# Boeing Alert Service Bulletin 727-34A0247: Revision 1 - Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2019-1072; AD 2020-06-19 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Boeing Alert Service Bulletin 727-34A0247](https://openairdocs.org/service-documents/boeing/727-34a0247.md) - Title as filed: SB 727-34A0247 R1 - Pages: 46 - PDF: https://openairdocs.org/files/sha256/6c/b9/6cb9243afb745f079388b13e99da1aa5bd314d0ec182cc484c1f0b8a7c7a0e85 - Page: https://openairdocs.org/service-documents/boeing/727-34a0247/file/6cb9243afb74 ## Text Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 Commercial Airplanes 727 Service Bulletin ALERT Number: 727-34A0247 Original Issue: January 02, 2019 Revision 1: October 01, 2019 ATA System: 3418 SUBJECT: NAVIGATION - Stall Warning System - Angle of Airflow Sensor Inspection and Replacement 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: BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2019 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 Unpublished Work.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, 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: January 02, 2019 727-34A0247Revision 1: October 01, 2019 1 of 46 3.0 ### Page 2 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 2 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT BLANK PAGE ### Page 3 Table of Contents Revision Transmittal Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1. PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 E. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 H. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . . 20 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 M. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2. MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 A. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 C. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1. Kits/Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 2. Parts and Materials Supplied by the Operator . . . . . . . . . . . . . . . . . . . . . . . . 23 3. Parts Modified and Reidentified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4. Parts Removed and Not Replaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 D. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 E. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 F. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . . . 30 3. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 FIGURE 1: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION [Group 1-4, 7] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 FIGURE 2: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION [Group 1-6] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 FIGURE 3: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER [Group 1-4, 7] . . . . . . . . . . . . . . . . . . . . . 43 FIGURE 4: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER [Group 1-6] . . . . . . . . . . . . . . . . . . . . . . . 45 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 3 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 4 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 4 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT BLANK PAGE ### Page 5 Commercial Airplanes 727 Service Bulletin ALERT Revision Transmittal SheetNumber: 727-34A0247Original Issue: January 02, 2019 Revision 1: October 01, 2019 ATA System: 3418 SUBJECT: NAVIGATION - Stall Warning System - Angle of Airflow Sensor Inspection and Replacement This revision includes all pages of the service bulletin. COMPLIANCE INFORMATION RELATED TO THIS REVISION Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2019-NM-048-AD, is related to this service bulletin. Effects of this Revision on airplanes on which Original Issue was previously done: None. Airplanes QD191 and QD192 were added to Group 1 of this service bulletin effectivity. Airplanes QB065, QD403 and QD410 were added to Group 5 of this service bulletin effectivity. Airplanes QD402 and QD407 were added to Group 6 of this service bulletin effectivity. REASON FOR REVISION This revision is sent to add airplanes to the service bulletin effectivity. These sections were changed: 1. Summary pages. COMPLIANCE, added NPRM 2019-NM-048-AD. 2. In Paragraph 1.A.1., Airplanes, changed statement and added airplanes. 3. In Paragraph 1.C., Reason, added revision statement. 4. In Paragraph 1.D., Description, added revision statement. 5. In Paragraph 1.E., Compliance, added NPRM 2019-NM-048-AD. 6. In Paragraph 1.J.1., Existing Data, updated information. 7. In Paragraph 2.C.2., Parts and Materials Supplied by the Operator, updated information. