### Commercial **Airplanes** 

# 717 Service Bulletin **ALERT Number: 717-55A0011**  Original Issue: May 17, 2011 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Inspect/Repair/Replace Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 730-774). 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. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2011 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work. This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124. 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, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery 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.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 1 of 49 2.0BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 2 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**

BLANK PAGE**Table of Contents** Summary...................................................... 5 1. PLANNING INFORMATION ........................................ 9 A. Effectivity................................................ 9 1. Airplanes............................................. 9 2. Spares Affected ......................................... 9 B. Concurrent Requirements....................................... 9 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1. Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2. Data supplied with this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3. Installation Drawings Used in the Preparation of this Service Bulletin. . . . . . . . . . . . 15 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 C. Parts Necessary For Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2. Parts and Materials Supplied by the Operator. . . . . . . . . . . . . . . . . . . . . . . . 18 3. Parts Modified and Reidentified. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 18 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 FIGURE 1: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS . 23 FIGURE 2: CRACK LENGTH MEASUREMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 FIGURE 3: BLEND OUT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 FIGURE 4: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS . 40 APPENDIX A: TEMPLATE/SHIELD SHOP AID. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 3 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 4 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**

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### Commercial **Airplanes** 

# 717 Service Bulletin **ALERT Summary**  **Number: 717-55A0011** Original Issue: May 17, 2011 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Inspect/Repair/Replace Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs
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** Boeing has received reports of cracks found on either the left, right, or in few instances both, of the horizontal stabilizer center section ribs on MD-80 and MD-90 airplanes. Two cracks were reported on MD-80 airplanes with between 23,700 and 41,963 flight-hours and 23,300 and 35,294 flight cycles. Nine cracks were reported on MD-90 airplanes with between 9,051 and 26,053 flight-hours and 8,939 and 25,260 flight cycles. These cracks were found on the aft face of the horizontal stabilizer hinge bearing lugs. Although there have been no reports of cracks found on 717 airplanes, they utilize the same rib design as the MD-80 and MD-90 airplanes, and are susceptible to the same failure mode. Investigation by Boeing has yet to establish the definitive cause of these cracks. Performing an Eddy Current, High Frequency (ETHF) inspection of the affected area will determine the existence of any crack. Doing a blend out repair of any existing crack within repair limits will help minimize crack growth. If not corrected, undetected cracks in the center section left and right rib hinge bearing lugs could spread at the same time, which would cause both hinge bearing lugs to fail, resulting in the inability of the horizontal stabilizer to sustain flight loads and consequent reduced controllability of the airplane. **ACTION** This service bulletin provides instructions to do an ETHF inspection for cracks on the horizontal stabilizer center section left and right rib hinge bearing lugs. Refer to Paragraph 1.D., Description for the required corrective action based on the results of the inspection. **EFFECTIVITY** 717-200 Airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 5 of 49**COMPLIANCE** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Refer to Paragraph 1.E., Compliance. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the inspection, repair and/or replacement procedures given in this service bulletin. **MANPOWER** Refer to Paragraph 1.G., Manpower. **MATERIAL INFORMATION** Boeing Supplied Kits/Parts. Refer to Paragraph 2.A., Material - Price and Availability.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 6 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 7 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 8 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**

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### Commercial **Airplanes** 

# 717 Service Bulletin **ALERT Number: 717-55A0011**  Original Issue: May 17, 2011 ATA System: 5510 **SUBJECT:** STABILIZERS - Horizontal Stabilizer - Inspect/Repair/Replace Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs
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. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes This service bulletin is for the airplanes shown below.
**DESCRIPTION CONFIGURATION**  **GROUP** Inspect Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs on 717-200 airplanes. - 1

