McDonnell Douglas SB A53-231: Revision 2

DOUGLAS AIRCRAFT COMPANY ALERT

MCDONNELL DOUGLAS OC-S BULLETIN A53-231 ¡SERVICE BULLETIN;

REVISION TRANSMITTAL SHEET FUSELAGE - Main Frame - Inspect/Repair Aft Fuselage Non-Ventral Pressure Bulkhead Tee.

This page transmits Revision 2 for DC-9 Alert Service Bulletin A53-231 to incorporate the following changes:

NOTE: This revision constitutes a complete reissue and reflects current operators of affected aircraft at time of issue.

Reason for Revision: To incorporate engineering released subsequent to prior issue of this Alert Service Bulletin, which adds a different eddy current probe for aircraft which have accomplished Alert Service Bulletin A53-147. A different eddy current probe is required because an operator could not inspect aft pressure bulkhead tee using the standard probe provided by prior issue of this Service Bulletin.

This condition is due to the length of Hi-Lok pins used to modify aircraft per DC-9 Service Bulletin A53-147.

No additional work is required by this revision for aircraft previously inspected/repaired by prior issue of this Alert Service Bulletin.

Page 1: Changed page number to I of 50, was I of 46.

Pages 6 Added NOTE under paragraph 1.C., Option II, Condition 2.

and 7:

Revised Approval statement.

Pages 10 Changed Service Sketch to 3683D, was 3683C.

and 11: Added DC-9 Service Bulletin A53-147 to References as new paragraph

1.J. (2). Reidentified subsequent paragraphs accordingly.

Added paragraphs I.L and 1.M.

Pages 12 Added new GENERAL NOTE 1, reidentified subsequent notes accordingly.

14, and 15: Added new paragraph 2.C, reidentified subsequent paragraphs accordingly.

Added NOTE under paragraphs 2.A. (4) and 2.K. (4).

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.

Bulletin A53-231 February 24/89 Page 1 of 2 Revision 2 June 25/93

ALERT DOUGLAS AIRCRAFT COMPANY ALERT* Pages 19 Revised Figure 3 as follows:

thru 35:

Added NOTE under paragraph 8.f.(1) on Sheet 2 of 17.

Added Note under paragraph B. (1)(a) and revised paragraph

(1)(c) under Sequence 1 on Sheet 4 of 17.

Revised paragraph (1)(c) under Sequence 2 on Sheet 5 of 17.

Added new sheet 7, and 15 through 17. Reidentified sheets accordingly.

Revised callout for eddy current probe on Sheet 6 of 17.

Revised callout for eddy current probe on Sheet 8 of 17.

Pages 45 Revised paragraphs 3.A(1) and 3.A.(3).

and 46:

Pages 47 Revised paragraphs 3.C. (1) and 3.C.(4).

and 50:

Revision Sequence:

Original Date February 24/89 Revision l April 2/90 Revision 2 June 25/93 CAS LL-2 Bulletin A53-231 February 24/89 Page 2 Revision 2 June 25/93 McDonnell Dougles Corporation Proprietary Inforation. Ues or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

DOUGLAS AIRCRAFT COMPANY ALERT

MCDONNELL DOUGLAS DC-S PO 80x 1771 Long Beach, CA BULLETIN A53-231 90801

SERVICE BULLETIN FUSELAGE - Main Frame - Inspect/Repair Aft Fuselage Non-Ventral Pressure Bulkhead Tee.

NOTE This Alert Service Bulletin is affected by Federal Aviation Administration Airworthiness Directive No.

89-06-04: Amendment 39-6152, effective March 24, 1989.

This Alert Service Bulletin is applicable only to aircraft equipped with the non-ventral aft pressure bulkhead which have accumulated 25,000 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.

I. Planning Information:

A. Effectivity:

(1) Aircraft Affected:

2c-2. Series 10. 30. and c-9 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.

February 24/89 Bulletin A53-231 | Revision 2 June 25/93 Page 1 of 50

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN

(a) Operator and Aircraft Number:

Operator Factory Serial No. Operator Factory Serial No.

45845 GB 45728 47019 45874 47021 and 47022 47040 47024 47074 47069 thru 47071 47147 and 47148 47195 47165 47198 and 47199 47269 47265 and 47266 47384 47289 and 47290 47403 47292 thru 47294 47413 47340 thru 47342 47348 thru 47350 TI 47408 47353 and 47354 47422 JP 47392 47485 47546 ML and 47554 45838 thru 47557 and 47560 47592 47598 47611 47166 and 47167 BD . 45712 and 45713 47186 and 47187 45719 47214 45738 and 45739 47048 NK 47268 47423 and 47424 NW nayz pur 45708 EA 45733 and 45734 45833 and 45834 FALSE 45837 OLLSE 45863 thru 45865 45825 47161 6289₺ thru 45832 47181 47049 47215 47097 47327 and 47328 47139 47402 47141 thru 47145 47158 EZ 47220 47355 47162 47182 and thru 47164 47183 47414 47185 47376 FP 45702 Bulletin A53-231 February 24/89 Page 2 Revision 2 June 25/93 McDonnell Dougles Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN Operator Factory Serial No. Operator Factory Serial No.

