### Commercial **Airplanes** 

# 757 Service Bulletin **ALERT Number: 757-27A0145**  Original Issue: August 07, 2003 Revision 1: January 20, 2010 ATA System: 2741 **SUBJECT:** FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator - Ballscrew Freeplay Inspection Addition and Lubrication Interval Change Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 730-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2003 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work. This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 1 of 27 2.0BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 2 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

BLANK PAGE**Table of Contents** Revision Transmittal Sheet............................................ 5 Summary...................................................... 7 1. PLANNING INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 B. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 C. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 D. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 I. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 J. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 19 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 L. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 B. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 C. Parts Necessary For Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2. Parts and Materials Supplied by the Operator:. . . . . . . . . . . . . . . . . . . . . . . . 21 3. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4. Parts Removed and Not Replaced:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 21 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 A. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 FIGURE 1: INSPECTION OF HORIZONTAL STABILIZER BALLSCREW LOAD PATH . . . . . . . . 25 FIGURE 2: HORIZONTAL STABILIZER BALLSCREW AND BALLNUT FREEPLAY CHECK. . . . . 26 FIGURE 3: HORIZONTAL STABILIZER TRIM BALLSCREW ACTUATOR REPLACEMENT . . . . . 27

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 3 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 4 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

BLANK PAGE

### Commercial **Airplanes** 

# 757 Service Bulletin **ALERT Revision Transmittal Sheet**  **Number: 757-27A0145** Original Issue: August 07, 2003 Revision 1: January 20, 2010 ATA System: 2741 **SUBJECT:** FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator - Ballscrew Freeplay Inspection Addition and Lubrication Interval Change This Revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** No more work is necessary on airplanes changed as shown in the original issue of this service bulletin. However, operators must continue with the repeat inspections, lubrication and freeplay checks in accordance with Paragraph 1.E., Compliance. **REASON FOR REVISION** This revision is sent to change the compliance times of the detailed inspection, lubrication and ballnut-to-ballscrew freeplay check. Instructions on how to accomplish the detailed inspection are replaced by an instruction to do the detailed inspection in accordance with the Aircraft Maintenance Manual (AMM) and Part 3 is added to the work instructions to give lubrication instructions. This revision also adds an Airworthiness Directive (AD) statement and removes all figures as the procedures are now accomplished by the AMM. These sections are changed: 1. Summary: – Background: A interim notification of a revision to the Maintenance Planning Document (MPD) statement is removed. – Action: The statement is updated to agree with the updated work instructions. – Compliance: An Airworthiness Directive (AD) statement is added. – Manpower: The manpower table is removed. – Illustration: The summary illustration paragraph is updated. 2. Planning Information: – Paragraph 1.A., Effectivity: A group configuration table is added which splits the effectivity into 3 configurations. – Paragraph 1.C., Reason: A interim notification of a revision to the Maintenance Planning Document (MPD) statement is removed. – Paragraph 1.D., Description: The statement is updated to agree with the updated work instructions and maintenance zones are added. – Paragraph 1.E., Compliance: An Airworthiness Directive (AD) statement is added.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 5 of 27– Paragraph 1.E., Compliance: The compliance times and the repeat intervals for the detailed inspection, lubrication and freeplay check in Tables 1 and 2 are changed. The corrective action for damaged parts is added, footnotes (a) and (b) are changed and footnote (c) is deleted. – Paragraph 1.E., Compliance: The compliance times and the repeat intervals for the detailed inspection, lubrication and freeplay check in Table 3 are changed. The corrective action for damaged parts is added, footnotes (a) and (b) are changed and footnotes (c) and (d) are deleted. – Paragraph 1.G., Manpower: The manpower table is updated. 3. Accomplishment Instructions: – Paragraph 3.B., Work Instructions: A note is removed from Part 1, Step 1 and the access, cleaning, lubrication and detailed inspection instructions are replaced by one instruction to do a detailed inspection in accordance with the AMM. – Paragraph 3.B., Work Instructions: The access instruction is removed from Part 2 and an AMM task is added to the instruction to do the stabilizer ballscrew to ballnut freeplay check. – Paragraph 3.B., Work Instructions: Part 3 is added to give lubrication instructions. – Figure 1: This Figure is deleted. – Figure 2: This Figure is deleted. – Figure 3: This Figure is deleted. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes. **REVISION HISTORY** August 07, 2003 Original Issue: January 20, 2010 Revision 1:

