### Commercial **Airplanes** 

# 727 Service Bulletin **SPECIAL ATTENTION Number: 727-55-0095**  Original Issue: September 24, 2012 ATA System: 5500 **SUBJECT:** STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection 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. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2012 Boeing. Unpublished Work. All Rights Reserved. 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, DreamlinerTM, 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 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. BOEING is a trademark of Boeing Management Company.

Original Issue: September 24, 2012 727-55-0095 1 of 27 4.0Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 2 of 27 **BOEING SERVICE BULLETIN 727-55-0095**

BLANK PAGE**Table of Contents** Summary...................................................... 5 1. PLANNING INFORMATION ........................................ 9 A. Effectivity................................................ 9 1. Airplanes............................................. 9 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2. Data Supplied with this Service Bulletin:. . . . . . . . . . . . . . . . . . . . . . . . . . . 16 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 16 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 17 M. Software Accomplishment Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 C. Parts Necessary for Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1. Kits/Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2. Parts and Materials Supplied by the Operator. . . . . . . . . . . . . . . . . . . . . . . . 19 3. Parts Modified and Reidentified. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4. Parts Removed and Not Replaced. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 20 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION. . . . 24 FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION . . . 26

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 3 of 27 **BOEING SERVICE BULLETIN 727-55-0095**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 4 of 27 **BOEING SERVICE BULLETIN 727-55-0095**

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### Commercial **Airplanes** 

# 727 Service Bulletin **SPECIAL ATTENTION Summary**  **Number: 727-55-0095** Original Issue: September 24, 2012 ATA System: 5500 **SUBJECT:** STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **CONCURRENT REQUIREMENTS** None. **BACKGROUND** This service bulletin gives instructions to inspect the left side and right side chords of the fin closure rib for cracking or corrosion. The fin closure rib is located at the top of the vertical fin structure. The chords of the fin closure rib support the horizontal stabilizer hinge fittings. If the work in this service bulletin is not done, widespread cracking in the chords may weaken the fin closure rib structure which could result in loss of airplane control due to lack of horizontal stabilizer support. One operator reported finding a crack on the left side chord of the fin closure rib during a routine maintenance inspection. The crack measured a maximum of 2.4 inches long and it ran along the length of the chord. The airplane had accumulated 5,303 flight cycles and 11,669 flight hours when the crack was found. Cracking at this location is the result of intergranular stress corrosion caused by the material properties of 2024-T351 extrusion from which the closure rib chord is made. This material becomes vulnerable after the surface finishes begin to break down as a result of normal in-service aging. A fleet history search revealed that this occurrence is the first report of intergranular cracking of the chords. The Corrosion Prevention and Control Program (CPCP) and Maintenance Planning Data (MPD) documentation for 727 airplanes both contain visual inspections of the chords, but no NDT inspections. Accomplishment of the NDT and visual inspections in this service bulletin will make sure that any crack or corrosion in the left side or right side chords of the fin closure rib is detected. Boeing Service Related Problem (SRP) 727-SRP-55-0050 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 727 FTD 55-10001 is related to this service bulletin. This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.
**Reference Affected**  **Planning Data** Paragraph 1.A.2., Spares Affected No Spares Affected Paragraph 1.E., Compliance No AD Related

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 5 of 27**Reference Affected**  **Planning Data** Paragraph 1.H., Weight and Balance Changes No Weight and Balance Change Paragraph 1.I., Electrical Load Data No Electrical Load Changed Paragraph 1.K., Publications Affected No Publications Affected Paragraph 1.K., Publications Affected No Airplane Flight Operations Affected (Flight CrewOperations Manual and/or FAA Approved Airplane Flight Manual) Paragraph 2.C.1., Kits/Parts No Kits/Parts Required Paragraph 2.C.2., Parts and Materials Supplied by the Operator Yes Operator Supplied Material Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin No Special Tooling Required