RS 45721 and 45722 ZCP 47151 45776 45780 and 45781 ZDF 45871 thru 45873 45783 47270 and 47271 47125 47127 ZGM 45778 45782 TW 47082 45784 47095 and 47096 47134 thru 47137 ZG4 47329 47409 ZIL 45698 and 45699 US 45846 47060 45868 47020 ZJ6 45775 47023 47053 and 47054 ZK7 45740 47057 and 47058 47066 ZNV 47041 47068 47221 47188 and 47189 47639 47216 47351 and 47352 Z3Z 45701 45709 VC 45875 45723 47036 47272 Z4B 45695 47330 and 47331 47399 Z5F 47123 47401 47119 XYX 45696 45711 Z5Y 45715 and 45716 45718 45735 45725 45737 45727 45741 and 45742 45795 45842 45843 45779 and 45844 YUZ 45720 Z6H 47217 ZCA 45714 Z7B 45730 45736 45743 Z8H 45706 47043 47059 47085 47122 47126 Bulletin A53-231 February 24/89 Page 3 Revision 2 June 25/93 McDonnell Douglas Corporation Proprietary Information. Les or disclosure of

THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN

(b) Manufacturer's Fuselage and Factory Serial Numbers:

EUS (ESN) FUS (ESN) EUS (FSN) EUS (ES12 EUS (ESN EUS (ESN) 10 (45715) 12(45701) 21 (45703) 23 (45842) 13 (45716) 14 (45728) 24 (45704) 27 (45720) 15 (45702) 16(45729) 17 (45718) 18(45719) 19(45725) 25(45735) 26 (45742) 28 (45843) 35(47048) 38(45746) 29 (45743) 37 (45730) 31(45744) 32(45745) 33 (45844) 45 (45736) 103 (45837) 200 (47041) 303 (47189) 406 (47329) 43 (45727) 44 (45721) 40(45747) 42 (47049) 9(45713) 1(45695) 2(45696) 5(45698) 6(45712) 7 (45714) 8 (45699) 4(45711) 101 (45781) 49 (45737) 57 (45770) 50 (45749) 56(45739) 47(45748) 48 (45733) 53(45705) 54(45738) 55(45722) 62 (45740) 60 (45734) 61(45706) 63 (45723) 65 (45795) 66 (45741) 67 (45825) 70(45707) 72 (45776) 68 (45829) 71(45775) 73 (45833) 75(45830) 76(45831) 77 (45708) 78 (45709) 88 (47043) 92 (45779) 82 (45778) 91(45845) 93 (45780) 96(45836) 84(45832) 85 (45834) 95(45835) 109 (47060) 112(45846) 107 (47053) 110 (47054) 113(47019) 104 (45838) 122 (47057) 128 (45783) 126 (47020) 114(45782) 116(45839) 117(45840) 123(47058) 124 (45863) 125(47059) 130 (45864) 137 (45865) 133 (47021) 138 139 140 144 160 (47068) 150 158 159 181 (47082) 175 (47069) 188(47071) 191(47095) 192(47096) 193 (47097) 169 (47139) 172 (47040) 176 (47070) (47085) (47024) (47066) (47022) (45866) (45784) (47023) 215(47134) 208 212(47140) 246(47148) 239(47144) 224 (47122) 227 232 (47142) 233(47135) 238 (47143) 243 (47136) 247 (47145) 248(47158) 249(47161) 253 (47123) 255(47162) 256(47163) 259 258 260 265 266 267 271 272 275 276 278 282 283 285 291 (47188) 296 (47220) 302 (47198) 290 (47147) (47141) (47137) (47187) (47164) (47167) (47185) (47165) (47166) (47182) (47181) (47195) (47183) (47186) (47151) (45868) (45867) 305 (47221) 306(47214) 313(47215) 315 321 360 (47217) 345 (45872) 350 (45873) 351 (45874) 322 331 339 (47265) 344 (45871) 353 (47289) 365 366 367 370 376 (47074) 383 (47292) 352 371 374 375 378 (47119) 389 (47271) 390 (47272) 391 (47327) 403 (47340) 384 (47293) 388 392 402 (47294) 404 (47341) 405 (47126) (47216) (47157) (45869) (47266) (47199) (47036) (45875) (45876) (47290) (47268) (47269) (47270) (47125) (47328) 430 (47399) 408 (47331) 417 (47127) 407 (47330) 418 419 420 431 (47350) 442 447 (47392) 467(47408) 471 (47353) 517 (47376) 521 (47413) 452 (47355) 543 (47384) 576 (47422) 444 (47401) 453 482 (47402) 483 497 (47409) 507 (47403) 536 (47414) 581 (47423) 658 (47554) 582 (47424) 655 (47546) 666 (47485) 712 (47592) 719(47598) 726(47611) 661 (47557) 735 (47639) 664 (47560) . (47351) (47342) (47348) (47352) (47349) (47354) This modification is applicable only to listed aircraft.

(2) Spares Affected:

None.