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 6 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 757 Service Bulletin **ALERT Summary**  **Number: 757-27A0145** Original Issue: August 07, 2003 Revision 1: January 20, 2010 ATA System: 2741 **SUBJECT:** FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator - Ballscrew Freeplay Inspection Addition and Lubrication Interval Change
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. **CONCURRENT REQUIREMENTS**
None. **BACKGROUND** This service bulletin is being issued to provide a new stabilizer ballscrew lubrication interval and detailed inspection interval. Also, a new stabilizer ballscrew to ballnut freeplay check is included with a recommended check interval. The inspections/check are an added level of protection which reduces the potential of unlikely failure modes of the stabilizer ballscrew assembly used on the stabilizer actuator. The inspections/check can be run in-situ on the airplane. After an MD-80 horizontal stabilizer jackscrew incident, a design review was initiated of the Boeing heritage horizontal stabilizer ballscrews. During this review, an operator reported a 757 horizontal stabilizer ballscrew with extensive corrosion. An investigation was initiated. This investigation identified that a maintenance procedure to check the stabilizer ballscrew primary load path was required. Loss of the horizontal stabilizer ballscrew primary and secondary load paths, although extremely improbable, could potentially result in the loss of control of the airplane. Boeing Service Related Problem (SRP) 757-SRP-27-0153 is related to this service bulletin.
**NOTE:** Service Bulletin 757-27-0138 served as an interim maintenance action related to 757-SRP-27-0153. Service Bulletin 757-27A0145 is the final maintenance recommendation related to 757-SRP-27-0153. Upon release of Service Bulletin 757-27A0145, operators should perform the maintenance actions in that bulletin rather than those in Service Bulletin 757-27-0138. However, it should be noted that Service Bulletin 757-27-0138 includes one maintenance action that is not included in Service Bulletin 757-27A0145: lubrication of the stabilizer pivot hinges. Lubrication of the stabilizer pivot hinges was included in Service Bulletin 757-27-0138 as a convenience; it is unrelated to the safety issue addressed in safety 757-SRP-27-0153. Boeing recommends that operators continue to perform the stabilizer hinge lubrication task per 757 MPD Volume 1 Section 5, and 757 AMM 12-21-05.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 7 of 27**ACTION** Get access to the horizontal stabilizer trim ballscrew actuator and do the procedures that follow below at the intervals shown in Paragraph 1.E., Compliance: – Do a detailed inspection of the stabilizer ballscrew assembly. – Lubricate the horizontal stabilizer trim control system. – Do a stabilizer ballscrew to ballnut freeplay check. – Replace damaged and/or cracked and/or worn stabilizer trim ballscrew actuators. **EFFECTIVITY** All 757-300 Airplanes. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes. **COMPLIANCE** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Refer to Paragraph 1.E., Compliance. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the tasks given in this service bulletin. **MANPOWER** Refer to Paragraph 1.G., Manpower.
**MATERIAL INFORMATION** Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 8 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 9 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 10 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

BLANK PAGE

### Commercial **Airplanes** 

# 757 Service Bulletin **ALERT Number: 757-27A0145**  Original Issue: August 07, 2003 Revision 1: January 20, 2010 ATA System: 2741 **SUBJECT:** FLIGHT CONTROLS - Horizontal Stabilizer - Horizontal Stabilizer Trim Actuator - Ballscrew Freeplay Inspection Addition and Lubrication Interval Change
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER.
**1. PLANNING INFORMATION A. Effectivity**  1. Airplanes Refer to Service Bulletin Index Document D624N001 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below.
**DESCRIPTION CONFIGURATION**  **GROUP** All 757-300 airplanes.

- 1 Airplanes that have not done an overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have less than or equal to 15,000 total flight hours. 1

Airplanes that have not done an overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have more than 15,000 total flight hours. 2

Airplanes that have done an overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143. 3