Airplane Models:
717-200 **Group Fuselage Num-**  **ber** 1 5002 - 5156 2. Spares Affected None. **B. Concurrent Requirements** None.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 9 of 49**C. Reason** Boeing has received reports of cracks found on either the left, right, or in few instances both, of the horizontal stabilizer center section ribs on MD-80 and MD-90 airplanes. Two cracks were reported on MD-80 airplanes with between 23,700 and 41,963 flight-hours and 23,300 and 35,294 flight cycles. Nine cracks were reported on MD-90 airplanes with between 9,051 and 26,053 flight-hours and 8,939 and 25,260 flight cycles. These cracks were found on the aft face of the horizontal stabilizer hinge bearing lugs. Although there have been no reports of cracks found on 717 airplanes, they utilize the same rib design as the MD-80 and MD-90 airplanes, and are susceptible to the same failure mode. Investigation by Boeing has yet to establish the definitive cause of these cracks. Performing an Eddy Current, High Frequency (ETHF) inspection of the affected area will determine the existence of any crack. Doing a blend out repair of any existing crack within repair limits will help minimize crack growth. If not corrected, undetected cracks in the center section left and right rib hinge bearing lugs could spread at the same time, which would cause both hinge bearing lugs to fail, resulting in the inability of the horizontal stabilizer to sustain flight loads and consequent reduced controllability of the airplane. **D. Description** This service bulletin provides instructions to do an ETHF inspection for cracks on the horizontal stabilizer center section left and right rib hinge bearing lugs, and does as follows: **CONDITION 1 (No Crack Found in Rib Hinge Bearing Lug)** 1. Does repeat ETHF inspection. **CONDITION 2 (Crack Found in Rib Hinge Bearing Lug)** 1. Measures the length of the crack and does as follows:
**CONDITION 2A (Crack Length Between Points 'A' and 'B' is Less Than or Equal to 0.15 Inch, AND Crack Length Between Points 'C' and 'D' is Less Than or Equal to 0.05 Inch)**  a. Does blend out repair to remove crack. b. Does repeat ETHF inspection of the blend out area. **CONDITION 2B (No Crack Found During ETHF Inspection After Blend Out Repair)** (1) Does repeat ETHF inspection of the blend out area. **CONDITION 2C (Crack Found During ETHF Inspection After Blend Out Repair)** (1) Removes cracked horizontal stabilizer center section rib and installs new horizontal stabilizer center section rib. (2) Does ETHF inspection of the horizontal stabilizer center section rib hinge bearing lug.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 10 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT CONDITION 2D (Crack Length Between Points 'A' and 'B' is Greater Than 0.15 Inch, OR**  **Crack Length Between Points 'C' and 'D' is Greater Than 0.05 Inch)** a. Removes cracked horizontal stabilizer center section rib and installs new horizontal stabilizer center section rib. b. Does ETHF inspection of the horizontal stabilizer center section rib hinge bearing lug. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 351, 361 717-200 **E. Compliance** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. **Table 1 - Inspect Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs for Cracks: Repeat Interval**  **(Not to Exceed) Compliance Time (Whichever**  **Occurs Later) Action**  **Condition**

- Within 8,275flight cycles after the original issue date onthis service bulletin.Before the accumulation of 35,000 total flight cycles. Do an ETHF inspectionof the aft face of the horizontal stabilizer center section left and right ribhinge bearing lugs in accordance with Paragraph 3.B.2., Work Instructions. All Airplanes

10,500 flight cycles. Within 10,500 flight cycles from last inspection. Do an ETHF inspectionof the aft face of the uncracked horizontal stabilizer center section rib hinge bearing lug in accordance with Paragraph 3.B.2., Work Instructions. CONDITION 1 (No Crack Found in Rib Hinge Bearing Lug)

- Before further flight. Measure the length of the crack in accordance with Paragraph 3.B.2., Work Instructions. CONDITION 2 (Crack Found In Rib Hinge Bearing Lug)

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 11 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT Table 1 - Inspect Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs for Cracks:**  **Repeat Interval (Not to Exceed)**  **Compliance Time (Whichever Occurs Later)**  **Action Condition** 

- Before further flight. Do blend out repair in ac- cordance with Paragraph 3.B.2., Work Instructions. CONDITION 2A (Crack Length Between Points 'A' and 'B' is Less Than or Equal to 0.15 Inch,AND Crack Length Between Points 'C' and 'D' is Less Than or Equal to 0.05 Inch.) AND

- Within 14,200 flight cycles after blend out repair. Do an ETHF inspection of the blend out area on the horizontal stabilizer center section rib hinge bearing lug in accordance with Paragraph 3.B.2., Work Instructions. 5,400 flight cycles.