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 5 of 46 ### Page 6 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 January 02, 2019Original Issue: October 01, 2019Revision 1: Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 6 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 7 Commercial Airplanes 727 Service Bulletin ALERT SummaryNumber: 727-34A0247Original Issue: January 02, 2019 Revision 1: October 01, 2019 ATA System: 3418 SUBJECT: NAVIGATION - Stall Warning System - Angle of Airflow Sensor Inspection and Replacement THIS DOCUMENT 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 DOCUMENT TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER. CONCURRENT REQUIREMENTS None. BACKGROUND Boeing has received reports from operators of nuisance stick shaker activation while the airplane is accelerating to cruise speed at the top of a climb. A review of recorded flight data and weather reports indicated that the cause of the nuisance stick shakers was that the Angle of Airflow (AOA) sensor vanes were frozen and had become immobilized because the heaters in the AOA sensor were not sufficient to prevent ice build-up in the faceplate and vane. This can be caused during heavy moisture conditions leading to water entering the AOA vane pivot and freezing prior to or during flight. If this service bulletin is not done AOA sensors can freeze and become immobilized, which can result in no stick shaker on the affected side. If the flight crew allows the airplane to stall at low altitude, the airplane may become unrecoverable. This service bulletin gives instructions to inspect the AOA sensor(s) installed on the airplane. Also, instructions are given to replace existing AOA sensors that have heaters that are not sufficient to prevent ice build-up in the faceplate and vane. Installation of new or serviceable AOA sensor(s) prevents immobilization of the AOA sensor vane because of ice build-up. Boeing Service Related Problem (SRP) 727-SRP-34-0141 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 727 FTD 34-15001 is related to this service bulletin. Boeing Service Letter (SL) 727-SL-34-030-D is related to this service bulletin. 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 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 7 of 46 ### Page 8 ReferenceAffectedPlanning Data Paragraph 1.E., ComplianceYesAD Related Paragraph 1.H., Weight and Balance ChangesYesWeight and Balance Change Paragraph 1.I., Electrical Load DataNoElectrical Load Changed Paragraph 1.K., Publications AffectedYesPublications Affected Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew Operations Manual and/or FAA Approved Air- plane 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 NoSpecial Tooling Required ACTION Group 1-4: At STA 290.42 on the left and right side of the airplane, inspect the AOA sensors. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. Group 5-6: At STA 290.42 on the right side of the airplane, inspect the AOA sensor. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. Group 7: At STA 290.42 on the left side of the airplane, inspect the AOA sensor. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. EFFECTIVITY 727, 727-100, 727-100C, 727-200, 727-200F, 727C Airplane(s). Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplane(s). COMPLIANCE Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2019-NM-048-AD, is related to this service bulletin. Refer to Paragraph 1.E., Compliance. INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the configuration changes given in this service bulletin. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 8 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 9 MANPOWER Refer to Paragraph 1.G., Manpower. 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: January 02, 2019 727-34A0247Revision 1: October 01, 2019 9 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 10 (OCR) BOEING SERVICE BULLETIN 727-34A0247 ALERT ALERT GROUP 1-4: AT STA 290.42 ON THE LEFT AND RIGHT SIDE OF THE AIRPLANE - INSPECT THE LEFT AND RIGHT ANGLE OF AIRFLOW SENSORS - REPLACE THE ANGLE OF AIRFLOW SENSORS IF IT IS AN INCORRECT PART NUMBER GROUP 5,6: AT STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - INSPECT THE RIGHT ANGLE OF AIRFLOW SENSOR - REPLACE THE ANGLE OF AIRFLOW SENSOR IF IT IS AN INCORRECT PART NUMBER GROUP 7: AT STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - INSPECT THE LEFT ANGLE OF AIRFLOW SENSOR - REPLACE THE ANGLE OF AIRFLOW SENSOR IF IT IS AN INCORRECT PART NUMBER ANGLE OF AIRFLOW SENSOR 2848470 (RIGHT SIDE SHOWN, LEFT SIDE OPPOSITE) Original Issue: January 02, 2019 Revision 1: October 01, 2019 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 727-34A0247 Work - See page 1 for details. 10 of 46 ### Page 11 Commercial Airplanes 727 Service Bulletin ALERT Number: 727-34A0247 Original Issue: January 02, 2019 Revision 1: October 01, 2019 ATA System: 3418 SUBJECT: NAVIGATION - Stall Warning System - Angle of Airflow Sensor Inspection and Replacement THIS DOCUMENT 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 DOCUMENT TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER. 1. PLANNING INFORMATION A. Effectivity 1. Airplanes This bulletin is applicable to 727, 727-100, 727-100C, 727-200, 727-200F, 727C Airplane(s), line number(s) 1-1832 in 7 Group(s). Where the effectivity is presented with hyphens between line numbers, the airplane applicability means "through" and "inclusive", e.g. line numbers 1-9 means line numbers 1 through 9 inclusive. Refer to Service Bulletin Index D6-9825 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. The Variable Numbers and Group Information for the applicable