February 24/89 Bulletin A53-231 Revision 2 June 25/93 Page 4 McDonnell Douglas Corporation Propriatary Information. Use or discioure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN B. Reason:

One operator reported a cracked aft pressure bulkhead attach tee section on one afrcraft. The aircraft was a non-ventral bulkhead aircraft. The crack in the upstanding leg of the tee extended circumferentially approximately 24 inches from the production end of the tee, at splice between longerons 17 and 18 left side, upward to longeron 15. The affected aircraft had accumulated 36,079 landings when the crack was found. Analysis of the failed part revealed that the crack 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. Five other operators reported cracks in a total of 39,172 and 81,915 landings. The predominant areas of cracks were at eight other aircraft. These eight aircraft had accumulated between the upper splice between longeron 6 and 7 (4 cases left side); one crack occurred respectively at longeron 8, 11, 12, 13, and 15 (predominately on left side); and lower pylon attach angle at or between longeron 16 and 17(5 cases left side and one case right side). 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.

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 the entire periphery of the fuselage from the aft side of the bulkhead and accomplishes the following:

Condition (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.

February 24/89 Bulletin A53-231 Revision 2 June 25/93 Page 5 McDonnell Douglas Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN Option Il (Inspection from forward side of oulkhead) 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 repetitively high and low frequency eddy current inspects for cracks from forward side of bulkhead at intervals specified in Compliance paragraph.

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.

D. Comp lance:

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 25,000 landings.

Accumulated Landings Initial Inspection 25,000 to 49,999 Within 1500 landings from issue date of Revision 1 of this Service Bulletin 50,000 to 59,999 Within 1000 landings from issue date of Revision l of this Service Bulletin 60,000 and over Within 300 landings from issue date of Revision l 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 25,000 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.

Bulletin A53-231 February 24/89 Page 6 Revision 2 June 25/93 McDonnell Dougles Corporation Propristary Information. Lee or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

• ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN When aft pressure bulkhead tee section is replaced with new improved part per this Alert 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 L7 and L17 on fuselage left and right sides, be accomplished at intervals not to exceed 2000 landings.

It is recommended that repetitive visual inspection for cracks of top and lower areas from longeron L7 left side to longeron L7 right side, and lower fuselage longeron L17 to longeron L20 on fuselage left and right sides, be accomplished at intervals not to exceed 1500 landings.

It is recommended that repetitive visual inspection for cracks of bottom areas from longeron L20 left side to L20 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 1s approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region on June 17, 1993, and is approved as an alternate means of compliance with paragraphs A, B, and C of Airworthiness Directive No. 89-06-04.

February 24/89 Bulletin A53-231 Revision 2 June 25/93 Page 7 McDonnell Douglas Corporation Propristary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN F. Manpower:

Man-hours are estimated based on work to be performed by skilled personnel on aircraft/unit which has been placed in a maintenance status. The man-hour/elapsed time estimates do not include:

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.

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 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.

Bulletin A53-231 February 24/89 Revision 2 June 25/93 Page 8 McDonnell Dougles Corporation Propristary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN G. Material - Cost and Availability:

(1) Aircrait:

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 78-22 (DC-9 Alert Service Bulletin A53-231)

(2) Spares:

Not applicable.

H. Iooling - Price and Availability:

Option I (Inspection from aft side of bulkhead) 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.

Douglas special 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 SB08530231-9 special eddy current Douglas Aircraft Company. Specify this Service Bulletin number and reference standard should be negotiated between the operator and the ire inquiries company.

Douglas Aircraft Company 910 East 236th Street Carson, California 92805 Group Leader - Recovery and Modification Services 78-22 (DC-9 Alert Service Bulletin A53-231) Bulletin A53-231 February 24/89 Page 9 Revision 2 June 25/93 McDonnell Dougles Corporation Proprietary Information. Use or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.

ALERT DOUGLAS AIRCRAFT COMPANY ALERT

SERVICE BULLETIN 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 36830.

(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 Alert 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.

J. References:

Federal Aviation Administration Airworthiness Directive No. 89-06-04: Amendment 39-6152, effective March 24, 1989.

(2) Alert Service Bulletin A53-147.

(3) Data used in preparation of this Alert Service Bulletin:

Data Identification Change Iype of Data J060157 DMS 2082 Douglas Material Specification Service Rework Shoring J060157 MM Chapters 6, 20. Advance E.O. Maintenance Manual 21, 25, 26, 36, SRM Chapters 51 and 53 NDT Chapter 1-3 SR09530001 SR09530001 SR09530048 SR09530056 49, 52, and 53 New C D Nondestructive Testing Manual Advance E.O. Structural Repair Manual Service Rework Drawing Service Rework Drawing Service Rework Drawing SR09530056 SR09530083 New D Advance E.O. Service Rework Drawing 5910163 5910163 DG, DH, DF Drawing Advance E.O.

and DJ 36830 Service Sketch (attached) February 24/89 Bulletin A53-231 Revision 2 June 25/93 Page 10 McDonnell Douglas Corporation Proprietary Information. Uss or disclosure of THESE DATA SUBJECT TO RESTRICTIVE LEGEND ON TITLE PAGE OR FIRST PAGE.