Airplane Models:
757-300

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 11 of 27**Group Variable Number**  1 NL001 - NL002 1 NL006 - NL017 1 NL101 - NL109 1 NL141 1 NL601 - NL616 1 NU701 - NU705 1 NU721 - NU728 1 NU731 - NU732 2. Spares Affected
None. **B. Concurrent Requirements**
None. **C. Reason** This service bulletin is being issued to provide a new stabilizer ballscrew lubrication interval and detailed inspection interval. Also, a new stabilizer ballscrew to ballnut freeplay check is included with a recommended check interval. The inspections/check are an added level of protection which reduces the potential of unlikely failure modes of the stabilizer ballscrew assembly used on the stabilizer actuator. The inspections/check can be run in-situ on the airplane. After an MD-80 horizontal stabilizer jackscrew incident, a design review was initiated of the Boeing heritage horizontal stabilizer ballscrews. During this review, an operator reported a 757 horizontal stabilizer ballscrew with extensive corrosion. An investigation was initiated. This investigation identified that a maintenance procedure to check the stabilizer ballscrew primary load path was required. Loss of the horizontal stabilizer ballscrew primary and secondary load paths, although extremely improbable, could potentially result in the loss of control of the airplane. Boeing Service Related Problem (SRP) 757-SRP-27-0153 is related to this service bulletin.
**NOTE:** Service Bulletin 757-27-0138 served as an interim maintenance action related to 757-SRP-27-0153. Service Bulletin 757-27A0145 is the final maintenance recommendation related to 757-SRP-27-0153. Upon release of Service Bulletin 757-27A0145, operators should perform the maintenance actions in that bulletin rather than those in Service Bulletin 757-27-0138. However, it should be noted that Service Bulletin 757-27-0138 includes one maintenance action that is not included in Service Bulletin 757-27A0145: lubrication of the stabilizer pivot hinges. Lubrication of the stabilizer pivot hinges was included in Service Bulletin 757-27-0138 as a convenience; it is unrelated to the safety issue addressed in safety 757-SRP-27-0153. Boeing recommends that operators continue to perform the stabilizer hinge lubrication task per 757 MPD Volume 1 Section 5, and 757 AMM 12-21-05.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 12 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**Revision 1 is sent to change the compliance times of the detailed inspection, lubrication and ballnut-to-ballscrew freeplay check. Instructions on how to accomplish the detailed inspection are replaced by an instruction to do the detailed inspection in accordance with the Aircraft Maintenance Manual (AMM) and Part 3 is added to the work instructions to give lubrication instructions. Revision 1 also adds an Airworthiness Directive (AD) statement and removes all figures as the procedures are now accomplished by the AMM. These sections were changed: 1. Summary: – Background: A interim notification of a revision to the Maintenance Planning Document (MPD) statement is removed. – Action: The statement is updated to agree with the updated work instructions. – Compliance: An Airworthiness Directive (AD) statement is added. – Manpower: The manpower table is removed. – Illustration: The summary illustration paragraph is updated. 2. Planning Information: – Paragraph 1.A., Effectivity: A group configuration table is added which splits the effectivity into 3 configurations. – Paragraph 1.C., Reason: A interim notification of a revision to the Maintenance Planning Document (MPD) statement is removed. – Paragraph 1.D., Description: The statement is updated to agree with the updated work instructions and maintenance zones are added. – Paragraph 1.E., Compliance: An Airworthiness Directive (AD) statement is added. – Paragraph 1.E., Compliance: The compliance times and the repeat intervals for the detailed inspection, lubrication and freeplay check in Tables 1 and 2 are changed. The corrective action for damaged parts is added, footnotes (a) and (b) are changed and footnote (c) is deleted. – Paragraph 1.E., Compliance: The compliance times and the repeat intervals for the detailed inspection, lubrication and freeplay check in Table 3 are changed. The corrective action for damaged parts is added, footnotes (a) and (b) are changed and footnotes (c) and (d) are deleted. – Paragraph 1.G., Manpower: The manpower table is updated. 3. Accomplishment Instructions: – Paragraph 3.B., Work Instructions: A note is removed from Part 1, Step 1 and the access, cleaning, lubrication and detailed inspection instructions are replaced by one instruction to do a detailed inspection in accordance with the AMM. – Paragraph 3.B., Work Instructions: The access instruction is removed from Part 2 and an AMM task is added to the instruction to do the stabilizer ballscrew to ballnut freeplay check. – Paragraph 3.B., Work Instructions: Part 3 is added to give lubrication instructions. – Figure 1: This Figure is deleted. – Figure 2: This Figure is deleted. – Figure 3: This Figure is deleted. **D. Description** Get access to the horizontal stabilizer trim ballscrew actuator and do the procedures that follow below at the intervals shown in Paragraph 1.E., Compliance:

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 13 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**– Do a detailed inspection of the stabilizer ballscrew assembly. – Lubricate the horizontal stabilizer trim control system. – Do a stabilizer ballscrew to ballnut freeplay check. – Replace damaged and/or cracked and/or worn stabilizer trim ballscrew actuators. Revision 1 - No more work is necessary on airplanes changed in accordance with the original issue of this service bulletin. However, operators must continue with the repeat inspections, lubrication and freeplay checks in accordance with Paragraph 1.E., Compliance. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 311, 312 757-300 **E. Compliance** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 14 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT Group 1, Configuration 1:**  **Table 1 : All airplanes that have not done the overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have completed less than or equal to 15,000 flight hours.** **Repeat Interval (Not to Ex ceed, Whichever Occurs**  **First) Compliance Time (Whichev**  **er Occurs First) Action**  **Condition**

2 years. 3,500 flight hours. Within 2 years from the lastdetailed inspection. Within 3,500 flight hours from the lastdetailed inspection. Detailed inspection of the stabilizer ballscrewassembly in accordance with Paragraph 3.B., Work Instructions, Part 1. All airplanes that have not done the overhaulof the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have completed less than or equal to 15,000 flight hours. 1 year. 2,000 flight hours. Within 1 year from the last lubrication. Within 2,000 flight hours from the last lubrication. Lubricate the horizontal stabilizer trim control system in accordance with Paragraph 3.B., Work Instructions, Part 3. (a) 5 years. 18,000 flight hours. If the Airplane will complete 15,000 total flight hours within 18 months from the date onRevision 1 of this service bulletin, do the freeplay check within 18 months. Stabilizer ballscrew to ballnut freeplay check in accordance with Paragraph 3.B., Work Instructions, Part 2. (b) If the Airplane completes less than 15,000 total flight hours within 18 months from the date on Revision 1 of this service bulletin, do the freeplay check within 15,000 total flight hours or 5 years, whichever occurs first.

- Before further flight. Replace the stabilizer trim ballscrew actuator. Damage and/or cracks and/or excessive wear found on the stabilizer trim ballscrew actuator. (a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check. (b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed inspection before the freeplay check.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 15 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT Group 1, Configuration 2:**  **Table 2 : All airplanes that have not done the overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have completed more than 15,000 flight hours.** **Repeat Interval (Not to Ex ceed, Whichever Occurs**  **First) Compliance Time (Whichev**  **er Occurs First) Action**  **Condition**

2 years. 3,500 flight hours. Within 18 months fromthe last detailed inspection. Within 3,500 flight hours from the lastdetailed inspection. Detailed inspection of the stabilizer ballscrewassembly in accordance with Paragraph 3.B., Work Instructions, Part 1. All airplanes that have not done the overhaulof the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143 and have completed more than 15,000 flight hours. 1 year. 2,000 flight hours. Within 1 year from the last lubrication. Within 2,000 flight hours from the last lubrication. Lubricate the stabilizer trim control system inaccordance with Paragraph 3.B., Work Instructions, Part 3. (a) 5 years. 18,000 flight hours. Within 18 months after the date on Revision 1 of this service bulletin. - Stabilizer ballscrew to ballnut freeplay check in accordance with Paragraph 3.B., Work Instructions, Part 2. (b)

- Before further flight. Replace the stabilizer trim ballscrew actuator. Damage and/or cracks and/or excessive wear found on the stabilizer trim ballscrew actuator. (a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check. (b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed inspection before the freeplay check.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 16 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT Group 1, Configuration 3:**  **Table 3: All airplanes that have done the overhaul of the stabilizer trim actuator in accordance with Service Bulletin 757-27A0143.**  **Repeat Interval (Not to Ex ceed, Whichever Occurs**  **First) Compliance Time (Whichev**  **er Occurs First) Action**  **Condition**

2 years. 3,500 flight hours. Within 2 years from the lastdetailed inspection. Within 3,500 flight hours from the lastdetailed inspection. Detailed inspection of the stabilizer ballscrewassembly in accordance with Paragraph 3.B., Work Instructions, Part 1. All airplanes that have done the overhaul ofthe stabilizer trim actuator in accordance with Service Bulletin 757- 27A0143. 1 year. 2,000 flight hours. Within 1 year from the last lubrication. Within 2,000 flight hours from the last lubrication. Lubricate the horizontal stabilizer trim control system in accordance with Paragraph 3.B., Work Instructions, Part 3. (a) 5 years. 18,000 flight hours. If the Airplane will complete 15,000 total flight hours since overhaul within 18 months from the date on Revision 1 of this service bulletin, do the freeplay check within 18 months. Stabilizer ballscrew to ballnut freeplay check in accordance with Paragraph 3.B., Work Instructions, Part 2. (b) If the Airplane completes less than 15,000 total flight hours since overhaul within 18months from the date on Revision 1 of this service bulletin, do the freeplay check within 15,000 toal flight hours or 5 years, whichever occurs first.

