Boeing ASB 737-53A1279: Revision 2, text

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Commercial Airplanes 737 Service Bulletin ALERT Number: 737-53A1279 Original Issue: December 18, 2007 Revision 2: April 21, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Frames and Bulkheads - Forward Cargo Bay Stringer 19 to Stringer 22

- Frames and Frame Reinforcements - Inspection, Repair and Preventative Modification at Wire Penetration Hole, 0.50 Inch Diameter Hole, Standoff/Tooling Holes and Production Fastener Holes Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws.

9E991ECCN:

Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company.

Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 1 of 199

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Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 2 of 199 BOEING SERVICE BULLETIN 737-53A1279

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Table of Contents

Revision Transmittal Sheet5

Summary9

1. PLANNING INFORMATION15

A. Effectivity15

1. Airplanes15

2. Spares Affected26

B. Concurrent Requirements26

C. Reason26

D. Description28

E. Compliance30

F. Approval36

G. Manpower36

H. Weight and Balance Changes39

I. Electrical Load Data39

J. References39

1. Existing Data:39

2. Data Supplied with this Service Bulletin:40

3. Installation Drawings Used in the Preparation of this Service Bulletin:40

K. Publications Affected40

L. Interchangeability and Intermixability of Parts41

M. Software Accomplishment Summary41

2. MATERIAL INFORMATION43

A. Material - Price and Availability43

B. Industry Support Information43

C. Parts Necessary for Each Airplane43

1. Kits/Parts:43

2. Parts and Materials Supplied by the Operator:43

3. Parts Modified and Reidentified:43

4. Parts Removed and Not Replaced:43

D. Parts Necessary to Change Spares43

E. Special Tooling - Price and Availability43

F. Special Tooling Necessary to do this Service Bulletin44

3. ACCOMPLISHMENT INSTRUCTIONS45

A. GENERAL INFORMATION45

B. WORK INSTRUCTIONS46

FIGURE 1: FORWARD CARGO BAY - STATION 500A TO STATION 500D - WIRE SHROUD - REMOVAL

[Group 1, 4]58

FIGURE 2: FORWARD CARGO BAY - STATION 460 TO STATION 482B - WIRE SHROUD - REMOVAL

[Group 3, 6]62

FIGURE 3: FORWARD CARGO BAY - AFT BULKHEAD PANELS - REMOVAL66

FIGURE 4: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - MOVE [Group 1,

4]68

FIGURE 5: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - MOVE [Group 2,

5]73

FIGURE 6: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - MOVE [Group 3,

6]78

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 3 of 199 BOEING SERVICE BULLETIN 737-53A1279

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FIGURE 7: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) SURFACE INSPECTION [Group 1, 4]83

FIGURE 8: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) SURFACE INSPECTION [Group 2, 5]90

FIGURE 9: FORWARD CARGO BAY - STATION 482 TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) SURFACE INSPECTION [Group 3, 6]97

FIGURE 10: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 1, 4]104

FIGURE 11: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 2, 5]112

FIGURE 12: FORWARD CARGO BAY - STATION 482 TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 3, 6]120

FIGURE 13: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 1, 4]128

FIGURE 14: FORWARD CARGO BAY - STATION 500B TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 2, 5]136