**ACTION** Get access to the left side and right side chords of the fin closure rib by opening access panels at the fin closure rib. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC) inspections for any crack in the left side and right side chords. If any crack or corrosion is found, contact Boeing for repair or replacement instructions and do the work instructed by Boeing. Do repeat inspections at the interval given in Paragraph 1.E., Compliance. **EFFECTIVITY** All 727, 727-100, 727-100C, 727-200, 727-200F, 727C airplanes. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes. **COMPLIANCE** Refer to Paragraph 1.E., Compliance. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the inspection procedures given in this service bulletin. **MANPOWER** Refer to Paragraph 1.G., Manpower. **Elapsed Hours Total Task Hours**  **Airplanes** 11.00 17.00 Group 1
**MATERIAL INFORMATION** Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 6 of 27 **BOEING SERVICE BULLETIN 727-55-0095**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 7 of 27 **BOEING SERVICE BULLETIN 727-55-0095**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 8 of 27 **BOEING SERVICE BULLETIN 727-55-0095**

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### Commercial **Airplanes** 

# 727 Service Bulletin **SPECIAL ATTENTION Number: 727-55-0095**  Original Issue: September 24, 2012 ATA System: 5500 **SUBJECT:** STABILIZERS - Vertical Stabilizer - Fin Closure Rib - Chord Inspection BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes Refer to Service Bulletin Index D6-9825 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplane(s) shown below.
**DESCRIPTION CONFIGURATION**  **GROUP** All 727, 727-100, 727-100C, 727-200, 727-200F, 727C airplanes.

- 1

Airplane Models: 727, 727-100, 727-100C, 727-200, 727-200F, 727C **Group Variable Number**  1 E0001 - E0042 1 E0101 - E0140 1 E0201 - E0216 1 E0301 - E0351 1 E0401 - E0423 1 E3001 - E3006 1 E3011 - E3014 1 E3021 - E3040 1 E3059

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 9 of 27**Group Variable Number**  1 E3061 - E3077 1 E3101 - E3103 1 E3111 - E3118 1 E3141 - E3152 1 E3171 - E3177 1 E3201 - E3206 1 E3221 - E3224 1 E3241 - E3290 1 E3341 - E3350 1 E3401 - E3421 1 E3451 - E3452 1 E3471 - E3474 1 E3501 - E3513 1 E3516 - E3523 1 E3551 - E3553 1 E3571 - E3578 1 E3601 - E3604 1 E3621 - E3622 1 E3651 - E3655 1 E3677 1 E3681 - E3684 1 E3701 - E3704 1 E3751 - E3755 1 E3781 - E3784 1 E5001 - E5011 1 E5031 - E5068 1 E5101 - E5116 1 E5141 - E5143 1 E5161 - E5164 1 E5201 - E5203 1 E5221 - E5245 1 E5251 - E5252 1 E5271 - E5281

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 10 of 27 **BOEING SERVICE BULLETIN 727-55-0095 Group**  **Variable Number** 1 E5301 - E5306 1 E5351 - E5353 1 E5381 - E5382 1 E5401 - E5424 1 E5426 - E5429 1 E5433 1 E5435 1 E5451 - E5455 1 E5481 - E5483 1 E5501 - E5502 1 QA001 - QA046 1 QA051 - QA099 1 QA101 - QA199 1 QA201 - QA225 1 QA301 - QA349 1 QA351 - QA376 1 QA378 1 QA401 - QA499 1 QA501 - QA537 1 QA551 - QA579 1 QA581 - QA585 1 QA601 - QA688 1 QA701 - QA753 1 QA801 - QA805 1 QA851 - QA899 1 QA901 - QA946 1 QA949 1 QB001 - QB002 1 QB031 - QB049 1 QB051 - QB068 1 QB101 - QB110 1 QB114 - QB119 1 QB121 - QB149

