ALERT DOUGLAS AIRCRAFT cOMPANY ALERT SERVICE BULLETIN LOOKING FORWARD TEE TEE SPLICE PLATE- CRACK CRACK WEB WEB oUTBD| FWD ANGLE• SECTION A-A SECTION B-B DC-9 VENTRAL AFT PRESSURE BULKHEAD. TEE CAP CRACKS AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 13 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 39 McDonnell Douglas Corporation Propristary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 41 (OCR) ALERT DouGLAs aiRcRAFT coMpANY ALERT SERVICE BULLETIN LFEC INSPECT THIS SURFACE USING MOLDED — WEB PROBE •LFEC INSPECT THIS SURFACE AS SHOWN BELOW USING 90 DEGREE PROBE - START OF RADIUS Vovovovovorovovove SCANNING PATTERN FOR LFEC INSPECTION OF SUBJECT SURFACE USING 90 DEGREE PROBE INSPECTION AREA ON TEE AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 14 OF 17) March 28/90 Page 40 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PARF ### Page 42 (OCR) ALERT DouGLAS AIRcRAFT cOMPANY ALERT SERVICE BULLETIN EDM NOTCH NO. 3 EDM NOTCH EDM NOTCH (NOT USED) NO. 2 NO. 1 SB09530231-9 REFERENCE STANDARD STANDARD MOLDED CALIBRATION PROCEDURE FOR SEQUENCE 1 PROBE CRACK INSTRUMENT - NDT-18 PROBE - ZETEC C/N 935-0120 P/N APB/MSP FREQUENCY - 7 kHz GAIN - 32dB VERTICAL - 0.2 HORIZONTAL - 2.0 ROTATION - 9:00 FILTER - OFF NOTE: SETTINGS LISTED WERE USED TO DEVELOP PROCEDURE. VALUES MAY VARY FROM INSTRUMENT TO INSTRUMENT LIFT-OFF NO CRACK SCOPE PRESENTATION AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 15 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 41 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 43 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN EDM NOTCH NO. 3 EDM NOTCH • EDM NOTCH (NOT USED) NO. 2 NO. 1 SB09530231-9 REFERENCE STANDARD MODIFIED MOLDED PROBE WITH MODIFIED PROBE AFTER SB 53-147 CALIBRATION PROCEDURE FOR SEQUENCE 1 SPO-5222 OR EQUIVALENT HAS BEEN ACCOMPLISHED NO CRACK - CRACK ‡ INSTRUMENT - NDT-18 PROBE - SPO-5222 FREQUENCY - 7 kHz GAIN - 35dB VERTICAL - 0.2 HORIZONTAL - 2.0 ROTATION - 8:00 FILTER - OFF NOTE: SETTINGS LISTED WERE USED TO DEVELOP PROCEDURE. VALUES MAY VARY FROM INSTRUMENT TO INSTRUMENT • LIFT-OFF AFT PRESSURE BULKHEAD TEE - INSPECTION Bulletin A53-232 FIGURE 3 (SHEET 16 OF 17) March 28/90 Page 42 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI F PAGE OF EIDCT DARE ### Page 44 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN EDM NOTCH • EDM NOTCH - EDM NOTCH NO. 3 (NOT USED) NO. 2 NO. 1 -SB09530231-9 REFERENCE STANDARD 90° PROBE - CALIBRATION PROCEDURE FOR SEQUENCE 2 • CRACK INSTRUMENT - NDT-18 PROBE - ZETEC C/N 910-583 P/N APB/ 90DP FREQUENCY - 10 kHz GAIN - 3508 NO CRACK VERTICAL - 0.2 HORIZONTAL - 2.0 ROTATION - 7:30 FILTER - OFF NOTE: SETTINGS LISTED WERE USED TO DEVELOP PROCEDURE. VALUES MAY VARY FROM INSTRUMENT TO INSTRUMENT LIFT-OFF SCOPE PRESENTATION AFT PRESSURE BULKHEAD TEE - INSPECTION March 28/90 FIGURE 3 (SHEET 17 OF 17) Bulletin A53-232 Revision 2 April 28/95 Page 43 McDonnell Douglas Corporation Proprietary Information. Use or ot œure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE ### Page 45 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN GENERAL NOTES: 1. FINAL SHAPE AND SIZE OF MODIFICATION TO BE DETERMINED BY THE OPERATOR AND TRIMMED ON ASSEMBLY. 