FIGURE 15: FORWARD CARGO BAY - STATION 482 TO 520 FRAMES - HIGH FREQUENCY EDDY

CURRENT (HFEC) HOLE/EDGE INSPECTION [Group 3, 6]144

FIGURE 16: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - INSTALL [Group

1, 4]152

FIGURE 17: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - INSTALL [Group

2, 5]157

FIGURE 18: FORWARD CARGO BAY - POWER FEEDER CABLE GUIDE ASSEMBLY - INSTALL [Group

3, 6]162

FIGURE 19: FORWARD CARGO BAY - AFT BULKHEAD PANELS - INSTALL167

FIGURE 20: FORWARD CARGO BAY - STATION 500A TO STATION 500D - WIRE SHROUD - INSTALL

[Group 1, 4]169

FIGURE 21: FORWARD CARGO BAY - STATION 460 TO STATION 482B - WIRE SHROUD - INSTALL

[Group 3, 6]173

FIGURE 22: FORWARD CARGO BAY - STA 500B TO 520 FRAMES - DETAILED INSPECTION [Group 1,

4]177

FIGURE 23: FORWARD CARGO BAY - STA 500B TO 520 FRAMES - DETAILED INSPECTION [Group 2,

5]182

FIGURE 24: FORWARD CARGO BAY - STA 482 TO 520 FRAMES - DETAILED INSPECTION [Group 3, 6]

.187

FIGURE 25: FORWARD CARGO BAY - PREVENTATIVE MODIFICATION INSPECTION [Group 1-3,

Configuration 1]192

FIGURE 26: FORWARD CARGO BAY - PREVENTATIVE MODIFICATION INSPECTION [Group 4-6,

Configuration 1]196

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 4 of 199 BOEING SERVICE BULLETIN 737-53A1279

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Commercial Airplanes 737 Service Bulletin ALERT Revision Transmittal SheetNumber: 737-53A1279Original Issue: December 18, 2007 Revision 2: April 21, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Frames and Bulkheads - Forward Cargo Bay Stringer 19 to Stringer 22

COMPLIANCE INFORMATION RELATED TO THIS REVISION Federal Aviation Administration (FAA) Airworthiness Directive AD 2011-23-05 is related to this service bulletin.

AD 2011-23-05 supersedes AD 2009-02-06 R1.

The Federal Aviation Administration (FAA) will possibly release an additional Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory.

More work is necessary on airplanes changed or inspected in accordance with the Revision 1 or the original issue of this service bulletin:

ActionConditionGroup Accomplish post modification/repair inspection at compliance times in accordance with Paragraph 1.E., Compliance.

Previously accomplished the repair or preventative modification in accordance with Revision 1 or the original issue of this bulletin.

All Configurations 1 and 2.

Accomplish preventative modification before the threshold in accordance with Paragraph 1.E. Compliance.

Locations without a preventative modification or repair installed.

All Configurations 3.

NOTE: Part 26 DTI requirements provided in Revision 2 of this service bulletin supersede the DTI requirements for the previous revisions of this service bulletin contained in 737-300 SRM 53-00-07, 737-400 SRM 53-00-07, 737-500 SRM 53-00-07, Repair 13.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 5 of 199

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REASON FOR REVISION This revision is sent to add new inspection areas and to make sure of the accomplishment of inspections before the installation of preventative modifications installed between the dates March 12, 2012 and February 1, 2014.

This revision is also sent to add post preventative modification and repair inspections, and to add a compliance threshold for the accomplishment of the preventative modification. This revision also moves 737-300/-400 and -500 airplanes, line numbers 2566 thru 3132 into three new groups to separate bonded skin airplanes from solid skin airplanes.

These sections were changed:

1. Revised title to include new inspection, repair and preventative modification locations.

2. Summary – Background - Revised to include new inspection areas and Summary Evaluation Table is added.

– Action - New inspection areas are added.

– Compliance - Existing AD replaced by superseding AD and new more work table added.

– Graphic revised to show new inspection areas.

3. Paragraph 1.A1. Airplanes – Airplanes 737-300, line numbers 2566 thru 3132 are moved from group 1 to new group 4.

– Airplanes 737-400, line numbers 2566 thru 3132 are moved from group 2 to new group 5.

– Airplanes 737-500, line numbers 2566 thru 3132 are moved from group 3 to new group 6.

– Configurations are added to all groups.

4. Paragraph 1.C. Reason - New inspection areas added and 'Revision 2 is sent to' statement added.

5. Paragraph 1.D. Description - New inspection areas are added.

6. Paragraph 1.E. Compliance - Existing AD replaced by latest AD, compliance tables revised for new inspection areas and compliance tables added for installation of the preventative modification and for airplanes that previously installed a repair or preventative modification per Revision 1 or Revision 0 of this service bulletin.

