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Proposed Rule

Airworthiness Directives; Boeing Model 737 Airplanes

Document Details

Information about this document as published in the Federal Register.

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Start Preamble

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Boeing Model 737 airplanes. The existing AD currently requires installation of a new rudder control system and changes to the adjacent systems to accommodate that new rudder control system. For certain airplanes, this proposed AD would add, among other actions, repetitive tests of the force fight monitor of the main rudder power control unit (PCU), repetitive tests of the standby hydraulic actuation system, and corrective action; as applicable. For those airplanes, this proposed AD also would add, among other actions, replacement of both input control rods of the main rudder PCU and the input control rod of the standby rudder PCU with new input control rods, as applicable, which would end the repetitive tests. For certain other airplanes, this proposed AD would add installation of an enhanced rudder control system in accordance with new service information. This proposed AD results from a report of a fractured rod end on an input control rod of the main rudder PCU. We are proposing this AD to prevent failure of one of the two input control rods of main rudder PCU, which, under certain conditions, could result in reduced controllability of the airplane; and to prevent failure of any combination of two input control rods of the main rudder PCU and/or standby rudder PCU, which could result in loss of control of the airplane. We are also proposing this AD to prevent an uncommanded rudder hardover event and consequent loss of control of the airplane due to inherent failure modes, including single-jam modes, and certain latent failures or jams combined with a second failure or jam.

DATES:

We must receive comments on this proposed AD by January 2, 2007.

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ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

  • DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
  • Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
  • Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590.
  • Fax: (202) 493-2251.
  • Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for service information identified in this proposed AD.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Kenneth W. Frey, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6468; fax (425) 917-6590.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “Docket No. FAA-2006-26323; Directorate Identifier 2006-NM-150-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or may visit http://dms.dot.gov.

Examining the Docket

You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

On October 30, 2002, we issued AD 2002-20-07 R1, amendment 39-12940 (67 FR 67518, November 6, 2002), for all Boeing Model 737 airplanes. That AD requires installation of a new rudder control system and changes to the adjacent systems to accommodate that new rudder control system. That AD resulted from FAA determinations that the existing system design architecture is unsafe. We issued that AD to prevent an uncommanded rudder hardover event and consequent loss of control of the airplane due to inherent failure modes, including single-jam modes, and certain latent failures or jams combined with a second failure or jam.

Actions Since Existing AD Was Issued

Since the issuance of AD 2002-20-07 R1, we have received a report of a fractured rod end on one of the two input control rods of the main rudder power control unit (PCU) on a Model 737-800 series airplane. This condition was discovered during heavy maintenance. The rod end had not separated from the input control rod and was retained by the sealant used during the assembly of the input control rod. The condition was discovered because the aft rod end of the lower input control rod appeared loose. If the rod end does not separate from the input control rod, there is no indication of fracture and it will not likely be detected during normal flight operation.

If a rod end separates from an input control rod of the main rudder PCU, the input to the A and B sides of the main rudder PCU (the main rudder PCU is a dual tandem actuator) will not match. This condition will cause a force fight between the A and B sides in the main rudder PCU, which will activate the force fight monitor, activate the standby hydraulic system, and illuminate the STBY RUD ON light on the P5-3 panel. Dispatch is not allowed with the STBY RUD ON light illuminated.

The incident airplane had been modified to comply with the requirements of AD 2002-20-07 R1. We previously approved the service bulletins in the table titled “Previously Approved Service Bulletins” as an alternative method of compliance (AMOC) for the requirements of AD 2002-20-07 R1. These service bulletins include procedures to replace both input control rods of the main rudder PCU and the input control rod of the standby rudder PCU (for certain airplanes) with new input control rod(s) having part number (P/N) 251A3495-1, which, we have since determined, had an improper heat treatment during manufacture.

Previously Approved Service Bulletins

For model—Boeing Service Bulletin
737-100, -200, and -200C series airplanes737-27-1252, Revision 2, dated December 9, 2004; Revision 1, dated September 25, 2003; and Original Issue, dated June 26, 2003.
737-300, -400, and -500 series airplanes737-27-1255, Revision 2, dated July 22, 2004; Revision 1, dated June 26, 2003; and Original Issue, dated May 1, 2003.
737-600, -700, -700C, -800, and -900 series airplanes737-27-1253, Revision 2, dated October 7, 2004; Revision 1, dated March 27, 2003; and Original Issue, dated January 2, 2003.