- Do repetitive ETHF in- spection of the blend out area on the horizontal stabilizer center section rib hinge bearing lug inaccordance with Paragraph 3.B.2., Work Instructions. CONDITION 2B (No Crack Found During ETHF Inspection After Blend Out Repair)

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 12 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT Table 1 - Inspect Horizontal Stabilizer Center Section Left and Right Rib Hinge Bearing Lugs for Cracks:**  **Repeat Interval (Not to Exceed)**  **Compliance Time (Whichever Occurs Later)**  **Action Condition** 

- Before further flight. Remove cracked horizon-tal stabilizer center section rib and install newhorizontal stabilizer center section rib in accordance with Paragraph 3.B.2., Work Instructions. CONDITION 2C (Crack Found During ETHF Inspection After Blend Out Repair)

AND

- Within 35,000 flight cycles after the installation of the new rib. Do an ETHF inspectionof the aft face of the horizontal stabilizer center section rib hinge bearing lug in accordance with Paragraph 3.B.2., Work Instructions. AND

- At the applicable compliance times specified in CONDITION 1 or CONDITION 2 of this table. Do the applicable actions specified in CONDITION 1 or CONDITION 2 of this table.

- Before further flight. Remove cracked horizon-tal stabilizer center section rib and install newhorizontal stabilizer center section rib in accordance with Paragraph 3.B.2., Work Instructions. CONDITION 2D (Crack Length Between Points 'A' and 'B' is Greater Than 0.15 Inch, OR Crack Length Between Points 'C' and 'D' is Greater Than 0.05 Inch.) AND

- Within 35,000 flight cycles after the installation of the new rib. Do an ETHF inspectionof the aft face of the horizontal stabilizer center section rib hinge bearing lug in accordance with Paragraph 3.B.2., Work Instructions. AND

- At the applicable compliance times specified in CONDITION 1 or CONDITION 2 of this table. Do the applicable actions specified in CONDITION 1 or CONDITION 2 of this table.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 13 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT F. Approval**  This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. **G. Manpower** The table below shows an estimate of the task hours necessary to do this inspection for each airplane. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task hour data if necessary. The estimate does not include lost time. These are some examples of lost time: • Time to adjust to the workplace • Time to schedule the work • Time to inspect the work • Time to cure the materials • Time to make the parts • Time to find the tools. **Elapsed Hours Task Hours**  **Number of Persons Task**  1.0 2.0 2 Open Access 2.0 2.0 1 FIGURE 1 1.0 2.0 2 Close Access 4.0 6.0 TOTAL FOR EACH AIRPLANE
**NOTE:** The Manpower totals listed do not include the hours required to accomplish any blend out repair(s) or replacement of center section rib(s), if required. Operators are to estimate the task hours required based on inspection results. **H. Weight and Balance Changes** None. **I. Electrical Load Data** Not changed.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 14 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT J. References**  1. Existing Data a. Boeing Service Bulletin MD90-55A016. b. Boeing Service Bulletin MD80-55A069. c. Non-Destructive Test Standard Practices Manual (NDTSPM) 06-10-01.001. d. 717 Aircraft Maintenance Manual (AMM) 06-33-00. e. 717 Structural Repair Manual (SRM) 51-10-04. 2. Data supplied with this Service Bulletin None. 3. Installation Drawings Used in the Preparation of this Service Bulletin **Change Title**  **Document Number** C Memo 2 RIB CRACK REPAIR - HORIZ STAB, STA XH=6.625 SR90550001

This drawing was used to prepare this service bulletin. This drawing is not necessary to make the specified changes, and is not supplied with this service bulletin. This drawing may not be applicable to all airplane configurations or operators. **K. Publications Affected** 1. Publications: None. 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin affects FCS. DTI requirements for the structure affected are contained in Paragraph 1.E., Compliance of this service bulletin. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 15 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 16 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**