2. SMOOTH AND BLEND OUT ALL EVIDENCE OF CORROSION, 63-MICROINCH FINISH. 3. 125-MICROINCH SURFACE FINISH TYPICAL. 4. BREAK ALL SHARP EDGES .020/.030-INCH RADIUS. 5. SHIM AS REQUIRED TO RELIEVE PRELOAD. 6. PROTECT MODIFICATION AREA AGAINST CORROSION AND DISSIMILAR METALS PER SRM CHAPTER 51-10-3. 7. APPLY A FAYING SURFACE SEAL OF PR-1422 B-2 SEALANT BETWEEN ALL DOUBLERS, BOLTS, HI-LOKS, AND RIVETS WET WITH SEALANT UNDER HEADS, BETWEEN WASHERS AND MATING SURFACES PER SRM CHAPTER 51-20-0. FILLERS, SPLICES, SHIMS, ANGLES, STIFFENERS, TEES, AND FITTINGS. INSTALL 8. LOCATE ATTACHMENTS FROM PART EDGES AS FOLLOWS: 2D + .06-INCH (1.5 M;) FOR DETAIL PARTS. 2D MINIMUM ACCEPTABLE ON ASSEMBLY. 9. ADDED ATTACHMENTS TO BE LOCATED 2D FROM JOGGLES. 10. "EQUAL SPACED" ATTACHMENT TOLERANCE TO BE WITHIN .06-INCH (1.5 MM). 11. OVERSIZE ATTACHMENT MUST BE USED WHEN THE EXISTING HOLE DIAMETER EXCEEDS THE MAXIMUM DIAMETER SPECIFIED FOR THE ATTACHMENT. 12. SEE TABLE III FOR REPLACEMENT FASTENERS. SEE SERVICE REWORK DRAWING HAS BEEN ACCOMPLISHED. SR09530083 FOR REPLACEMENT FASTENERS IF DC-9 SERVICE BULLETIN 53-147 13. IT IS PERMISSIBLE TO USE SELF-ALIGNING NUTS IN PLACE OF NAS679A OR MS21042L3 NUTS. 14. SPLICING OF TEE IS ACCEPTABLE TO FACILITATE INSTALLATION AND ASSEMBLY, SPLICE PER SERVICE REWORK DRAWING SRO9530001 AND/OR STRUCTURAL REPAIR MANUAL CHAPTERS 51-10 AND 53-03. 15. AT OPERATORS OPTION IT IS PERMISSIBLE TO CUT 5910163-73 ANGLE AND USE SRM CHAPTER 53-03 FIGURE 14 TO FABRICATE A MODIFICATION SPLICE IN ANGLE TO GAIN SPLICE PER SIDE IS PERMITTED. ACCESS IN RESTRICTED AREA ON FORWARD SIDE OF TEE SECTION. A MAXIMUM OF ONE TOLERANCES IN. = INCHES MM = MILLIMETERS ANGLES + 0° 30' 3 PLACE DECIMAL ‡ .015 IN. (0.38 MM) 2 PLACE DECIMAL ‡.03 IN. (0.8 MM) AFT PRESSURE BULKHEAD TEE - MODIFICATION Bulletin A53-232 FIGURE 4 (SHEET 1 OF 6) March 28/90 Page 44 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE ### Page 46 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN TABLE I QUANTITY PER VENTRAL BULKHEAD CONDITION DOUBLER CONFIGURATION WITH 9918572 DOUBLER WITHOUT 9918572 DOUBLER PART NO. KEY WORD QTY QTY HL325-5-4 PIN HL325-5-5 HL325-5-6 p HLT335-6-6 HLT335-6-7 'IN HLT41-5-5 PIN HLT41-5-6 PIN HLT434-6-6 PIN HLT435-6-4 PIN HLT435-6-6 PIN HLT436-6-5 PIN HLT436-6-6 PIN HLT436-6-7 PIN HLT634-6-6 PIN HLT634-6-7 PIN HLT635-6-5 PIN HLT635-6-6 PIN HLT635-6-7 PIN MS20470AD5-6 RIVET MS20470AD5-7 RIVET MS20470AD6-6 RIVET MS20470AD6-7 RIVET MS21042L3 NUT MAS1097AD5-9 RIVET NAS1097AD6-10 RIVET NAS1097AD6-9 RIVET 280 NAS1252-10L