Failure of one of the two input control rods of the main rudder PCU under certain conditions, if not corrected, could result in reduced controllability of the airplane. Failure of any combination of two input control rods of the main rudder PCU and/or standby rudder PCU, if not corrected, could result in loss of control of the airplane. Start Printed Page 66476

Relevant Service Information

We have reviewed the service bulletins in the table titled “Service Bulletins for Repetitive Tests and Other Actions.” The service bulletins specify an initial compliance time for doing the initial test of the standby system of within 60 days after the date of the service bulletin, and a repetitive interval of 500 flight hours. The service bulletins also specify an initial compliance time for doing the initial test of the force fight monitor of within 90 days or 6,000 flight hours after the date of the service bulletin, depending on the airplane configuration, and a repetitive interval of 6,000 flight hours. For airplanes identified as Groups 1 and 2, Configuration 2, in Boeing Alert Service Bulletin 737-27A1281, dated June 14, 2006; and airplanes identified as Group 1, Configuration 2, in Boeing Alert Service Bulletin 737-27A1280, dated May 25, 2006; no work is necessary in accordance with these service bulletins. The improperly heat-treated control rods were not installed on those airplanes.

Service Bulletins for Repetitive Tests and Other Actions

For certain model—Boeing Alert Service BulletinDescribes procedures for doing—
737-600, -700, -700C, -800 and -900 series airplanes737-27A1280, dated May 25, 2005The “Rudder Main Power Control Unit Force Fight Monitor Test,” the “Operational Test of the Standby Hydraulic Actuation System,” and applicable corrective action if necessary.
737-100, -200, -200C, -300, -400, and -500 series airplanes737-27A1281, dated June 14, 2006The “Rudder Main Power Control Unit Force Fight Test,” the “Standby Rudder Actuator Shutoff Valve Test,” and applicable corrective action if necessary.

We also have reviewed the service bulletins in the table titled, “Service Bulletins for Installation of an RSEP and Replacement of Input control rods.” Boeing uses the acronym RSEP for the “Rudder System Enhancement Program.” \

Service Bulletins for Installation of an RSEP and Replacement of Input Control Rods

For certain model—Boeing—Describes procedures for—Which ends the repetitive tests specified in Boeing Service Bulletin—
737-100, -200, and -200C series airplanesService Bulletin 737-27-1252, Revision 3, dated May 12, 2006Installing an RSEP (Part 1), and replacing both input control rods of the main rudder PCU with new input control rods (Part 2)737-27A1281, dated June 14, 2006.
737-300, -400, and -500 series airplanesService Bulletin 737-27-1255, Revision 3, dated May 10, 2006Installing an RSEP (Part 1), and replacing both input control rods of the main rudder PCU with new input control rods (Part 2)737-27A1281, dated June 14, 2006.
737-600, -700, -700C, -800, and -900 series airplanesService Bulletin 737-27-1253, Revision 3, dated May 12, 2006Installing an RSEP (Part 1); and replacing both input control rods of the main rudder PCU with new input control rods, inspecting the control rod of the standby rudder PCU to determine if part number (P/N) 251A3495-1 is installed, and doing corrective action if necessary (Part 2) (i.e., replacing any improperly heat-treated input control rod with a new input control rod)737-27A1280, dated May 25, 2005.
Alert Service Bulletin 737-27A1279, dated June 20, 2006Replacing both input control rods of the main rudder PCU and the input control rod of the standby rudder PCU with new input control rod(s)737-27A1280, dated May 25, 2005.

Boeing Alert Service Bulletins 737-27-1252, 737-27-1253, and 737-27-1255, all Revision 3, also specify prior or concurrent accomplishment of the actions described in the table titled, “Prior/Concurrent Service Information.”