airplanes is given below. DESCRIPTIONCONFIGURATIONGROUP Airplanes with Angle of Airflow sensors installed on the left and right side of the airplane that must be part number 2566A-21 or 2566A-30. -1 Airplanes with Angle of Airflow sensors installed on the left side of the airplane that must be part number 2566A-21 or 2566A-30 and on the right side of the airplane that must be part number 2566A-30. -2 Airplanes with Angle of Airflow sensors installed on the left side of the airplane that must be part number 2566A-30 and on the right side of the airplane that must be part number 2566A-21 or 2566A-30. -3 Airplanes with Angle of Airflow sensors installed on the left and right side of the airplane that must be part number 2566A-30. -4 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 11 of 46 ### Page 12 DESCRIPTIONCONFIGURATIONGROUP Airplanes with an Angle of Airflow sensor installed on the right side of the airplane that must be part number 2566A-21 or 2566A-30. -5 Airplanes with an Angle of Airflow sensor installed on the right side of the airplane that must be part number 2566A-30. -6 Airplanes with an Angle of Airflow sensor installed on the left side of the airplane that must be part number 2566A-21 or 2566A-30. -7 Airplane Models: 727, 727-100, 727-100C, 727-200, 727-200F, 727C GroupVariable Number 1E0001 - E0042 2E0101 - E0140 2E0201 - E0213 1E0214 - E0216 1E0301 - E0351 1E0401 - E0423 2E3001 - E3006 2E3011 - E3014 2E3021 - E3040 2E3059 2E3061 - E3077 2E3101 - E3103 2E3111 - E3118 2E3141 - E3143 4E3144 - E3147 2E3148 4E3149 2E3150 - E3152 2E3171 - E3177 2E3201 - E3206 2E3221 - E3224 2E3241 - E3290 GroupVariable Number 2E3341 - E3350 2E3401 - E3421 2E3451 - E3452 2E3471 - E3474 2E3501 - E3513 2E3516 - E3523 2E3551 - E3553 1E3571 - E3578 2E3601 - E3604 2E3621 - E3622 2E3651 - E3655 2E3677 2E3681 - E3684 2E3701 - E3704 2E3751 - E3755 2E3781 - E3784 2E5001 - E5011 2E5031 - E5068 2E5101 - E5116 2E5141 - E5143 2E5161 - E5164 2E5201 - E5203 GroupVariable Number 2E5221 - E5245 2E5251 - E5252 2E5271 - E5281 2E5301 - E5306 2E5351 - E5353 2E5381 - E5382 2E5401 - E5424 2E5426 - E5429 2E5433 2E5435 2E5451 - E5455 2E5481 - E5483 2E5501 - E5502 5QA001 - QA018 6QA019 - QA021 5QA022 - QA046 5QA051 - QA099 5QA101 - QA196 6QA197 5QA198 - QA199 5QA201 - QA225 5QA301 - QA349 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 12 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 13 GroupVariable Number 5QA351 - QA376 5QA378 2QA401 - QA499 5QA501 - QA537 5QA551 - QA579 5QA581 - QA585 6QA601 - QA688 6QA701 - QA753 5QA801 - QA805 5QA851 - QA899 5QA901 - QA946 5QA949 6QB001 - QB002 5QB031 - QB049 5QB051 - QB068 5QB101 - QB110 5QB114 - QB119 6QB121 - QB149 6QB151 - QB158 5QB201 - QB220 5QB301 - QB316 5QB351 - QB352 5QB401 - QB407 5QB451 - QB458 5QB501 - QB575 5QB601 - QB629 5QB651 2QB701 - QB705 GroupVariable Number 5QB801 - QB810 5QB901 - QB904 6QD001 - QD012 3QD031 - QD040 4QD041 - QD042 6QD043 - QD046 5QD085 - QD088 5QD101 - QD105 5QD121 - QD127 6QD141 - QD149 6QD161 - QD164 1QD191 - QD192 5QD201 - QD239 5QD281 - QD284 5QD301 - QD305 6QD321 - QD330 5QD351 6QD401 - QD402 5QD403 6QD407 5QD410 7QD421 - QD427 6QD441 - QD453 5QD471 - QD475 5QD501 - QD518 5QD551 - QD554 6QD555 - QD558 6QD571 - QD572 GroupVariable Number 5QD581 - QD583 5QD601 - QD607 5QD621 - QD624 5QD641 6QD661 - QD663 6QD681 - QD685 6QD691 - QD692 5QD701 - QD702 6QD711 - QD717 5QD741 6QD761 - QD769 6QD781 - QD782 6QD791 2QD801 - QD804 6QD821 - QD828 1QD901 - QD910 5QD931 - QD932 6QD951 - QD954 6QD971 - QD973 5QD991 - QD992 5QE001 6QE002 5QL001 - QL008 5QL031 - QL032 6QL081 6QL501 - 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: January 02, 2019 727-34A0247Revision 1: October 01, 2019 13 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 14 C. Reason Boeing has received reports from operators of nuisance stick shaker activation while the airplane is accelerating to cruise speed at the top of a climb. A review of recorded flight data and weather reports indicated that the cause of the nuisance stick shakers was that the Angle of Airflow (AOA) sensor vanes were frozen and had become immobilized because the heaters in the AOA sensor were not sufficient to prevent ice build-up in the faceplate and vane. This can be caused during heavy moisture conditions leading to water entering the AOA vane pivot and freezing prior to or during flight. If this service bulletin is not done AOA sensors can freeze and become immobilized, which can result in no stick shaker on the affected side. If the flight crew allows the airplane to stall at low altitude, the airplane may become unrecoverable. This service bulletin gives instructions to inspect the AOA sensor(s) installed on the airplane. Also, instructions are given to replace existing AOA sensors that have heaters that are not sufficient to prevent ice build-up in the faceplate and vane. Installation of new or serviceable AOA sensor(s) prevents immobilization of the AOA sensor vane because of ice build-up. Boeing Service Related Problem (SRP) 727-SRP-34-0141 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 727 FTD 34-15001 is related to this service bulletin. Boeing Service Letter (SL) 727-SL-34-030-D is related to this service bulletin. Revision 1 is sent to add airplanes to the service bulletin effectivity. D. Description Group 1-4: At STA 290.42 on the left and right side of the airplane, inspect the AOA sensors. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. Group 5-6: At STA 290.42 on the right side of the airplane, inspect the AOA sensor. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. Group 7: At STA 290.42 on the left side of the airplane, inspect the AOA sensor. If an AOA sensor has an incorrect part number, replace it with a new or serviceable AOA sensor. If an AOA sensor has a correct part number, no AOA sensor replacement is required. Effects of this Revision on airplanes on which Original Issue was previously done: None. The work in this service bulletin is done in the maintenance zone(s) given below. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 14 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 15 Group 1, 4: Affected Maintenance Zones ZoneModel 2-21, 2-22727, 727-200 Group 2: Affected Maintenance Zones ZoneModel 2-21, 2-22727, 727-100, 727-100C, 727- 200, 727C Group 3, 5, 7: Affected Maintenance Zones ZoneModel 2-21, 2-22727-200 Group 6: Affected Maintenance Zones ZoneModel 2-21, 2-22727-200, 727-200F E. Compliance Federal Aviation Administration (FAA) Notice of Proposed Rule Making NPRM 2019-NM-048-AD, is related to this service bulletin. When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When more than one ACTION is given for a CONDITION or an OPTION, do all of the ACTION numbers for that CONDITION or OPTION. Accomplish the required action(s), based on the applicable condition(s) in Table(s) 1, in accordance with Paragraph 3. Accomplishment Instructions. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 15 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 16 Table 1: ANGLE OF AIRFLOW SENSOR INSPECTION Repeat Interval (Not to Exceed) Compliance TimeActionCondition -Within 2,750 flight hours after the original issue date of this service bul- letin. OPTION 1: Do a General Visual Inspection of the Angle of Airflow sensor on the airplane. All Airplanes OPTION 2: Inspection for the Angle of Airflow sen- sor not on airplane. -Before further flight. Replace the affected An- gle of Airflow sensor. CONDITION 1: OPTION 1: ANY ANGLE OF AIRFLOW SENSOR WITH A SWEPT BACK SHAPE VANE FOUND --No further action is re- quired. CONDITION 2: OPTION 1: ANY ANGLE OF AIRFLOW SENSOR WITH A RECT- ANGULAR FLAG SHAPE VANE FOUND -Before further flight. Replace the affected An- gle of Airflow sensor. CONDITION 3: OPTION 2: ANY ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOE- ING PART NUMBER 10- 62047-1) FOUND --No further action is re- quired. CONDITION 4: OPTION 2: NO ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOE- ING PART NUMBER 10- 62047-1) 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. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 16 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 17 G. Manpower The table below shows an estimate of the task hours necessary to do this change 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 Group 1-4: OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 0.050.051FIGURE 1 0.050.051FIGURE 2 1.001.001Remove (a) 1.001.001Install (a) 0.250.251Test (a) 0.100.101Close Access 2.552.55TOTAL FOR EACH AIRPLANE (a) Removal, installation and test are dependent on inspection results. This esti- mate includes the hours necessary for the removal, installation and test of both left and right AOA sensors. Group 1-4: OPTION 2: INSPECTION WITH THE ANGLE OF ATTACK SENSOR NOT ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 1.001.001Remove 0.050.051FIGURE 3 0.050.051FIGURE 4 1.001.001Install 0.250.251Test 0.100.101Close Access Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 17 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 18 Group 1-4: OPTION 2: INSPECTION WITH THE ANGLE OF ATTACK SENSOR NOT ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 2.552.55TOTAL FOR EACH AIRPLANE Group 5-6: OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 0.050.051FIGURE 2 0.500.501Remove (a) 0.500.501Install (a) 0.250.251Test (a) 0.100.101Close Access 1.501.50TOTAL FOR EACH AIRPLANE (a) Removal, installation and test are dependent on inspection results. Group 5-6: OPTION 2: INSPECTION WITH THE ANGLE OF ATTACK SENSOR NOT ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 0.500.501Remove 0.050.051FIGURE 4 0.500.501Install 0.250.251Test 0.100.101Close Access 1.501.50TOTAL FOR EACH AIRPLANE Group 7: OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 0.050.051FIGURE 1 0.500.501Remove (a) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 18 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 19 Group 7: OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.500.501Install (a) 0.250.251Test (a) 0.100.101Close Access 1.501.50TOTAL FOR EACH AIRPLANE (a) Removal, installation and test are dependent on inspection results. Group 7: OPTION 2: INSPECTION WITH THE ANGLE OF ATTACK SENSOR NOT ON AIRPLANE Elapsed HoursTask HoursNumber of PersonsTask 0.100.101Open