WASHER S2931983-30A06 WASHER S4931919-6-3 PIN S4931919-6-4 PIN S4931919-6-5 PIN 54931919-6-6 PIN S4931919-6-7 PIN S4931920-6-5 PIN S4931920-6-6 PIN S4931920-6-7 PIN SR09530056-3 TEE 5910163-389 SR09530056-5 TEE 5910163-391 SR09530056-6 TEE 5910163-392 SR09530056-7 TEE 1 5910163-393 SR09530056-8 TEE 1 5910163-394 SR09530056-9 TEE 1 1 5910163-387 3D0006-08 NOT ASSY 472 300006-3 NUT ASSY 1368 728 AFT PRESSURE BULKHEAD TEE - MODIFICATION March 28/90 FIGURE 4 (SHEET 2 OF 6) Bulletin A53-232 Revision 2 April 28/95 Page 45 McDonnell Dougles Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 47 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN STA Y= 817.000 (SERIES 10 and 20) Y= 996.000 (SERIES 30) Y=1072.000 (SERIES 40) =1167.000 SERIES 50) Y=1338.000 (MD-80) Y=1129.000 (MD-87) TABLE II VENTRAL AFT PRESSURE BULKHEAD MAY BE REPLACED WITH NEW IMPROVED GLASS OLD PART NO. SHOT PEENED PART NO. 5910130-51 OR SRO9530056-3 TEE 5919130-389 5910163-389 5910130-53 OR SR09530056-5 TEE OR 5910130-391 5910163-391 5910130-54 OR SR09530056-6 TEE OR 5910130-392 5910163-392 5910130-55 OR SRO9530056-7 TEE OR 5910130-393 5910163-393 5910130-56 OR SRO9530056-8 TEE OR 5910130-394 5910163-394 5910130-47 OR SRO9530056-9 TEE OR 5910130-387 5910163-387 AFT PRESSURE BULKHEAD TEE - MODIFICATION Bulletin A53-232 FIGURE 4 (SHEET 3 OF 6) March 28/90 Page 46 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 48 (OCR) •LER I DOUGLAS AIRCRAFT COMPANY ALERT. SERVICE BULLETIN FLUSH HEAD HI-LOK FASTENERS (TYP) - REPLACE ALL FASTENERS WITH HI-LOK OR RIVET FASTENERS (TYP) VIEW B-B REPLACE ALL FASTENERS WITH FLUSH HEAD FASTENERS (TYP) - SR09530056-3 OR 5910163-389 SR09530065-5 TEE 5910163-391 OR - SR09530056-6 OR TEE 5910163-392 TEE PRODUCTION SR09530056-7 SPLICE (TYP) OR 5910163-393 TEE FUSELAGE REFERENCE PLANE SR09530056-9 OR SR09530056-8 TEE 5910163-387 B 5910163-394 TEE OR VIEW A-A VIEW LOOKING FORWARD AT NON-VENTRAL AFT PRESSURE BULKHEAD AFT PRESSURE BULKHEAD TEE - MODIFICATION March 28/90 FIGURE 4 (SHEET 4 OF 6) Bulletin A53-232 Revision 2 April 28/95 Page 47 McDonnell Douglas Corporation Propristary Information. Use or diaclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 49 (OCR) ALERT DoUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN TABLE III REFERENCE CODE USED ON DRAWING FASTENER TO REPLACE WITH 5910130 BE REMOVED FASTENER HL326-5-X PIN, S4931920-6-X PIN, S4933653-3 NUT ASSY 3D0006-3 NUT ASSY IL329-5-X PIN S4931919-6-X PIN, 4933653-08 NUT ASS 3D0006-08 NUT ASSY HL328-5-X PIN, 54931920-6-X PIN, S4933653-08 NUT ASSI 3D0006-3 NUT ASSY BF 4_ MS20427M4 RIVET HLT41-5-X PIN, 3D0006-08 NUT ASSY BF S MS20427M5 RIVET 54931919-6-X PIN 300006-3 MUT ASSY MS20470AD5-X RIVET SAME, OR S4931920-6-X PIN, NAS1252-1OL WASHER, MS21042L3 NUT BJ}6 MS20470AD6-X RIVET SAME, OR HLT634-6-X PIN WASHER, S2931983-30A06 MS21042L3 NUT Cx/5 MS20470DD5-X RIVET 54931919-6-X