Prior/Concurrent Service Information

Prior to or concurrently with the actions in Boeing Alert Service Bulletin—Do this action—In accordance with—
737-27-1252, Revision 3, dated May 12, 2006Remove the rudder position sensor of the automatic flight control systemBoeing Service Bulletin 737-22-1042, Revision 1, dated April 5, 1985.
Replace the rudder feel and centering assembly with a new all-mechanical unitBoeing Service Bulletin 737-27-1026, dated January 15, 1971.
Install the rudder pressure reducer and yaw damper couplerBoeing Service Bulletin 737-27A1206, Revision 3, dated December 14, 2000.
Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1246, Revision 1, dated February 21, 2002.
Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1263, Revision 1, dated September 25, 2003.
Start Printed Page 66477
Replace the input lever for the auxiliary rudder power control package with a new input leverSmiths Aerospace Service Bulletin 1150-27-05A, dated August 28, 2003.
737-27-1253, Revision 3, dated May 12, 2006Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1247, Revision 1, dated July 25, 2002.
Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1262, dated December 19, 2002.
Relocate the wire bundle routing in the vertical stabilizerBoeing Alert Service Bulletin 737-27A1239, dated January 11, 2001.
737-27-1255, Revision 3, dated May 10, 2006Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1246, Revision 1, dated February 21, 2002.
Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1265, Revision 1, dated April 3, 2003.
Install a new yaw damper couplerBoeing Service Bulletin 737-27A1206, Revision 3, dated December 14, 2000.
Inspect and rework the trailing edge beam on the vertical finBoeing Service Bulletin 737-55-1052, Revision 1, dated August 5, 2004.
Replace the input lever for the auxiliary rudder power control package with a new input leverSmiths Aerospace Service Bulletin 1150-27-05A, dated August 28, 2003.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2002-20-07 R1 and would retain the requirements of the existing AD. This proposed AD would also require accomplishing the actions specified in the applicable service information described previously. For certain airplanes, this proposed AD also would require suspending a certain Master Minimum Equipment Item, until the improperly heat-treated input control rods are replaced.

Change to Existing AD

This proposed AD would retain all requirements of AD 2002-20-07 R1. Since AD 2002-20-07 R1 was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 2002-20-07 R1Corresponding requirement in this proposed AD
paragraph (a)paragraph (f).
paragraph (b)paragraph (b) (with new title).

Costs of Compliance

There are about 6,412 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 1,678 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD. The average labor rate is $80 per work hour.

Estimated Costs

ActionWork hoursPartsCost per airplaneFleet cost
Installation of rudder control system (required by AD 2002-20-07 R1, and retained in this NPRM)700$140,000$196,000$328,888,000.
Repetitive tests, per test cycle (new action proposed by this NPRM)2None$160, per test cycleUp to $268,480 depending on the configuration of the airplanes.
Replacement of the input control rods (new action proposed by this NPRM) (ends repetitive tests)5 to 7The manufacturer states that it will supply required parts to the operators at no cost$400 to $560Up to $939,680, depending the configuration of the airplanes.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition Start Printed Page 66478that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the National Government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-12940 (67 FR 67518, November 6, 2002) and adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2006-26323; Directorate Identifier 2006-NM-150-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by January 2, 2007.

Affected ADs

(b) This AD affects the ADs specified in paragraphs (b)(1), (b)(2), and (b)(3) of this AD.

(1) This AD supersedes AD 2002-20-07 R1.

(2) For airplanes on which the actions required by paragraph (f) of this AD have been done before the effective date of this AD: Doing the actions in paragraph (f) of this AD ends the requirements of the ADs listed in Table 1 of this AD.

(3) For airplanes on which the actions required by paragraph (f) of this AD have not been done before the effective date of this AD: Doing the actions in paragraph (h) of this AD ends the requirements of the ADs listed in Table 1 of this AD.

Table 1.—Other ADs

ADAmendment
97-09-15 R139-10912
99-11-0539-11175
2000-22-02 R139-11948

Applicability

(c) This AD applies to all Boeing Model 737-100, -200, -200C, -300, -400, -500, -600, -700,-700C, -800 and -900 series airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from a report of a fractured rod end on an input control rod of the main rudder power control unit (PCU). We are issuing this AD to prevent failure of one of the two input control rods of the main rudder PCU, which, under certain conditions, could result in reduced controllability of the airplane; and to prevent failure of any combination of two input control rods of the main rudder PCU and/or standby rudder PCU, which could result in loss of control of the airplane. We are also issuing this AD to prevent an uncommanded rudder hardover event and consequent loss of control of the airplane due to inherent failure modes, including single-jam modes, and certain latent failures or jams combined with a second failure or jam.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Requirements of AD 2002-20-07 R1

Installation

(f) Except as provided by paragraphs (h) and (i) of this AD: Within 6 years after November 12, 2002 (the effective date of AD 2002-20-07), do the actions required by paragraphs (f)(1) and (f)(2) of this AD, in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA.