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 11 of 27 **BOEING SERVICE BULLETIN 727-55-0095 Group**  **Variable Number** 1 QB151 - QB158 1 QB201 - QB220 1 QB301 - QB316 1 QB351 - QB352 1 QB401 - QB407 1 QB451 - QB458 1 QB501 - QB575 1 QB601 - QB629 1 QB651 1 QB701 - QB705 1 QB801 - QB810 1 QB901 - QB904 1 QD001 - QD012 1 QD031 - QD046 1 QD085 - QD088 1 QD101 - QD105 1 QD121 - QD127 1 QD141 - QD149 1 QD161 - QD164 1 QD191 - QD192 1 QD201 - QD239 1 QD281 - QD284 1 QD301 - QD305 1 QD321 - QD330 1 QD351 1 QD401 - QD403 1 QD407 1 QD410 1 QD421 - QD427 1 QD441 - QD453 1 QD471 - QD475 1 QD501 - QD518 1 QD551 - QD558

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 12 of 27 **BOEING SERVICE BULLETIN 727-55-0095 Group**  **Variable Number** 1 QD571 - QD572 1 QD581 - QD583 1 QD601 - QD607 1 QD621 - QD624 1 QD641 1 QD661 - QD663 1 QD681 - QD685 1 QD691 - QD692 1 QD701 - QD702 1 QD711 - QD717 1 QD741 1 QD761 - QD769 1 QD781 - QD782 1 QD791 1 QD801 - QD804 1 QD821 - QD828 1 QD901 - QD910 1 QD931 - QD932 1 QD951 - QD954 1 QD971 - QD973 1 QD991 - QD992 1 QE001 - QE002 1 QL001 - QL008 1 QL031 - QL032 1 QL081 1 QL501 - QL515 2. Spares Affected None. **B. Concurrent Requirements** None.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 13 of 27 **BOEING SERVICE BULLETIN 727-55-0095 C. Reason**  This service bulletin gives instructions to inspect the left side and right side chords of the fin closure rib for cracking or corrosion. The fin closure rib is located at the top of the vertical fin structure. The chords of the fin closure rib support the horizontal stabilizer hinge fittings. If the work in this service bulletin is not done, widespread cracking in the chords may weaken the fin closure rib structure which could result in loss of airplane control due to lack of horizontal stabilizer support. One operator reported finding a crack on the left side chord of the fin closure rib during a routine maintenance inspection. The crack measured a maximum of 2.4 inches long and it ran along the length of the chord. The airplane had accumulated 5,303 flight cycles and 11,669 flight hours when the crack was found. Cracking at this location is the result of intergranular stress corrosion caused by the material properties of 2024-T351 extrusion from which the closure rib chord is made. This material becomes vulnerable after the surface finishes begin to break down as a result of normal in-service aging. A fleet history search revealed that this occurrence is the first report of intergranular cracking of the chords. The Corrosion Prevention and Control Program (CPCP) and Maintenance Planning Data (MPD) documentation for 727 airplanes both contain visual inspections of the chords, but no NDT inspections. Accomplishment of the NDT and visual inspections in this service bulletin will make sure that any crack or corrosion in the left side or right side chords of the fin closure rib is detected. Boeing Service Related Problem (SRP) 727-SRP-55-0050 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 727 FTD 55-10001 is related to this service bulletin. **D. Description** Get access to the left side and right side chords of the fin closure rib by opening access panels at the fin closure rib. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC) inspections for any crack in the left side and right side chords. If any crack or corrosion is found, contact Boeing for repair or replacement instructions and do the work instructed by Boeing. Do repeat inspections at the interval given in Paragraph 1.E., Compliance. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 3-97 727, 727-100, 727-100C, 727- 200, 727-200F, 727C

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 14 of 27 **BOEING SERVICE BULLETIN 727-55-0095 E. Compliance**  **Table 1: Vertical Stabilizer - Fin Closure Rib Chord Inspection Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition** 

26 months. Within 24 monthsafter the original issue date of this service bulletin. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC) inspections for any crack in the left side and right side chords of the fin closurerib in accordance with Accomplishment Instructions paragraph 3.B. Part 2. All airplanes

- Before further flight. Contact Boeing for repair or replacement instructions and do the work instructed by Boeing. Any crack or corrosion found.