BLANK PAGE**2. MATERIAL INFORMATION A. Material - Price and Availability**  **NOTE:** Parts are only required for Condition 2C or 2D. Boeing can supply the kits/parts shown in Paragraph 2.C., Parts Necessary for Each Airplane if needed, as shown below. If there is a limit to the quantity of available parts, a supply sequence is given by Spares. More parts become available as shown in the Reorder Lead Time (ROLT). Operators are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin. **REFER TO THE BOEING PART PAGE ON MYBOEINGFLEET.COM OR CONTACT FIRST RESPONDER AT FR@BOEING.COM FOR THE LATEST REORDER LEAD TIME (ROLT) AND PRICE INFORMATION**  **Unit Price (US Dollars)**  **ROLT (Calendar Days)**  **Name Part Number**  $16,387.00 120 RIB - HORIZ STAB, STA XH=6.625 (LEFT) 9911846-513 16,387.00 120 RIB - HORIZ STAB, STA XH=6.625 (RIGHT) 9911846-514 The parts are subject to the terms and conditions of the Boeing standard purchase order acknowledgment. Prices are in United States Dollars. Terms: Net 30 days. Reference this service bulletin and submit your purchase order by one of these methods: 1. Order on-line via ATA Spec 2000 or The Boeing Part Page 2. Fax to (206) 662-7145 **B. Industry Support Information** Boeing warranty remedies are not available for the inspection, repair and/or replacement procedures given in this service bulletin. **C. Parts Necessary For Each Airplane** 1. Kits/Parts **NOTE:** Parts are only required for Condition 2C or 2D. To get the parts shown below, refer to Paragraph 2.A., Material - Price and Availability. **Existing Part Number**  **Name QTY**  **New Part Number**

9911846-513 RIB - HORIZ STAB, STA XH=6.625 (LEFT) 1 9911846-513

9911846-514 RIB - HORIZ STAB, STA XH=6.625 (RIGHT) 1 9911846-514

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 17 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**2. Parts and Materials Supplied by the Operator None. 3. Parts Modified and Reidentified None. 4. Parts Removed and Not Replaced None. **D. Parts Necessary to Change Spares** None. **E. Special Tooling - Price and Availability** The operator can supply the tools shown in Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin. Tool price and supply data are not given. **F. Special Tooling Necessary to do this Service Bulletin** No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 18 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT 3. ACCOMPLISHMENT INSTRUCTIONS**  **A. GENERAL INFORMATION WARNING:**  IF ELECTRICAL POWER IS APPLIED TO THE AIRPLANE, MAKE SURE YOU OBEY ALL PRECAUTIONS WHILE YOU DO WORK. IF YOU DO NOT OBEY THE PRECAUTIONS, DEATH OR INJURY TO PERSONS, AND DAMAGE TO THE AIRPLANE CAN OCCUR. **CAUTION:** ELECTRICALLY GROUND THE AIRPLANE. THIS WILL HELP TO PREVENT DAMAGE TO THE AIRPLANE OR EQUIPMENT. **CAUTION:** KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. **NOTE:** 1. The instructions identified in Paragraph 3.B., Work Instructions, and the Figure(s) give the recommended sequence of steps. The sequence of steps to do this service bulletin can be changed. 2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 3. Equivalent parts are listed in the AEPL, Drawing 7595071. 4. Use the approved fastener and process material substitutions, in accordance with Structural Repair Manual (SRM) 51. 5. If the length of any fastener specified in this service bulletin does not meet installation standards given in SRM Chapter 51, then a fastener of the same specification, or an approved substitute, with a length which meets the installation standards given in SRM Chapter 51 may be used. In addition, washers may be installed for fastener grip length in accordance with SRM Chapter 51. 6. Unless shown differently, these dimensions and tolerances are used: – Linear dimensions are in inches – Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or minus 0.03 inch. – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees 7. Obey all of the warnings and cautions given in the specified manual sections. 8. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 19 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**9. Some Boeing parts are supplied in a temporary configuration. Those parts are identified with a 'U' or 'Y' in place of the '-' (dash) in the part number. It is permitted to install parts identified with a 'U' or 'Y' as an alternative to the '-' (dash) number part. Boeing Drawing SE10000000, Sheets 5.0 and 6.0 contain more data. 10. The instructions in Paragraph 3.B., Work Instructions and the figures can include operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain data on versions of the tools or test equipment that you can use. It is permitted to use replaced tools. It is not permitted to use superseded tools. 11. If it is necessary to remove more parts for access, you can remove those parts. If you can get access without removing identified parts, it is not necessary to remove all of the identified parts. Jacking and shoring limitations must be observed. 12. Where the work instructions include installation of a kept part, a new or serviceable part with the same part number can be installed as an alternative to the kept part. The removed part can be discarded if a new or serviceable part is installed. 13. This service bulletin includes functional test procedures for the systems changed by this service bulletin. More functional tests can possibly be necessary in accordance with standard maintenance practices because of interruption to other airplane systems. **B. WORK INSTRUCTIONS** 1. Remove and keep access panels. Refer to 717 AMM 06-33-00.
**Location Access Panel**  Left side lower horizontal stabilizer fairing 350AB Right side lower horizontal stabilizer fairing 360AB 2. Do an Eddy Current, High Frequency (ETHF) inspection for cracks, on the aft face of the horizontal stabilizer center section left and right rib hinge bearing lugs, in accordance with FIGURE 1 and do as follows:
**CONDITION 1 (No Crack Found in Rib Hinge Bearing Lug)** a. Install kept access panels. Refer to 717 AMM 06-33-00.
**Location Access Panel**  Left side lower horizontal stabilizer fairing 350AB Right side lower horizontal stabilizer fairing 360AB b. Put the airplane back to a serviceable condition. c. Report inspection results, both positive and negative, fuselage number, and cycles and flight-hours of affected airplane, through your local field service representative or by one of the methods that follow:

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 20 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**— Mail: Boeing - Long Beach Division P.O. Box 1771 Long Beach, California 90801 Attn: Senior Manager Technical and Fleet Support Structures/Payloads & Repair Design ATA CODE: 5510 Service Engineering D800-0032 (Service Bulletin 717-55A0011) — Email: dse.boecom@boeing.com ATA CODE: 5510 — Fax: Long Beach Service Engineering FAX: (206) 766-5683 ATA CODE: 5510 d. Do an ETHF inspection, in accordance with FIGURE 1, of the aft face of the uncracked horizontal stabilizer center section rib hinge bearing lug, at intervals in accordance with Paragraph 1.E., Compliance. **CONDITION 2 (Crack Found in Rib Hinge Bearing Lug)** a. Measure the length of the crack in accordance with FIGURE 2 and do as follows: **CONDITION 2A (Crack Length Between Points 'A' and 'B' is Less Than or Equal To 0.15 Inch AND Crack Length Between Points 'C' and 'D' is Less Than or Equal To 0.05 Inch)**  (1) Report inspection results, both positive and negative, fuselage number, and cycles and flight-hours of affected airplane, through your local field service representative or by one of the methods that follow: — Mail: Boeing - Long Beach Division P.O. Box 1771 Long Beach, California 90801 Attn: Senior Manager Technical and Fleet Support Structures/Payloads & Repair Design ATA CODE: 5510 Service Engineering D800-0032 (Service Bulletin 717-55A0011) — Email: dse.boecom@boeing.com ATA CODE: 5510 — Fax: Long Beach Service Engineering FAX: (206) 766-5683 ATA CODE: 5510 (2) Do blend out repair in accordance with FIGURE 3. **NOTE:** Drawings for a locally manufactured template/shield shop aid that can be used to help define the blend out area are available in APPENDIX A. (3) Install kept access panels. Refer to 717 AMM 06-33-00.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 21 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT Location**  **Access Panel** Left side lower horizontal stabilizer fairing 350AB Right side lower horizontal stabilizer fairing 360AB(4) Put the airplane back to a serviceable condition. (5) Do an ETHF inspection of the blend out area on the horizontal stabilizer center section rib hinge bearing lug in accordance with FIGURE 4, at intervals in accordance with Paragraph 1.E., Compliance. **CONDITION 2B (No Crack Found During ETHF Inspection After Blend Out Repair)** (a) Do repeat ETHF inspection of the blend out area. **CONDITION 2C (Crack Found During ETHF Inspection After Blend Out Repair)** (a) Remove cracked horizontal stabilizer center section rib and install new horizontal stabilizer center section rib. (b) Do an ETHF inspection for cracks, on the aft face of the horizontal stabilizer center section rib hinge bearing lug, in accordance with FIGURE 1, and do the applicable actions specified in CONDITION 1 or CONDITION 2, at compliance times and intervals in accordance with Paragraph 1.E., Compliance. **CONDITION 2D (Crack Length Between Points 'A' and 'B' is Greater Than 0.15 Inch OR Crack Length Between Points 'C' and 'D' is Greater Than 0.05 Inch)**  (1) Remove cracked horizontal stabilizer center section rib and install new horizontal stabilizer center section rib. (2) Do an ETHF inspection for cracks, on the aft face of the horizontal stabilizer center section rib hinge bearing lug, in accordance with FIGURE 1, and do the applicable actions specified in CONDITION 1 or CONDITION 2, at compliance times and intervals in accordance with Paragraph 1.E., Compliance.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 22 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 1: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS**  **(SHEET 1 OF 4)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 23 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 1: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS**  **(SHEET 2 OF 4)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 24 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 1: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS**  **(SHEET 3 OF 4)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 25 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**The step number shown below agree with the number shown in the circle symbol in the figure.
**Action Step**  Do an ETHF surface inspection of the rib at the hinge bearing lug aft radius at approximately Stations Yh=76.000 and Xh=6.625. Scan the lug radius as shown, looking for cracks propagating across the radius. Refer to NDTSPM 06-10-01.001 (ETHF - Procedure 1). Use Calibration Method "G" and Scan Method "69". 1