(1) Install a new rudder control system that includes new components such as an aft torque tube, hydraulic actuators, and associated input control rods, and additional wiring throughout the airplane to support failure annunciation of the rudder control system in the flight deck. The system also must incorporate two separate inputs, each with an override mechanism, to two separate servo valves on the main rudder PCU; and an input to the standby PCU that also will include an override mechanism.

(2) Make applicable changes to the adjacent systems to accommodate the new rudder control system.

New Requirements of This AD

For Certain Airplanes: Tests, Suspension of Certain Master Minimum Equipment Item, Replacements, Inspection, and Corrective Actions

(g) For airplanes on which the actions required by paragraph (f) of this AD have been done before the effective date of this AD: Do the actions in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, as applicable.

(1) At the applicable times listed in paragraph 1.E., “Compliance,” of the applicable service bulletin specified in Table 2 of this AD; except, where the service bulletin specifies a compliance time from the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD: Do the tests specified in Table 2 of this AD, until the installation required by paragraph (g)(3) of this AD has been done in accordance with the applicable service bulletin in Table 3 of this AD. Do all applicable corrective actions specified in Table 2 of this AD before further flight.

Table 2.—Repetitive Tests

For model—Identified as—Do—In accordance with the accomplishment instructions of—
(i) 737-100, -200, and -200C series airplanesGroup 1, Configuration 1 in the service bulletinThe “Rudder Main Power Control Unit Force Fight Test,” the “Standby Rudder Actuator Shutoff Valve Test,” and any applicable corrective actionBoeing Alert Service Bulletin 737-27A1281, dated June 14, 2006.
(ii) 737-300, -400, and -500 series airplanesGroup 2, Configuration 1 in the service bulletinThe “Rudder Main Power Control Unit Force Fight Test,” the “Standby Rudder Actuator Shutoff Valve Test,” and any applicable corrective actionBoeing Alert Service Bulletin 737-27A1281, dated June 14, 2006.
Start Printed Page 66479
(iii) 737-600, -700, -700C, -800, and -900 series airplanesGroup 1, Configuration 1 and Group 2, Configurations 1 and 2 in the service bulletinThe “Rudder Main Power Control Unit Force Fight Monitor Test,” the “Operational Test of the Standby Hydraulic Actuation System,” and any applicable corrective actionBoeing Alert Service Bulletin 737-27A1280, dated May 25, 2005.

(2) As of the effective date of this AD, do not use the Master Minimum Equipment Item 27-21, “STBY RUD ON light,” until the actions required by paragraph (g)(3) of this AD are done.

(3) Within 24 months after the effective date of this AD, do the replacement(s) and inspection, as applicable, specified in Table 3 of this AD. Do all applicable corrective actions specified in Table 3 of this AD before further flight. Doing the applicable action(s) ends the requirements of paragraphs (g)(1) and (g)(2) of this AD.

Table 3.—Replacement of Input Control Rods, Inspection, and Corrective Action, as Applicable

For Model—Identified as—Do the following action(s)—In accordance with—
(i) 737-100, -200, and -200C series airplanesGroups 1 through 9, Configuration 3 in the service bulletinReplace both input control rods of the main rudder PCU with new input control rodsPart 2 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1252, Revision 3, dated May 12, 2006.
(ii) 737-300, -400, and -500 series airplanesGroups 1 through 19, Configuration 3 in the service bulletinReplace both input control rods of the main rudder PCU with new input control rodsPart 2 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1255, Revision 3, dated May 10, 2006.
(iii) 737-600, -700, -700C, -800, and -900 series airplanesGroups 1 through 20, Configuration 3 in the service bulletinReplace both input control rods of the main rudder PCU with new input control rods, inspect the input control rod of the standby rudder PCU to determine if part number (P/N) 251A3495-1 is installed, and any corrective actionPart 2 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1253, Revision 3, dated May 12, 2006.
(iv) 737-600, -700, -700C, -800, and -900 series airplanesGroup 1 in the service bulletinReplace both input control rods of the main rudder PCU and the input control rod of the standby rudder PCU with a new input control rod(s)The Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1279, dated June 20, 2006.