PIN, 300006-3 NUT ASSY NAS1252-8L WASHER, HL328-5-X PIN, NAS1252-1OL WASHER, S4931920-6-X PIN, MS21042L08 NUT MS21042L3 NUT 54931920-6-X PIN, HLT334-6-X PIN, S4933653-3 NUT ASSY 3D0006-3 NUT ASSY LN A MS20615M4 RIVET HL325-5-X PIN, 3D0006-08 NUT ASSY AFT PRESSURE BULKHEAD TEE - MODIFICATION Bulletin A53-232 FIGURE 4 (SHEET 5 OF 6) March 28/90 Page 48 Revision 2 April 28/95 McDonnell Douglas Corporation Proprietary Information. Use or discloure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 50 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN - TABLE III (CONT) REFERENCE CODE USED ON DRAWING FASTENER TO REPLACE WITH 5910130 BE REMOVED FASTENER LN 5 MS20615-5M RIVET S4931919-6-X PIN, 3D0006-3 NUT ASSY LZ|5 NAS1097AD5-X RIVET SAME, OR NAS1097AD6-X RIVET LZ 6 NAS1097AD6-X RIVET SAME, OR HLT635-6-X PIN, 3D0006-3 NUT ASSY MC15 NAS1097DD5-X RIVET HLT335-6-X PIN, 3D0006-3 NUT ASSY S4579428-5-X RIVET S4931919-6-X PIN, 3D0006-3 NUT ASSY 9 мах S4579428-6-X RIVET HLT635-6-X PIN, 3D0006-3 NUT ASSY S4931920-6-X PIN, HLT436-6-X PIN, S4932389-3 NUT S2931983-30A06 WASHEF MS21042L3 NUT 4931919-6-X PIN, HLT635-6-X PIN, S4932389-3 NUT S2931983-30A06 WASHER MS21042L3 NUT 91 89х S4579428DD6 RIVET HLT635-6-X PIN, 3D0006-3 NUT ASSY XKF |6 S4931920-6-X PIN, HLT436-6-X PIN, 54933653-3 NUT ASSY 3D0006-3 NUT ASSY AFT PRESSURE BULKHEAD TEE - MODIFICATION March 28/90 FIGURE 4 (SHEET 6 OF 6) Bulletin A53-232 Revision 2 April 28/95 Page 49 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 51 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN GENERAL NOTES: THE PURPOSE OF THIS FIGURE IS TO PROVIDE SPECIFIC MINIMUM RECOMMENDED SHORING PROVISIONS FOR THE SPLICING IN OR REPLACEMENT OF A CRACKED 5910130/5930760 (FUSELAGE NUMBER 1071 AND SUBSEQUENT) TEE, VENTRAL AFT PRESSURE BULKHEAD, PER DAC SERVICE REWORK DRAWING SRO9530001 OR SRO9530056. 2. RAISE AND LEVEL AIRCRAFT AND SHORE AS SHOWN. REFER TO THE DC-9 MAINTENANCE MANUAL AND APPLICABLE LIFTING, LEVELING AND SHORING INSTRUCTIONS, CAUTIONS AND LIMITATIONS: (A) 7-11-0 "WING AND FUSELAGE LIFTING" (8] 7-20-0 "SHORING" (C) 8-10-0 "LEVELING" AIRCRAFT TO BE LEVEL WITHIN 2 DEGREES. 3. INSTALL CRADLE FOR AIRCRAFT WITH VENTRAL PRESSURE BULKHEAD. CAUTION: THE AFT FUSELAGE CRADLE RESTS AGAINST SLOPING FUSELAGE SKIN SURFACE. RESTRAIN AIRCRAFT AND CRADLE FROM SLIPPAGE IF REQUIRED. 4. JACK AT AFT FUS JACK POINT SHALL BE REMOVED DURING MODIFICATION OR REPAIR OF AFT PRESSURE BULKHEAD. 5. USE -1 SHORING CONFIGURATION ONLY FOR SIDE TEE REPLACEMENT BETWEEN LONGERON 6.5 TO LONGERON 22.5 (LEFT AND RIGHT SIDES), PART NUMBERS 5910130-53, -54, -55 OR -56. DO NOT REPLACE LEFT AND RIGHT SIDES TEES AT SAME TIME. 6. ADD -501 SHORING CONFIGURATION FOR UPPER TEE REPLACEMENT BETWEEN LONGERON 6.5 (LEFT SIDE) AND LONGERON 6.5-(RIGHT SIDE), PART NUMBER 5910130-51. FOR LOWER TEE REPLACEMENT BETWEEN LONGERON.22.5 (LEFT SIDE) AND LONGERON ALSO 22.5 (RIGHT SIDE), PART NUMBER 5910130-47. 