**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 service bulletin 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**  1.00 1.00 1 Preparation

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 15 of 27 **BOEING SERVICE BULLETIN 727-55-0095 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 1.50 1.50 1 Open Access 3.00 6.00 2 FIGURE 1 3.00 6.00 2 FIGURE 2 1.00 1.00 1 Restoration 1.50 1.50 1 Close Access 11.00 17.00 TOTAL FOR EACH AIRPLANE **H. Weight and Balance Changes** None. **I. Electrical Load Data** Not applicable. **J. References** 1. Existing Data: a. Boeing Service Related Problem (SRP) 727-SRP-55-0050 b. Standard Overhaul Practices Manual (SOPM) 20-41-05 c. 727 Aircraft Maintenance Manual (AMM) 12-30-05, 27-30-00 d. 727 Fleet Team Digest (FTD) 55-10001 e. 727 Non-Destructive Testing (NDT) Manual Part 6, 51-00-00, Figure 4, Figure 23. f. Boeing Service Letter 727-SL-51-041. 2. Data Supplied with this Service Bulletin: None. 3. Installation Drawings Used in the Preparation of this Service Bulletin: None. **K. Publications Affected** 1. Publications: None. 2. Damage Tolerance Based Structural Inspections:

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 16 of 27 **BOEING SERVICE BULLETIN 727-55-0095**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 but no new DTIs are necessary. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. **M. Software Accomplishment Summary** Not affected.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 17 of 27 **BOEING SERVICE BULLETIN 727-55-0095**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 18 of 27 **BOEING SERVICE BULLETIN 727-55-0095**

BLANK PAGE**2. MATERIAL INFORMATION A. Material - Price and Availability**  Boeing can supply the kits/parts shown in Paragraph 2.C., Parts Necessary for Each Airplane. Operators are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin. The kits/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 **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 as of the date of this**  **Service Bulletin**

**(US Dollars) ROLT as of the** **date of this Ser vice Bulletin (Cal**  **endar Days) Name**  **Number**

49,066.00

- Chord LH 65-16804-1 49,066.00

- Chord RH 65-16804-2 **B. Industry Support Information** Boeing warranty remedies are not available for the inspection procedures given in this service bulletin. **C. Parts Necessary for Each Airplane** 1. Kits/Parts None. 2. Parts and Materials Supplied by the Operator
**Notes Name**  **QTY Part Number / Speci-**  **fication** (a) Corrosion Inhibiting Compound 5 oz BMS 3-23, Type 2