Access 0.500.501Remove 0.050.051FIGURE 3 0.500.501Install 0.250.251Test 0.100.101Close Access 1.501.50TOTAL FOR EACH AIRPLANE H. Weight and Balance Changes Change in Moment (Pound-Inches)Change in Weight (Pounds)Airplane -199.5-0.7727, 727-100, 727-100C (a)(b) (a) Applicable to the installation of AOA sensor part number 2566A-21. (b) This is the weight change for the replacement of one AOA sensor. Inspection results will determine the quantity needed. Change in Moment (Pound-Inches)Change in Weight (Pounds)Airplane -156.8-0.5727, 727-100, 727-100C (a)(b) (a) Applicable to the installation of AOA sensor part number 2566A-30. (b) This is the weight change for the replacement of one AOA sensor. Inspection results will determine the quantity needed. Change in Moment (Pound-Inches)Change in Weight (Pounds)Airplane -117.1-0.7727-200, 727-200F (a)(b) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 19 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 20 Change in Moment (Pound-Inches)Change in Weight (Pounds)Airplane (a) Applicable to the installation of AOA sensor part number 2566A-21. (b) This is the weight change for the replacement of one AOA sensor. Inspection results will determine the quantity needed. Change in Moment (Pound-Inches)Change in Weight (Pounds)Airplane -92.0-0.5727-200, 727-200F (a)(b) (a) Applicable to the installation of AOA sensor part number 2566A-30. (b) This is the weight change for the replacement of one AOA sensor. Inspection results will determine the quantity needed. I. Electrical Load Data Not applicable. J. References 1. Existing Data: a. Boeing Service Letter 727-SL-34-030-D b. Boeing Service Related Problem (SRP) 727-SRP-34-0141 c. Federal Aviation Administration (FAA) Notice of Proposed Rule Making (NPRM) 2019-NM-048-AD d. Service Bulletin Index D6-9825 e. 727 Aircraft Maintenance Manual (AMM) 34-18-01, 34-18-51 f. 727 Fleet Team Digest (FTD) 34-15001 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: Chapter-SectionPublication 34-10727 Illustrated Parts Catalog 2. Damage Tolerance Based Structural Inspections: Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 20 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 21 Boeing has evaluated the repairs 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 does not affect FCS, therefore DTIs are not necessary. L. Interchangeability and Intermixability of Parts Refer to Paragraph 2.C., Parts Necessary for Each Airplane, for interchangeability and intermixability information. M. Software Accomplishment Summary Not affected. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 21 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 22 Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 22 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT BLANK PAGE ### Page 23 2. MATERIAL INFORMATION A. Material - Price and Availability The operator can supply the parts and materials shown in Paragraph 2.C., Parts Necessary for Each Airplane. As an alternative, operators can purchase the parts from Boeing Spares. This service bulletin does not show the Boeing price and supply data. B. Industry Support Information Boeing warranty remedies are not available for the configuration changes given in this service bulletin. C. Parts Necessary for Each Airplane 1. Kits/Parts None. 2. Parts and Materials Supplied by the Operator The following parts or materials are necessary to do the change in this service bulletin. Parts and materials in the manuals given in Paragraph 1.J., References, can also be necessary. Examine operator part and material supply to make sure all necessary parts and materials are available. Group 1: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (a)(b)(c)10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 210-60878-3 OR 10-60878- 4 2566A-21 OR 2566A-30 (d)66-21153-4-GASKET266-21153-4- (d)66-21153-6-GASKET466-21153-6- (d)66-21153-7 (66-21153-8 optional) -FILLER RING266-21153-7 (66-21153-8 optional) - (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 23 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 24 Group 1: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts,Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. Group 2: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number Left side of airplane (a)(b)(c) 10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-3 OR 10-60878- 4 2566A-21 OR 2566A-30 Right side of airplane (a)(b)(c) 10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-42566A-30 (d)66-21153-4-GASKET266-21153-4- (d)66-21153-6-GASKET466-21153-6- (d)66-21153-7 (66-21153-8 optional) -FILLER RING266-21153-7 (66-21153-8 optional) - Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 24 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 25 Group 2: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts,Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. Group 3: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number Left side of airplane (a)(b)(c) 10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-42566A-30 Right side of airplane (a)(b)(c) 10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-3 OR 10-60878- 4 2566A-21 