7. REMOVE TAILCONE PER MAINTENANCE MANUAL 53-50-3. 8. INSTALL DAC SERVICE REWORK DRAWING J060157 SHORING PROVISIONS ON AFT CANTED FRAME. 9. AFTER INSTALLING SUPPORT AT AFT CANTED FRAME, ACCOMPLISH THE FOLLOWING: a. APPLY 50 + 25 POUND FORCE PRELOAD TO PROVIDE POSITIVE UP LOAD ON JACK. D. MEASURE GAP BETWEEN SKINS PRIOR TO REMOVAL OF ANY ATTACHMENTS (TYPICALLY .010 TO .120). C. AFTER START OF ATTACHMENT REMOVAL, CHECK GAP AND POSSIBLE HOLE MISALIGNMENT. APPLY LOAD TO JACK AS REQUIRED TO MAINTAIN GAP BETWEEN SKINS NOTED PREVIOUSLY. SHORING INSTRUCTIONS - VENTRAL AFT PRESSURE BULKHEAD TEE REPLACEMENT Bulletin A53-232 FIGURE 5 (SHEET 1 OF 3) March 28/90 Page 50 Revision 2 April 28/95 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 52 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN CAUTION: INSTALL CRADLES ONLY AFTER AIRCRAFT IS LEVEL AND ON WING AND AFT FUSELAGE JACKS. REMOVE CRADLES BEFORE RELEASING WING AND AFT FUSELAGE JACKS. SEVERE STRUCTURAL DAMAGE WILL OCCUR IF WING JACKS ARE RELEASED WHEN CRADLE AND JACK AT AFT FUSELAGE JACK POINTS ARE INSTALLED. - WING JACK AT STA Xrs=111.875 (ALL SERIES EXCEPT MD-80) STA XCW=121.688 (MD-80) (LS AND RS) INSTALL CRADLE AT STA Y=110.000 (SEE CAUTION) -501 (SEE SHEET 3) REMOVE BOTH ENGINES CRADLE AT STA Y=718.000 MANUAL CHAPTER 71-00-0) (REF: MAINTENANCE (SERIES 10 AND 20) STA Y=897.000 (SERIES 30) AFT FUS JACK POINT STA Y=973.000 VENTRAL A/C ONLY CRADLE AT (SERIES 40) AFT PRESSURE BULKHEAD STA Y=859.868 STA Y=1068.000 (SERIES 50) STA Y=817.000 (SERIES 10 AND 20) (SERIES 10 AND 20) STA Y=1038.868 STA Y=1239.000 STA Y=996.000 (SERIES 30) STA Y=1030.000 (1D-87) (MD-80) (SERIES 40) (SERIES 30) STA Y=1072.000 STA Y=1209.868 (SERIES 40) STA Y=1114.868 (SEE CAUTION) STA Y=1167.000 (SERIES 50) (SERIES 50) STA Y=1380.868 STA Y=1338.000 (MD-80) (MD-80) STA Y=1171.868 STA Y=1129.000 (MD-87) (MD-87) SEE GENERAL NOTE 3 SEE GENERAL NOTE 4 -1 SHORING CONFIGURATION SHORING INSTRUCTIONS - VENTRAL AFT PRESSURE BULKHEAD TEE REPLACEMENT March 28/90 FIGURE 5 (SHEET 2 OF 3) Bulletin A53-232 Revision 2 April 28/95 Page 51 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITI E PAGE nD ODOT DAF ### Page 53 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN 5910130 VENTRAL AFT PRESSURE BULKHEAD TEE SHORING •- FRP PROVISIONS P/N J060157-1 STA Y=989.407 (SERIES 10 AND 20) STA Y=1168.407 STA Y=916.000 (SERIES 30) P/N 2958 STA Y=817.000 (SERIES 10 AND 20) STA Y=1244.407 JACK (REF) STA Y=996.000 (SERIES 10 AND 20) (SERIES 30) STA Y=1095.000 (SERIES 40) STA Y=1339.407 (SERIES 30) STA Y=1072.000 (SERIES 40) STA Y=1171.000 (SERIES 50) STA Y=1510.407 (SERIES 40) (SERTES 50,000 (MD-80) STA Y=1167.000 (SERIES STA Y=1301.407 (SERIES 50) STA Y=1437.000 (MD-87) (MD-80) STA Y=1338.000 STA Y=1228.000 (MD-80) STA Y=1129.000 (HD-87) (MD-87) -501 SHORING CONFIGURATION