- Chord LH 1 65-16804-1

- Chord RH 1 65-16804-2 (a) Refer to the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier data.
3. Parts Modified and Reidentified None.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 19 of 27 **BOEING SERVICE BULLETIN 727-55-0095**4. Parts Removed and Not Replaced None. **D. Parts Necessary to Change Spares** None. **E. Special Tooling - Price and Availability** None. **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.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 20 of 27 **BOEING SERVICE BULLETIN 727-55-0095 3. ACCOMPLISHMENT INSTRUCTIONS**  **A. GENERAL INFORMATION 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. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. 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 – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque limits to tighten nuts and bolts are in SRM Chapter 51 4. Use the approved fastener and process material substitutions in accordance with SRM Chapter 51. 5. A Detailed Inspection is defined as: An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures may be required. 6. 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. 7. Boeing Service Letter 727-SL-51-041, Damage Reporting and Repair Plan/Design Guidelines, is an acceptable procedure to request information from Boeing for additional structural repair instructions. The Service Letter describes what information must be provided to Boeing before a structural repair can be provided. 8. 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. 9. Shaded areas in Figures are reference only. Shaded areas in Figures may look different than your airplane.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 21 of 27 **BOEING SERVICE BULLETIN 727-55-0095 B. WORK INSTRUCTIONS**  1. PART 1 - PREPARATION AND ACCESS a. Place the horizontal stabilizer leading edge in the full down position. b. Position the horizontal stabilizer trim cutout switches to CUTOUT. c. Depressurize the elevator hydraulic systems A and B. Refer to 727 AMM 27-30-00 as an accepted procedure. d. Open all autopilot circuit breakers on the P18 panel and install DO-NOT-CLOSE identifiers. e. Get access to the fin upper closure rib by removing access panels 9705, 9706, 9710, 9711, 9777 and 9778. Refer to 727 AMM 12-30-05 as an accepted procedure. 2. PART 2 - INSPECTION a. Prepare the area for safe work. Refer to Part 1 as an accepted procedure. b. Do a detailed inspection for any crack or corrosion and High Frequency Eddy Current (HFEC) inspections for any crack in the left side chord of the fin closure rib in accordance with FIGURE 1. (1) If any crack or corrosion is found, do one of the options that follow: (a) Contact Boeing for replacement instructions and replace the left side chord with a new or serviceable left side chord, part number 65-16804-1, in accordance with the instructions provided by Boeing. (b) Contact Boeing for repair instructions and do the work instructed by Boeing. (2) If no cracking or corrosion is found, do repeat inspections at the interval given in Paragraph 1.E., Compliance. c. Do a detailed inspection for any crack or corrosion and HFEC inspections for any crack in the right side chord of the fin closure rib in accordance with FIGURE 2. (1) If any crack or corrosion is found, do one of the options that follow: (a) Contact Boeing for replacement instructions and replace the right side chord with a new or serviceable right side chord, part number 65-16804-2, in accordance with the instructions provided by Boeing. (b) Contact Boeing for repair instructions and do the work instructed by Boeing. (2) If no cracking or corrosion is found, do repeat inspections at the interval given in Paragraph 1.E., Compliance. d. Apply BMS 3-23, Type 2 Corrosion Inhibiting Compound to exposed areas of the fin closure rib. Refer to SOPM 20-41-05 as an accepted procedure. e. Put the airplane back to a serviceable condition. Refer to Part 3 as an accepted procedure.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 22 of 27 **BOEING SERVICE BULLETIN 727-55-0095**3. PART 3 - RESTORATION AND CLOSE ACCESS a. Close access panels 9705, 9706, 9710, 9711, 9777 and 9778. Refer to 727 AMM 12-30-05 as an accepted procedure. b. Close all autopilot circuit breakers on the P18 panel and remove DO-NOT-CLOSE identifiers. c. Pressurize the elevator hydraulic systems A and B. Refer to 727 AMM 27-30-00 as an accepted procedure. d. Position the horizontal stabilizer trim cutout switches to NORMAL. e. Put the airplane back to a serviceable condition.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 23 of 27 **BOEING SERVICE BULLETIN 727-55-0095 FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION**  **(SHEET 1 OF 2)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 24 of 27 **BOEING SERVICE BULLETIN 727-55-0095**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for one side of the airplane.
**More Data Qty**  **Identification Name**  **Task Step**  (a) 1 65-16804-1 Left Side Chord Inspect 1 (b) (f) 1 65-16804-1 Left Side Chord Inspect 2 (c) (g) 1 65-16804-1 Left Side Chord Inspect 3 (d) 1 65-16804-1 Left Side Chord Inspect 4 (e) 1 65-16804-1 Left Side Chord Inspect 5 (a) Do a detailed inspection for any crack or corrosion in the left side chord of the fin closure rib. (b) Do a detailed inspection for any crack or corrosion in the internal surfaces of the left side chord of the fin closure rib. A borescope can be used for the inspection of the internal surfaces of the chord. Access to internal surfaces can be achieved through the two access holes in the fin closure rib web. (c) Do a High Frequency Eddy Current (HFEC) transverse scan inspection for any crack in the chord lower radii in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. Access to internal surfaces canbe achieved through the two access holes in the fin closure rib web. A flexible shaft pencil probe and visual aids such as borescope and flashlight can be used as necessary to assist with the inspection of internal surfaces. At any location where the radius cannot be scanned because it is covered by structure, no HFEC inspection is required. (d) Do a HFEC parallel scan inspection for any crack in the chord upper radius in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper radius cannot be scanned because it is covered by structure, no HFEC inspection is required. (e) Do a HFEC inspection for any crack in the upper edge of the chord in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper edge cannot be scanned because it is covered by structure, no HFEC inspection is required. (f) For the borescope or video probe inspection of the forward 10 inches of the chord, it is necessary to attach a dowel rod to the borescope or video probe if a flexible borescope or video probe is used. A sleeve (tube) for the flexible borescope or video probe can be used instead of a dowel rod to make the flexible borescope or video probe rigid. (g) A 90 degree pencil probe with a minimum shaft length of 8 inches is required to reach the forward mostinspection area on the chord. Alternatively, a shorter 90 degree probe can be used with a dowel rod attached to the handle. A shorter 90 degree probe can be used for the remaining inspection areas.