For Certain Other Airplanes: Install New Rudder Control System per Service Information

(h) For airplanes on which the actions required by paragraph (f) of this AD have not been done before the effective date of this AD: As of the effective date of this AD, use the applicable service bulletin specified in Table 4 of this AD to do the actions required by paragraph (f) of this AD at the time specified in that paragraph.

Table 4.—Service Bulletins for Installation of New Rudder Control System

For model—Identified as—Do the actions required by paragraph (f) of this AD in accordance with—
(1) 737-100, -200, and -200C series airplanesGroups 1 through 9, Configurations 1 and 2 in the service bulletinPart 1 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1252, Revision 3, dated May 12, 2006.
(2) 737-300, -400, and -500 series airplanesGroups 1 through 19, Configurations 1 and 2 in the service bulletinPart 1 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1255, Revision 3, dated May 10, 2006.
(3) 737-600, -700, -700C, -800, and -900 series airplanesGroups 1 through 20, Configurations 1 and 2 in the service bulletinPart 1 of the Accomplishment Instructions of Boeing Service Bulletin 737-27-1253, Revision 3, dated May 12, 2006.

(i) Before or concurrently with the requirements of paragraph (h) of this AD, do the actions in Table 5 of this AD. Start Printed Page 66480

Table 5.—Before/Concurrent Requirements

Before or concurrently with the actions specified in—Do these actions—In accordance with the accomplishment instructions of—
(1) Paragraph (h)(1) of this AD(i) Remove the rudder position sensor of the automatic flight control systemBoeing Service Bulletin 737-22-1042, Revision 1, dated April 5, 1985.
(ii) Replace the rudder feel and centering assembly with a new all-mechanical unitBoeing 737 Service Bulletin 27-1026, dated January 15, 1971.
(iii) Install the rudder pressure reducer and yaw damper couplerBoeing Service Bulletin 737-27A1206, Revision 3, dated December 14, 2000.
(iv) Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1246, Revision 1, dated February 21, 2002.
(v) Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1263, Revision 1, dated September 25, 2003.
(vi) Replace the input lever for the auxiliary rudder power control package with a new input leverSmiths Aerospace Service Bulletin 1150-27-05A, dated August 28, 2003.
(2) Paragraph (h)(2) of this AD(i) Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1246, Revision 1, dated February 21, 2002.
(ii) Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1264, Revision 1, dated April 3, 2003.
(iii) Install a new yaw damper couplerBoeing Service Bulletin 737-27A1206, Revision 3, dated December 14, 2000.
(iv) Inspect the trailing edge beam on the vertical fin and rework if necessaryBoeing Service Bulletin 737-55-1052, Revision 1, dated August 5, 2004.
(v) Replace the input lever for the auxiliary rudder power control package with a new input leverSmiths Aerospace Service Bulletin 1150-27-05A, dated August 28, 2003.
(3) Paragraph (h)(3) of this AD(i) Install provisional wires for rudder system enhancementBoeing Service Bulletin 737-27-1247, Revision 1, dated July 25, 2002.
(ii) Replace the P5-3 panel with a new panelBoeing Service Bulletin 737-27-1262, dated December 19, 2002.
(iii) Relocate the wire bundle routing in the vertical stabilizerBoeing Alert Service Bulletin 737-27A1239, dated January 11, 2001.

Parts Installation

(j) As of the effective date of this AD, no person may install an input control rod, P/N 251A3495-1, on any airplane.

Alternative Methods of Compliance (AMOCs)

(k)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

(3) Except as provided by paragraph (j) of this AD: AMOCs approved previously in accordance with AD 2002-20-07 R1 are approved as AMOCs for the corresponding provisions of paragraphs (f) and (h) of this AD.

Start Signature

Issued in Renton, Washington, on November 3, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. E6-19227 Filed 11-14-06; 8:45 am]

BILLING CODE 4910-13-P