Do an ETHF surface inspection of the rib at the hinge bearing lug aft radius at approximately Stations Yh=76.000 and Xh=6.625. Scan the lug radius as shown, slightly above the scan done in Step 1, looking for cracks propagating in the vertical direction. Refer to NDTSPM 06-10-01.001 (ETHF - Procedure 1). Use Calibration Method "C" and Scan Method "62". 2

**FIGURE 1: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS (SHEET 4 OF 4)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 26 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 2: CRACK LENGTH MEASUREMENT**  **(SHEET 1 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 27 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 2: CRACK LENGTH MEASUREMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 28 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**Action Step**  Measure the crack length from end point (Point A) to where crack intersects the chamfer (Point B) on the outboard face of the hinge lug. Do not include the measurement of crack length in chamfer. Record measurement. 1

Measure the crack length from end point (Point D) to where crack intersects the chamfer (Point C) on the aft face of the hinge lug. Do not include measurement of crack length in the chamfer. Record measurement. 2

**FIGURE 2: CRACK LENGTH MEASUREMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 29 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 1 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 30 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 2 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 31 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 3 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 32 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 4 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 33 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 5 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 34 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 6 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 35 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 7 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 36 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 8 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 37 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 3: BLEND OUT REPAIR**  **(SHEET 9 OF 10)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 38 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
**Action Step**  Locate Point 1. Point 1 is identified as the intersecting point of a line offset from the horizontal stabilizer lower surface 0.050 inch, and the outboard edge of the chamfer on the hinge lug. 1 Locate Point 2. Point 2 is identified as the point on a line offset from the horizontal stabilizer lower surface 0.050 inch, and 0.58 inch forward of Point 1. 2 Locate Point 4. Point 4 is identified as the point located 1.59 inch measured normal to the horizontal stabilizer lower surface at the aft edge of the hinge lug. 3 Locate Point 3. Point 3 is identified as the point located 0.19 inch from the inboard edge of the hinge lug, and 0.50 inch from the horizontal stabilizer lower surface. 4 Blend out the crack. (Blend 'A') Do not exceed the limits of the area defined by points 1, 2, 3, and 4. The blend out should form a "V" shape, with the deepest portion of the "V" being in the area of the crack, and approximately 127 degrees between the legs of the "V". Maintain a 0.25 inch radius at the bottom of the "V". The majority of the blend should be at approximately 45 degrees from the outboard face of the lug. It is recommended that a 0.50 inch diameter ball grinder be used to do the blend out. Remove only enough material to remove the crack. Do not remove more than 0.25 inchof material total depth as measured from a line drawn between the points B and C that were established in Figure 2. 5

Do ETHF inspections during material removal to verify crack has been removed. Scan the blend out as shown, looking for cracks in the upper forward to lower aft direction. Scan the blend out and give more attention to the outside periphery. Refer to NDTSPM 06-10-01.001 (ETHF - Procedure 1). Use Calibration Method "G" and Scan Method "69". If crack still is not removed, repeat Steps 5 and 6. 6