7. Paragraph 1.F. Approval - Paragraph three revised for latest AD.

8. Paragraph 1.G. Manpower - Existing tables revised to show new inspection areas, and new table added for post modification inspection.

9. Paragraph 1.M. Software Accomplishment Summary added.

10. Paragraph 3.A. General Information - Added new notes.

11. Paragraph 3.B. Work Instructions - Existing steps revised to show added inspection, repair and preventative modification areas, and new steps added for post modification inspection instruction.

12. Figures 1, 2, 7 through 9, 10 through 18, 20, and 21 have updated group applicability.

13. Revised footnotes in Figures 7 through 9, and 13 through 15.

14. Revised footnotes and step tables in Figures 10 through 12.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 6 of 199 BOEING SERVICE BULLETIN 737-53A1279

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15. New figures 22 thru 26 added to show new inspection and preventative modification areas.

Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity and format changes, to show the location of all content changes.

Pages with no vertical lines have no changes.

REVISION HISTORY December 18, 2007Original Issue:

September 02, 2011Revision 1:

April 21, 2015Revision 2:

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 7 of 199 BOEING SERVICE BULLETIN 737-53A1279

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Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 8 of 199 BOEING SERVICE BULLETIN 737-53A1279

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Commercial Airplanes 737 Service Bulletin ALERT SummaryNumber: 737-53A1279Original Issue: December 18, 2007 Revision 2: April 21, 2015 ATA System: 5311 SUBJECT: FUSELAGE - Frames and Bulkheads - Forward Cargo Bay Stringer 19 to Stringer 22

- Frames and Frame Reinforcements - Inspection, Repair and Preventative Modification at Wire Penetration Hole, 0.50 Inch Diameter Hole, Standoff/Tooling Holes and Production Fastener Holes

THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH

1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER.

CONCURRENT REQUIREMENTS None.

BACKGROUND This service bulletin gives instructions to inspect a 1.04 inch nominal diameter wire penetration hole, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes for cracking in the forward cargo compartment frames and frame reinforcements, between Stringer (S) S-19 and S-22, on both left and right sides of the airplane. It also provides repair instructions for cracking at the 1.04 inch nominal diameter wire penetration hole, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes and instructions for a preventative modification. Undetected cracking in fuselage frames at the 1.04 inch nominal diameter wire penetration hole intended for wire routing, the 0.50 inch diameter hole, the standoff/tooling holes or the production fastener holes will reduce the frames structural capability below fail-safe load limits. Undetected cracking in the frames could lead to cracking in the skin and could result in rapid depressurization of the airplane.

Boeing has received reports of cracking in the frame, or in the frame and frame reinforcement, common to the

1.04 inch nominal diameter wire penetration hole intended for wire routing, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes, between S-19 and S-22, on both left and right sides of the airplane. The cracked frames are located between Station (STA) 500B and STA 520 on 737-300/400 airplanes and STA 482 and STA 520 on 737-500 airplanes.

Cracking is occurring at the 1.04 inch nominal diameter wire penetration hole, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes due to the effect of operating loads in combination with the stress concentration at the 1.04 inch nominal hole, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 9 of 199

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Boeing received a report of frame cracking from an operator at the 1.04 inch nominal diameter wire penetration hole on a 737-400 airplane. The airplane had one cracked frame. Boeing has since received reports of more than fifty cracked frames at the 1.04 inch nominal diameter wire penetration hole on more than twenty airplanes, all either 737-300 or 737-500 airplanes. The airplanes had accumulated between 35,832 and 66,694 flight cycles.

The cracking initiated at the 1.04 inch nominal diameter wire penetration hole and grew towards the inner chord.