- Before further flight. Replace the stabilizer trim ballscrew actuator. Damage and/or cracks and/or excessive wear found on the stabilizer trim ballscrew actuator. (a) Lubrication is accomplished as a part of either the detailed inspection or the freeplay check. (b) If the detailed inspection and the freeplay check are to be accomplished at the same time, do the detailed inspection before the freeplay check.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 17 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT F. Approval**  This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. **G. Manpower** The table below shows an estimate of the task hours necessary to do the detailed inspection, lubrication and freeplay check 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 examine the work — Time to cure the materials — Time to make the parts — Time to find the tools. **Elapsed Hours Task-Hours**  **Number of Per- sons**  **Task**

2.00 4.00 2 Part 1 - Detailed Inspec- tion 3.00 6.00 2 Part 2 - Freeplay Check 1.50 3.00 2 Part 3 - Lubrication (a) (a) TOTAL FOR EACH AIRPLANE (a) The total task-hours and elapsed hours are not given as the Parts accomplished at the same time are variable. **H. Weight and Balance Changes**
None. **I. Electrical Load Data** Not changed.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 18 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT J. References**  1. Existing Data: a. Boeing Service Bulletin 757-27-0138, 757-27A0143 b. Boeing Service Related Problem (SRP) 757-SRP-27-0153 c. 757 Aircraft Maintenance Manual (AMM) 12-21-05, 27-41-10 d. 757 Maintenance Planning Data (MPD) 757 MPD Volume 1 Section 5 2. Data supplied with this Service Bulletin:
None. 3. Installation Drawings Used in the Preparation of this Service Bulletin:
None. **K. Publications Affected Chapter-Section** 

**Publication** 27-41 757 Aircraft Maintenance Manual **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 19 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 20 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

BLANK PAGE**2. MATERIAL INFORMATION A. Material - Price and Availability** 
None. **B. Industry Support Information** Boeing warranty remedies are not available for the inspections/check given in this service bulletin. **C. Parts Necessary For Each Airplane** 1. Kits/Parts:
None. 2. Parts and Materials Supplied by the Operator:
None. 3. Parts Modified and Reidentified:
None. 4. Parts Removed and Not Replaced: None. **D. Parts Necessary to Change Spares**
None. **E. Special Tooling - Price and Availability**
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.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 21 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 22 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**

BLANK PAGE**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. The instructions identified in Paragraph 3.B., Work Instructions and the Figure(s) give the recommended sequence of steps. The sequence of steps to do this service bulletin can be changed. 2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 3. Obey all of the warnings and cautions given in the specified manual sections. 4. 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 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. **B. WORK INSTRUCTIONS PART 1 : Stabilizer Ballscrew Assembly Detailed Inspection:**  1. Do a detailed inspection of the stabilizer ballscrew assembly in accordance with 757 AMM 27-41-10. 2. Put the airplane back to a serviceable condition. **PART 2 : Stabilizer Ballscrew to Ballnut Freeplay Check:** 1. Do a stabilizer ballscrew to ballnut freeplay check in accordance with 757 AMM 27-41-10. 2. Put the airplane back to a serviceable condition.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 23 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT Part 3: Horizontal Stabilizer Trim Control System Lubrication:**  1. Lubricate the horizontal stabilizer trim control system in accordance with 757 AMM 12-21-05. 2. Put the airplane back to a serviceable condition.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1: January 20, 2010 24 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT FIGURE 1: INSPECTION OF HORIZONTAL STABILIZER BALLSCREW LOAD PATH**  **(SHEET 1 OF 1)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1 January 20, 2010 25 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT FIGURE 2: HORIZONTAL STABILIZER BALLSCREW AND BALLNUT FREEPLAY CHECK**  **(SHEET 1 OF 1)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1 January 20, 2010 26 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT FIGURE 3: HORIZONTAL STABILIZER TRIM BALLSCREW ACTUATOR REPLACEMENT**  **(SHEET 1 OF 1)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: August 07, 2003 757-27A0145 Revision 1 January 20, 2010 27 of 27 **BOEING SERVICE BULLETIN 757-27A0145 ALERT**  **ALERT**