**FIGURE 1: VERTICAL STABILIZER - LEFT SIDE FIN CLOSURE RIB CHORD INSPECTION (SHEET 2 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 25 of 27 **BOEING SERVICE BULLETIN 727-55-0095 FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION**  **(SHEET 1 OF 2)** Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 26 of 27 **BOEING SERVICE BULLETIN 727-55-0095**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for one side of the airplane.
**More Data Qty**  **Identification Name**  **Task Step**  (a) 1 65-16804-2 Right Side Chord Inspect 1 (b) (f) 1 65-16804-2 Right Side Chord Inspect 2 (c) (g) 1 65-16804-2 Right Side Chord Inspect 3 (d) 1 65-16804-2 Right Side Chord Inspect 4 (e) 1 65-16804-2 Right Side Chord Inspect 5 (a) Do a detailed inspection for any crack or corrosion in the right side chord of the fin closure rib. (b) Do a detailed inspection for any crack or corrosion in the internal surfaces of the right side chord of the fin closure rib. A borescope can be used for the inspection of the internal surfaces of the chord. Access to internal surfaces can be achieved through the two access holes in the fin closure rib web. (c) Do a High Frequency Eddy Current (HFEC) transverse scan inspection for any crack in the chord lower radii in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. Access to internal surfaces canbe achieved through the two access holes in the fin closure rib web. A flexible shaft pencil probe and visual aids such as borescope and flashlight can be used as necessary to assist with the inspection of internal surfaces. At any location where the radius cannot be scanned because it is covered by structure, no HFEC inspection is required. (d) Do a HFEC parallel scan inspection for any crack in the chord upper radius in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper radius cannot be scanned because it is covered by structure, no HFEC inspection is required. (e) Do a HFEC inspection for any crack in the upper edge of the chord in accordance with 727 NDT Part 6, 51-00-00, Figure 4 or Figure 23. At any location where the upper edge cannot be scanned because it is covered by structure, no HFEC inspection is required. (f) For the borescope or video probe inspection of the forward 10 inches of the chord, it is necessary to attach a dowel rod to the borescope or video probe if a flexible borescope or video probe is used. A sleeve (tube) for the flexible borescope or video probe can be used instead of a dowel rod to make the flexible borescope or video probe rigid. (g) A 90 degree pencil probe with a minimum shaft length of 8 inches is required to reach the forward mostinspection area on the chord. Alternatively, a shorter 90 degree probe can be used with a dowel rod attached to the handle. A shorter 90 degree probe can be used for the remaining inspection areas.

**FIGURE 2: VERTICAL STABILIZER - RIGHT SIDE FIN CLOSURE RIB CHORD INSPECTION (SHEET 2 OF 2)**  Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: September 24, 2012 727-55-0095 27 of 27 **BOEING SERVICE BULLETIN 727-55-0095**