OR 2566A-30 (d)66-21153-4-GASKET266-21153-4- (d)66-21153-6-GASKET466-21153-6- Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 25 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 26 Group 3: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (d)66-21153-7 (66-21153-8 optional) -FILLER RING266-21153-7 (66-21153-8 optional) - (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts,Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. Group 4: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (a)(b)(c)10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 210-60878-42566A-30 (d)66-21153-4-GASKET266-21153-4- (d)66-21153-6-GASKET466-21153-6- Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 26 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 27 Group 4: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (d)66-21153-7 (66-21153-8 optional) -FILLER RING266-21153-7 (66-21153-8 optional) - (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts,Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. Group 5, 7: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (a)(b)(c)10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-3 OR 10-60878- 4 2566A-21 OR 2566A-30 (d)66-21153-4-GASKET166-21153-4- (d)66-21153-6-GASKET266-21153-6- Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 27 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 28 Group 5, 7: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (d)66-21153-7 (66-21153-8 optional) -FILLER RING166-21153-7 (66-21153-8 optional) - (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts,Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. Group 6: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (a)(b)(c)10-62047-10861CAKSENSOR - ANGLE OF AIRFLOW 110-60878-42566A-30 (d)66-21153-4-GASKET166-21153-4- (d)66-21153-6-GASKET266-21153-6- Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 28 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 29 Group 6: NotesExisting Boe- ing Part Num- ber Existing Sup- plier Part Number NameQTYNew Boeing Part Number New Supplier Part Number (d)66-21153-7 (66-21153-8 optional) -FILLER RING166-21153-7 (66-21153-8 optional) - (a) The quantity shown is the maximum quantity of AOA sensors installed on one airplane. Inspection results will determine quantity needed. (b) You cannot use the existing part to replace the new part. (c) Supplier Information: GECAS Materials (0007), CAGE: 7421. Tel: 901-362-8600, Fax: 901-365-1482, Email: Sales@gecas.com Aero Controls, Inc. (0062). Tel: 253-269-3100, Fax: 253-269-6700, Email: sales@aerocontrols.com Kellstrom Aerospace (0096), CAGE: 57187. Tel: 847-233-5800, Fax: 847-233-5900, Email: William.Braun@kellstromaerospace.com Resources, Int'L (5018). Tel: 480-961-3600, Email: RFQ@TurboResources.com Unical Aviation Inc. (9420). Tel: 909-348-1700, Fax: 909-869-7685, Email: sales@unical.com Velocity Aerospace - NMB (AMSD). Tel: 214-396-9040, Email: NMBSales@VelocityAerospace.com AvAir (AT39). Tel: 480-496-6736, Email: sales@avair.aero OH Capital Assets, Inc. (B4XA). Tel: 704-283-5080, Fax: 704-283-5372, Email: info@ohcapitalassets.com Dodson International Parts, Inc (3581). Tel: 785-878-8000, Fax: 785-878-8800, Email: sales@dodson.com European Aviation Ltd / Skybus (A0V9). Tel 44 1531 633000, Email: jane.taylor@euroav.com (d) The quantity shown is the maximum quantity required. A new gasket is required every time the AOA sensor is removed and installed. Refer to 727 AMM 34-18-51 Angle of Airflow Sensor Installation to de- termine the parts required and quantity needed. 3. Parts Modified and Reidentified None. 4. Parts Removed and Not Replaced None. D. Parts Necessary to Change Spares None. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 29 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 30 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: January 02, 2019 727-34A0247Revision 1: October 01, 2019 30 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 31 3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION 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. CAUTION 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 – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque Values: — Values for structural fasteners are given in 727 Structural Repair Manual, Chapter 51. — Values for airframe maintenance tasks are included in Chapter 20 of 727 Aircraft Maintenance Manual (AMM). — Values for electrical maintenance tasks are included in Chapter 20 of Standard Wiring Practices Manual (SWPM). — Values for engine maintenance tasks are included in Chapter 70 of 727 Aircraft Maintenance Manual (AMM). — Non-standard torque values for maintenance tasks are included in the applicable installation step. 4. A General Visual Inspection is defined as: A visual examination of an interior or exterior area, installation or assembly to detect obvious damage, failure or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight or drop-light and may require removal or opening of access panels or doors. Stands, ladders or platforms may be required to gain proximity to the area being checked. 5. 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. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 31 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 32 6. 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. 7. 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. 8. 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. 9. Use of colors in Figures is based on guidance from the ATA e-Business Program (ATA) iSpec 2200. 10. When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When more than one ACTION is given for a CONDITION or an OPTION, do all of the ACTION numbers for that CONDITION or OPTION. 11. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS are in Paragraph 1.E., Compliance. 12. Some steps in the Work Instructions are labeled as Required for Compliance (RC). If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps labeled as RC, including sub-steps under an RC step and any figures identified in an RC step, must be done to comply with the AD. If a step or sub-step is labeled "RC Exempt," then the RC requirement is removed from that step or sub-step. An Alternative Method of Compliance (AMOC) is required for any deviations to RC steps, including sub-steps and identified figures. Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC. This is provided that the RC steps, including sub-steps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. B. WORK INSTRUCTIONS 1. Group 1-4: Get access to the Angle of Airflow (AOA) sensors at STA 290.42 on the left and right side of the airplane. 2. Group 5-6: Get access to the Angle of Airflow (AOA) sensor at STA 290.42 on the right side of the airplane. 3. Group 7: Get access to the Angle of Airflow (AOA) sensor at STA 290.42 on the left side of the airplane. 4. Group 1-4: RC - Do one of the options that follow: a. OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE (1) Do a GVI of the AOA sensors in accordance with FIGURE 1 and FIGURE 2. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 32 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 33 (a) CONDITION 1: ANY ANGLE OF AIRFLOW SENSOR WITH A SWEPT BACK SHAPE VANE FOUND 1) Remove the affected AOA sensor. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) Group 1: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 3) Group 2: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 4) Group 3: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 5) Group 4: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 6) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 33 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 34 (b) CONDITION 2: ANY ANGLE OF AIRFLOW SENSOR WITH A RECTANGULAR FLAG SHAPE VANE FOUND 1) No further action is required. b. OPTION 2: INSPECTION WITH THE ANGLE OF AIRFLOW SENSOR NOT ON AIRPLANE (1) On the left and right side of the airplane remove the AOA sensors. Refer to 727 AMM 34-18-51 as an accepted procedure. (2) Do a GVI of the AOA sensors for the part number in accordance with FIGURE 3 and FIGURE 4. (a) CONDITION 3: ANY ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Group 1: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 2) Group 2: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 3) Group 3: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. b) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 4) Group 4: Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 34 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 35 b) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 5) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. (b) CONDITION 4: NO ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Install the existing part back on the airplane. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. 5. Group 5-6: RC - Do one of the options that follow: a. OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE (1) Do a GVI of the AOA sensor in accordance with FIGURE 2. (a) CONDITION 1: ANY ANGLE OF AIRFLOW SENSOR WITH A SWEPT BACK SHAPE VANE FOUND 1) Remove the affected AOA sensor. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) Group 5: Install a new or serviceable AOA sensor as follows: a) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 3) Group 6: Install a new or serviceable AOA sensor as follows: a) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 4) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 35 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 36 (b) CONDITION 2: ANY ANGLE OF AIRFLOW SENSOR WITH A RECTANGULAR FLAG SHAPE VANE FOUND 1) No further action is required. b. OPTION 2: INSPECTION WITH THE ANGLE OF AIRFLOW SENSOR NOT ON AIRPLANE (1) On the right side of the airplane remove the AOA sensor. Refer to 727 AMM 34-18-51 as an accepted procedure. (2) Do a GVI of the AOA sensor for the part number in accordance with FIGURE 4. (a) CONDITION 3: ANY ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Group 5: Install a new or serviceable AOA sensor as follows: a) On the right side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 2) Group 6: Install a new or serviceable AOA sensor as follows: a) On the right side of the airplane install part number 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 3) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. (b) CONDITION 4: NO ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Install the existing part back on the airplane. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. 6. Group 7: RC - Do one of the options that follow: a. OPTION 1: GENERAL VISUAL INSPECTION (GVI) OF THE ANGLE OF AIRFLOW SENSOR ON AIRPLANE (1) Do a GVI of the AOA sensor in accordance with FIGURE 1. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 36 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 37 (a) CONDITION 1: ANY ANGLE OF AIRFLOW SENSOR WITH A SWEPT BACK SHAPE VANE FOUND 1) Remove the affected AOA sensor. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 3) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. (b) CONDITION 2: ANY ANGLE OF AIRFLOW SENSOR WITH A RECTANGULAR FLAG SHAPE VANE FOUND 1) No further action is required. b. OPTION 2: INSPECTION WITH THE ANGLE OF AIRFLOW SENSOR NOT ON AIRPLANE (1) On the left side of the airplane remove the AOA sensor. Refer to 727 AMM 34-18-51 as an accepted procedure. (2) Do a GVI of the AOA sensor for the part number in accordance with FIGURE 3. (a) CONDITION 3: ANY ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Install a new or serviceable AOA sensor as follows: a) On the left side of the airplane install part number 2566A-21 (Boeing part number 10-60878-3) or 2566A-30 (Boeing part number 10-60878-4). Refer to 727 AMM 34-18-51 as an accepted procedure. 2) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. (b) CONDITION 4: NO ANGLE OF AIRFLOW SENSOR WITH PART NUMBER 861CAK (BOEING PART NUMBER 10-62047-1) FOUND 1) Install the existing part back on the airplane. Refer to 727 AMM 34-18-51 as an accepted procedure. 2) RC Exempt - Do the Operational Test of the Stall Warning System. If the test fails, accomplish corrective actions and repeat the test and applicable corrective actions until the test is passed. Refer to 727 AMM 34-18-01 as an accepted procedure. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 37 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 38 7. Put the airplane back to a serviceable condition. Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1: October 01, 2019 38 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 39 This Figure applies only to: Group 1-4, 7. FIGURE 1: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 39 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 40 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 each airplane. More DataQtyIdentificationNameTaskStep (a)1-SENSOR - ANGLE OF AIRFLOW Inspect1 (a) Do a general visual inspection of the AOA sensor's vane to determine if the vane is a swept back or rectangular flag shape vane. FIGURE 1: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 40 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 41 This Figure applies only to: Group 1-6. FIGURE 2: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION (SHEET 1 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 41 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 42 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 each airplane. More DataQtyIdentificationNameTaskStep (a)1-SENSOR - ANGLE OF AIRFLOW Inspect1 (a) Do a general visual inspection of the AOA sensor's vane to determine if the vane is a swept back or rectangular flag shape vane. FIGURE 2: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - VANE INSPECTION (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 42 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 43 (OCR) BOEING SERVICE BULLETIN 727-34A0247 ALERT ALERT This Figure applies only to: Group 1-4, 7. OR B 2848589 FIGURE 3: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER (SHEET 1 OF 2) Original Issue: January 02, 2019 Revision 1 October 01, 2019 PROPRIETARY - Copyright © Unpublished Export Controlled ECCN: 9E991 - BOEING 727-34A0247 Work - See page 1 for details. 43 of 46 ### Page 44 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 each airplane. More DataQtyIdentificationNameTaskStep Inspect for part number. 1-SENSOR - ANGLE OF AIRFLOW Inspect1 FIGURE 3: STA 290.42 ON THE LEFT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 44 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT ### Page 45 (OCR) BOEING SERVICE BULLETIN 727-34A0247 ALERT ALERT This Figure applies only to: Group 1-6. 2848590 FIGURE 4: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER (SHEET 1 OF 2) Original Issue: January 02, 2019 Revision 1 October 01, 2019 Export Controlled ECCN: 9E991 - BOEING 727-34A0247 PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 45 of 46 ### Page 46 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 each airplane. More DataQtyIdentificationNameTaskStep Inspect for part number. 1-SENSOR - ANGLE OF AIRFLOW Inspect1 FIGURE 4: STA 290.42 ON THE RIGHT SIDE OF THE AIRPLANE - ANGLE OF AIRFLOW SENSOR - INSPECTION FOR PART NUMBER (SHEET 2 OF 2) Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: January 02, 2019 727-34A0247Revision 1 October 01, 2019 46 of 46 BOEING SERVICE BULLETIN 727-34A0247 ALERTALERT --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.