SHORING INSTRUCTIONS - VENTRAL AFT PRESSURE BULKHEAD TEE REPLACEMENT Bulletin A53-232 FIGURE 5 (SHEET 3 OF 3) March 28/90 Page 52 Revision 2 April 28/95 McDonnell Douglas Corporation Propristary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 54 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN 3. Material Information: A. The basis for the following material data is per aircraft. (1) Parts to be purchased as end item spares. NOTE: Parts requirements are contingent upon inspection findings indicating the existence of crack(s) in a tee section. Maximum quantities required per Figure 4, Table 1, are listed. Actual parts requirements are to be determined by the operator. Quantities listed are for record purposes only. Parts within parentheses are production equivalent part numbers. Part No. Qty Key Hord SR09530056-3 1 Tee (5910163-389) SR09530056-5 Tee (5910163-391) SR09530056-6 Tee (5910163-392) SR09530056-7 Tee (5910163-393) SR09530056-8 Tee (5910163-394) SRO9530056-9 1 Tee (5910163-387) S2931983-30A06 297 Washer S4931919-6-3 12 Pin S4931919-6-4 4 Pin S4931919-6-5 315 Pin S4931919-6-6 300 Pin S4931919-6-7 30 Pin 54931920-6-5 55 Pin S4931920-6-6 73 Pin S4931920-6-7 18 pin 3D0006-08 472 Hut Assembly 3D0006-3 1368 Nut Assembly (2) Fastener kit consists of the following parts and may be purchased from DAC or may be procured from operator's stock or source indicated. Maximum quantities are listed, actual fasteners required are contingent upon inspection findings and are to be determined by the operator. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 53 McDonneli Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 55 (OCR) ALERT DouGLAS AIRcRaFT cOMPANY ALERT SERVICE BULLETIN Qty Kit Part/Material SB09530232-3 CAGE Supplier HLT335-6-6 Pin 20 73197 Hi-Shear Corporation HLT335-6-7 Pin 10 2600 Skypark Drive HLT41-5-5 Pin 234 Torrance, California HLT41-5-6 Pin 234 90506 HLT434-6-6 Pin 20 HLT435-6-4 Pin 5 HLT435-6-6 Pin 18 HLT436-6-5 Pin 15 HLT436-6-6 Pin 72 HLT436-6-7 Pin 72 HLT634-6-6 Pin 120 HLT634-6-7 Pin 120 HLT635-6-5 Pin 237 HLT635-6-6 Pin 275 HLT635-6-7 Pin 72 HL325-5-4 Pin HL325-5-5 Pin 131 HL325-5-6 Pin 132 MS20470AD5-6 Rivet 214 MS20470AD5-7 Rivet 267 MS20470AD6-6 Rivet 123 MS20470AD6-7 Rivet 114 MS21042L3 Nut 551 NAS1097AD5-9 Rivet 50 NAS1097AD6-10 Rivet 10 NAS1097AD6-9 Rivet 375 NAS1252-10L Washer 275_. (3) Material to be procured from operator's stock or source indicated. Part/Material Qty CAGE Supplier PR-1422 B-2 Sealant 1 Qt 83574 Courtaulds Aerospace (DMS 2082) 5430 San Fernando Road or Glendale, California Equivalent 91209 B. The basis for the following material data is per spares. None. Bulletin A53-232 March 28/90 Page 54 Revision 2 April 28/95 McDonnell Dougles Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 56 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN C. The basis for the following