Boeing received a report of four cracked frames at BS 500B, BS 500C, BS 500D and BS 520 in the forward cargo compartment between S-20L and S-21L on a 737-300 airplane. The cracks at BS 500B and BS 500C were completely through the frame and fail-safe chord. The BS 500B frame was also cracked on the right hand side. The airplane had 44,535 flight cycles and 44,876 flight hours. Though the airplane was above the AD and service bulletin threshold of 32,000 flight cycles, the cracking was discovered before the airplane had reached the compliance time of the AD and of the original issue of this service bulletin.

In total, Boeing has received more than 50 reports of frame cracking at the 1.04 inch nominal diameter wire penetration hole on 24 airplanes. Details of the cracking are as follows:

— The cracking occurred at three frame stations on 737-300 airplanes, on four frame stations on 737-500 airplanes, and at one frame station on one 737-400 airplane.

— Sixteen airplanes had cracking on multiple frames.

— 10 frames had cracking at adjacent frames.

— 43 frames had cracking only at the inboard side of the 1.04 inch nominal diameter wire penetration hole in the frame inner chord or in the frame and frame reinforcement inner chord.

— 3 frames had cracking at the outboard side of the 1.04 inch nominal diameter wire penetration hole in the frame and the frame reinforcement. 2 of these frames were severed.

— Some frames had additional cracking at either the standoff/tooling holes or at the 0.50 inch diameter hole positioned below the 1.04 inch nominal diameter wire penetration hole.

Boeing received a report of cracking common to the 0.50 inch diameter hole with no reported cracking common to the 1.04 inch nominal diameter wire penetration hole. Boeing has also received a report of cracking common to the standoff/tooling hole with no reported cracking common to the 1.04 inch nominal diameter wire penetration hole or the 0.50 inch diameter hole. Inspections of the 0.50 inch diameter hole and standoff/tooling holes were only required in accordance with previous revisions of this service bulletin if any crack was found at the 1.04 inch nominal diameter wire penetration hole. Boeing has received multiple reports of cracking common to the production fastener holes during installation of a repair in accordance with 737-300 SRM 53-00-07, 737-400 SRM 53-00-07, or 737-500 SRM 53-00-07 Repair 13. An Inspection for cracking of the area and any necessary repair will assure the structural integrity of the fuselage.

This service bulletin provides additional inspections for airplanes that didn't inspect production fastener holes before the installation of preventative modifications on frames located between Station (STA) 500B and STA 520 on 737-300/400 airplanes and STA 482 and STA 520 on 737-500 airplanes between March 12, 2012 and February 1, 2014. Inspections in PART 7 are required at frames that accomplished PART 5 - PREVENTATIVE MODIFICATION in accordance with Revision 1 of this bulletin because PART 5 states: "Do the repair as given in 737 SRM 53-00-07 Repair 13 except omit the steps in the Damage Removal Procedure". Between the dates of March 12, 2012 and February 1, 2014, the HFEC open hole inspections for the production fastener holes in the frame using 737 NDT Manual Part 6, 51-00-00 Procedure 16 was moved within 737 SRM 53-00-07 Repair 13 into Section 4.B. Damage Removal from Section 4.C. Installation of Repair Parts.

Boeing Service Related Problem (SRP) 737-SRP-53-0289 is related to this service bulletin.

Boeing Service Related Problem (SRP) 737-SRP-53-0377 is related to this service bulletin.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 10 of 199 BOEING SERVICE BULLETIN 737-53A1279

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The fuselage frames addressed in this service bulletin from STA 500B to STA 520 on 737-300/-400 airplanes, and from STA 482 to STA 520 on 737-500 airplanes between S-19 and S-22 have been determined to be structure that is susceptible to Widespread Fatigue Damage (WFD).

This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.