Once the crack has been removed, remove an additional 0.050 inch of material to ensure that a crack that is too small to detect has been removed. Finish blend out to a 63 micro-inch finish. 7 Do a taper of the outboard face of the lug. (Blend 'B') The taper begins at a line between Point 4 and tangent to the radius on the aft portion of the bearing lug surface, and extends upward and aft to a point 1.65 inches above Point 4. Finish blend out to a 63 micro-inch finish. 8

Break all reworked edges to a 0.12 inch radius. If adjacent structure prevents using a 0.12 inch radius, use the largest radius possible in the area. 9 Apply corrosion protection to the rework area. Refer to 717 SRM 51-10-04. 10 (Not S

h o w

n )

**FIGURE 3: BLEND OUT REPAIR (SHEET 10 OF 10)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 39 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT FIGURE 4: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS**  **(SHEET 1 OF 2)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 40 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**The step number shown below agree with the number shown in the circle symbol in the figure.
**Action Step**  Do an ETHF surface inspection of Blend 'A' area at the hinge bearing lug aft radius. Scan the blend out as shown, looking for cracks in the upper forward to lower aft direction. Scan the blend out and give more attention to the outside periphery. Refer to NDTSPM 06-10-01.001 (ETHF - Procedure 1). Use Calibration Method "G" and Scan Method "69". 1

**FIGURE 4: INSPECT HORIZONTAL STABILIZER CENTER SECTION RIB HINGE BEARING LUGS (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 41 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**This appendix provides instructions for the fabrication and usage of a template/shield shop aid to assist in simplifying the identification of the extents of the blend out area, if required, identified in FIGURE 3. This appendix provides instructions to build a template/shield for use on the left hand hinge bearing lug. A mirror image template/shield is required for the right hand hinge bearing lug. **FABRICATION** 1. Fabricate all parts from 0.050 Inch CRES Sheet, Type 321, per Aerospace Material Specification (AMS) 5510 or equivalent. 2. Identification of parts and assemblies at operator's option, and per operator's shop practice. 3. Fusion weld with Gas Tungsten Arc Welding (GTAW). 4. It is acceptable to fusion weld from opposite side than that specified by the welding symbol. 5. If surfaces on -3 and -9 parts are distorted by welding, straighten surfaces to within +/- .010 inch before use. 6. Tack or continuous weld -11 to the sub assembly from sub-assembly step 3. 7. Trim -7 as shown. 8. Cut or grind radius on -7 as shown. 9. Unless shown differently, these dimensions and tolerances are used for the fabrication of a template/shield shop aid: – Linear dimensions are in inches. – Angular tolerance is plus or minus 0 degrees, 30 minutes. – Tolerance on 3 place decimal linear dimension is plus or minus 0.015 inch. – Tolerance on 2 place decimal linear dimension is plus or minus 0.03 inch.

**APPENDIX A: TEMPLATE/SHIELD SHOP AID (SHEET 1 OF 8)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 42 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 2 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 43 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 3 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 44 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 4 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 45 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 5 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 46 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 6 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 47 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT DIRECTIONS FOR TEMPLATE/SHIELD SHOP AID USE**  1. After identifying points 1, 2, 3, and 4 in accordance with the instructions in FIGURE 3, place template/shield on lug. Push upper portion of template/shield against the lower surface of the horizontal stabilizer, and push the outer portion of the template/shield against the outboard surface of the lug. 2. Slide the template/shield fore and aft until the lower portion of the template is on Point 4, and check that the template/shield is aligned with Point 2. **NOTE:** The aft face of the template/shield may not be in contact with the aft face of the lug when the template/shield is aligned with Points 2 and 4. 3. Using an appropriate marker, trace the template/shield shape on the aft face of the lug, and on the outboard face of the lug, to visually define the shape of the blend out area. Do not exceed the limits of the blend out area defined by Points 1, 2, 3, and 4 established in FIGURE 3 if they are different than the area defined by the template/shield. The template/shield may be secured to the lug and used as a shield to help while grinding the crack out in accordance with FIGURE 3.

**APPENDIX A: TEMPLATE/SHIELD SHOP AID (SHEET 7 OF 8)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 48 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT APPENDIX A: TEMPLATE/SHIELD SHOP AID**  **(SHEET 8 OF 8)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: May 17, 2011 717-55A0011 49 of 49 **BOEING SERVICE BULLETIN 717-55A0011 ALERT**  **ALERT**