tooling data is per operator. (1) Option I - Test equipment to be procured from operator's stock or sources indicated. NOTE: One 70 or 90 degree endoscope of any diameter with 18-inch (457.2 MM) minimum length and matching light source may be used. Test Equipment Type DEY CAGE Supplier Endoscope 70 Degree Model 54341 Expanded Optics, (Fore oblique) Angle 10320D Incorporated 19-Inch (482.6 MM) Long 7382 Bolsa Avenue 0.217-Inch Diameter Westminster, California 92683 Equivalent Fiber Optic Model Light Bundle 1F8D3 and Endoscope Light Source NO. 00482 110 or 220 Volt or No. E0590 and Sylvania Projector Lamp 1 150 Watt, 120 Volt NOTE: Similar or equivalent endoscopes and illuminators may be obtained from the following sources. Alva Ingenieros Velazquez 121 Madrid 6, Spain or Automation Instruments Service 47 Birch Street Bankston 2200, Australia or March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 55 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 57 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Test Equipment Type DEY CAGE Supplier 3 G Electronics Sede Commercial 20135 Milano Via Perugino 9, Italy or 50958 Richard Wolf Medical Instrument Corporation 7046 Lyndon Avenue Rosemont, Illinois 60018-3410 or Inspection Instruments NDT Limited 10-12 Emerald Street London WC1, England Karl Storz KG D 7200 Tuttlingen West Germany Flexible Borescope Model 32212 Olympus Corporation 29.8-Inch (757 MM) Long 1F8D3 Scientific Products Group 0.315-Inch 2 Nevada Drive Diameter New Hyde Park, New York Cold Light Supply NO. ILK-4 1 100 to 230 Volt or Equivalent Eddy Current Flaw NDT-18 29192 Staveley Instruments Detector with or Incorporated Impedance Plane NDT-19 421 North Quay Street Display Kennewick, washington or 99336-7735 Zetec Eddy Current MIZ-20A 51327 Zetec Incorporated Instrument 1320 North West Mall or P.O. Box 140 Equivalent Issaquah, Washington 98027-8921 Eddy Current Low Model (Zetec Incorporated) Frequency Molded C/N 935-0120 Probe 5-50 kHz P/N APB/MSP Operating Frequency or Bulletin A53-232 March 28/90 Page 56 Revision 2 April 28/95 McDonnel Dougles Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 58 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT - SERVICE BULLETIN Test Equipment Type Oty CAGE Supplier Eddy Current Low Model (Staveley Instruments Frequency Molded SPO-4080 Incorporated) Probe 5-50 kHz Operating Frequency or Eddy Current Low Model (Staveley Instruments Frequency Molded SPO-5222 Incorporated) Probe 5-50 kHz Operating Frequency (To be used after Service Bulletin 53-147 has been accomplished.) Eddy Current Low Model (Zetec Incorporated) Frequency 90 Degree C/N 910-5830 Probe 5-50 kHz P/N APB/90DP Operating Frequency or Eddy Current Low Model (Staveley Instruments Frequency 90 Degree SPO-4081 Incorporated) Probe 5-50 KHz Operating Frequency NOTE: When ordering eddy current probes specify type of