ReferenceAffectedPlanning Data Paragraph 1.A.2., Spares AffectedNoSpares Affected Paragraph 1.E., Compliance and Paragraph

1.F., Approval YesAD Related Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change Paragraph 1.I., Electrical Load DataNoElectrical Load Changed Paragraph 1.K., Publications AffectedNoPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/PartsNoKits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator YesOperator Supplied Parts/Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin YesSpecial Tooling Required ACTION Get access to the forward cargo bay. Remove the cargo handling system, if installed. Remove the wire shrouds, sidewall linings, aft bulkhead panels and insulation blankets, on both sides of the airplane to get access to frames STA 500B - STA 520 on 737-300 and -400 airplanes and STA 482 - STA 520 on 737-500 airplanes. Unscrew the power feeder cable guides as required and move them away from the hole. Do a High Frequency Eddy Current (HFEC) inspection and a Detailed inspection of the frame and frame reinforcement between Stringers S-19 and S-22 for cracking. If any crack is found at the 1.04 inch nominal diameter wire penetration hole, the

0.50 inch diameter hole, the standoff/tooling holes or the production fastener holes between Stringers S-19 and S-22 do a repair in accordance with this Service Bulletin. If no crack is found at the 1.04 inch nominal diameter wire penetration hole, the 0.50 inch diameter hole, the standoff/tooling holes and the production fastener holes, either accomplish the preventative modification in accordance with this service bulletin, or restore access, put the airplane back to a serviceable condition and do repeat inspections at the intervals given in Paragraph 1.E., Compliance.

Group 1-3:

If a preventative modification was accomplished in accordance with Revision 1 of this service bulletin between March 12, 2012 and February 1, 2014, make sure the production fastener holes in the frame and frame reinforcement common to the modification angles were inspected using the inspection procedure in accordance with 737-Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Procedure 16. If the pre-modification inspections of the production fastener holes were not performed, then do a HFEC inspection of the frame re-inforcement, the 1.04 inch nominal diameter hole, the 0.50 inch diameter hole, a detailed inspection of the frame where visible, and a Low Frequency Eddy Current (LFEC) inspection of the frame in accordance with Revision 2 of this service Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details.

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 11 of 199 BOEING SERVICE BULLETIN 737-53A1279

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bulletin in accordance with compliance times listed in Paragraph 1.E., Compliance. If the pre-modification inspections of the production fastener holes or the preventative modification were accomplished before 12 March 2012, or after 1 February 2014, then do a post-modification inspection in accordance with 737 Structural Repair Manual 737-300 SRM 53-00-07, 737-400 SRM 53-00-07, or 737-500 SRM 53-00-07 Repair 20 at the compliance times listed in Paragraph 1.E., Compliance.

Group 4-6:

If a preventative modification was accomplished in accordance with Revision 1 of this service bulletin between March 12, 2012 and February 1, 2014, make sure the production fastener holes in the frame and frame reinforcement common to the modification angles were inspected using the inspection procedure in accordance with 737-Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Procedure 16. If the pre-modification inspections of the production fastener holes were not performed, then do a HFEC inspection of the frame re-inforcement, the 1.04 inch nominal diameter hole, the 0.50 inch diameter hole, the fail safe chord, and a detailed inspection of the frame where visible in accordance with Revision 2 of this service bulletin in accordance with compliance times listed in Paragraph 1.E., Compliance. If the pre-modification inspections of the production fastener holes or the preventative modification were accomplished before 12 March 2012, or after 1 February 2014, then do a post-modification inspection in accordance with 737 Structural Repair Manual737-300 SRM 53-00-07, 737-400 SRM 53-00-07, or 737-500 SRM 53-00-07 Repair 20 at the compliance times listed in Paragraph 1.E., Compliance.

EFFECTIVITY All 737-300/400/500 Series Airplanes. Refer to Paragraph 1.A.1 Airplanes, for the list of affected airplanes.

COMPLIANCE Federal Aviation Administration (FAA) Airworthiness Directive AD 2011-23-05 is related to this service bulletin.

See Service Bulletin Paragraph 1.E., for compliance information.

INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the inspection, and/or repair procedures given in this service bulletin.

MANPOWER See Service Bulletin Paragraph 1.G., for manpower information.

MATERIAL INFORMATION Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability .

Original Issue: December 18, 2007 737-53A1279Revision 2: April 21, 2015 12 of 199 BOEING SERVICE BULLETIN 737-53A1279

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