eddy current instrument the probe will be used with so that proper mating connectors or adapter will be provided. (2) Option I - One SB09530231-9 eddy current reference standard required to accomplish Option I low frequency eddy current inspection will be made available at no charge. (See paragraph 1.H.) (3) Option II - Test equipment required to accomplish Option II high and low frequency eddy current inspections including procurement sources, is listed in service sketch 3683D. Choice of equipment is at operator's option and is to be procured from operator's stock or sources indicated in service sketch 3683D. March 28/90 Bulletin A53-232 Revision 2 April 28/95 Page 57 McDonnell Douglas Corporation Propriatary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. ### Page 59 (OCR) ALERT DOUGLAS AIRCRAFT COMPANY ALERT SERVICE BULLETIN Option II - The following reference standard required to accomplish the Option II high and low frequency eddy current inspections is to be procured from operator's stock or as indicated. Instructions- Part No. Qty Key Nora Disposition MS20470AD5-6 2 Rivet MS20470AD5-7 4 Rivet SB09530231-11 1 Plate SB09530231-13 1 Web SB09530231-15 Tee SB09530231-17 Reference Standard Assy 1/ May be purchased from: VM Products Incorporated CAGE 11298 62nd Avenue 60761 Puyallup, Washington 98373 or May be fabricated by the operator. (See service sketch 3683C.) 2/ May be procured from operator's stock. 3/ Detail of SB09530231-17 reference standard assembly. 4/ May be fabricated by the operator from 7075-T6 clad aluminum sheet Material Specification QQ-A-250/13 Temper T6 or 7075-T6 bare aluminum plate Material Specification QQ-A-250/12 Temper T6, .047/.053 × 2-1/4 x 3 inches. (See service sketch 3683D.) 2/ May be fabricated by the operator from 7075-T6 clad aluminum sheet Material Specification 0Q-A-250/13 Temper T6 or 7075-T6 bare aluminum plate Material Specification QQ-A-250/12 Temper T6, .039/.045 × 2-1/4 × 4-1/2 inches. (See service sketch 3683D.) 6/ May be fabricated by the operator from 2024-T3 clad aluminum sheet Material Specification QQ-A-250/5 Temper T3 or 2024-T4 bare aluminum plate Material Specification QQ-A-250/4 Temper T4, .075/.085 x 3 x 4-112 inches. (See service sketch 3683C.) any inquiries regarding accuracy, timeliness, completeness, anc legibility of this Service Bulletin should be directed to the local DAC Field Representative, or: Douglas Aircraft Company P.O. Box 1771 Long Beach, Calitornia 9080l Attn: Business Unit Manager Service Bulletins Maintenance and Modification Engineering Product Support 35-35 (DC-9 Alert Service Bulletin A53-232) ENW/CAS/ENW LL/AMM Bulletin A53-232 March 28/90 Page 58 Revision 2 April 28/95 McDonnel Douglas Corporation Proprietary Information. Lee or daciosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE. --- 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.