2010-20556. Airworthiness Directives; The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER Series Airplanes

AGENCY:

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

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is superseding an existing airworthiness directive (AD) that applies to all Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. The existing AD currently requires, for certain airplanes, a one-time detailed inspection of the inboard and outboard aft attach lugs of the left and right elevator tab control mechanisms for discrepancies, and replacement of any discrepant elevator tab control mechanism. For certain other airplanes, the existing AD requires that the inspections be done repetitively. Replacing the elevator tab control mechanism with a new Boeing-built mechanism terminates the repetitive inspections in the existing AD. This new AD requires that modified repetitive inspections be done on all airplanes, regardless of accomplishment of the terminating action specified in the existing AD. This AD results from reports of failure of the aft attach lugs on the elevator tab control mechanisms, which resulted in severe elevator vibration. This AD also results from reports of gaps in elevator tab control mechanisms and analysis that additional elevator tab control mechanisms might have bearings that will come loose. We are issuing this AD to detect and correct discrepancies in the aft attach lugs of the elevator tab control mechanism, which could result in elevator and tab vibration. Consequent structural failure of the elevator or horizontal stabilizer could result in loss of structural integrity and aircraft control.

DATES:

This AD becomes effective September 9, 2010.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of September 9, 2010.

On April 29, 2010 (75 FR 21499, April 26, 2010), the Director of the Federal Register approved the incorporation by reference of a certain other publication listed in the AD.

We must receive any comments on this AD by October 12, 2010.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com.

Examining the AD Docket

You may examine the AD docket on the Internet at http://;www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Kelly McGuckin, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Discussion

On April 19, 2010, we issued AD 2010-09-05, amendment 39-16270 (75 FR 21499, April 26, 2010). That AD applies to all Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. That AD requires, for certain airplanes, a one-time detailed inspection of the inboard and outboard aft attach lugs of the left and right elevator tab control mechanisms for discrepancies, and replacement of any discrepant elevator tab control mechanism (the replacement includes performing the detailed inspection on the replacement part before and after installation, and corrective actions if necessary). For certain other airplanes, that AD requires repetitive inspections for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator tab control mechanisms, and replacement if necessary. For airplanes on which the elevator tab control mechanism is replaced with a certain mechanism, that AD requires repetitive inspections for discrepancies of the elevator tab control mechanism and replacement if necessary. Replacing the elevator tab control mechanism with a new Boeing-built mechanism terminates the repetitive inspections in that AD. That AD resulted from reports of failure of the aft attach lugs on the elevator tab control mechanisms, which resulted in severe elevator vibration. One event occurred on an airplane on which a previous AD (emergency AD 2010-06-51, Amendment 39-16250 (75 FR 16648, April 2, 2010)) had been done. The actions specified in AD 2010-09-05 are intended to detect and correct discrepancies in the aft attach lugs of the elevator tab control mechanism, which could result in unwanted elevator and tab vibration. Consequent structural failure of the elevator or horizontal stabilizer could result in loss of structural integrity and aircraft control.

Actions Since AD 2010-09-05 Was Issued

Since we issued AD 2010-09-05, we have received reports of gaps and loose bearings. For Boeing-built mechanisms, we received reports of gaps but no reports of loose bearings. Also, additional analysis has shown that non-Boeing-built mechanisms installed on airplanes having Line Number 2708 and subsequent might have bearings that will come loose. We have determined that the identified unsafe condition is related to the design of the elevator tab control mechanism. Therefore, all airplanes identified in the applicability of this AD must be repetitively inspected. In addition, installing a Boeing-built mechanism is no longer terminating action for the repetitive inspections.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010. This service bulletin describes procedures for repetitive inspections for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator tab control mechanisms, and replacement if necessary. We referred to Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, as the appropriate source of service information for accomplishing certain required actions in AD 2010-09-05. Boeing Alert Service Bulletin 737-27A1297, Revision 1, no longer specifies that installing a Boeing-built mechanism ends the repetitive inspections. Boeing Alert Service Bulletin 737-27A1297, Revision 1, also modifies the inspection procedure by expanding the allowable gap depth in the lug-to-lug interface and the lug-to-spacer interface. Boeing Alert Service Bulletin 737-27A1297, Revision 1, also removes the procedure to determine if replacement mechanisms are Boeing-built or non-Boeing-built.

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other airplanes of the same type design. For this reason, we are issuing this AD to supersede AD 2010-09-05. This new AD retains certain requirements of the existing AD. This AD also requires accomplishing the actions specified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010, described previously, except this AD does not require sending discrepant elevator tab control mechanisms to the manufacturer. This AD does require sending the inspection results to the manufacturer.

Change to Existing AD

This AD retains certain requirements of AD 2010-09-05. As a result, the corresponding paragraph identifiers have changed in this AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 2010-09-05	Corresponding requirement in this AD
paragraph (m)	paragraph (g)
paragraph (n)	paragraph (h)
paragraph (o)	paragraph (i)
paragraph (p)	paragraph (j)
paragraph (q)	paragraph (k)
paragraph (r)	paragraph (l)
paragraph (s)	paragraph (m)

Interim Action

This AD is considered to be interim action. The manufacturer is currently developing a terminating action that will address the unsafe condition identified in this AD. Once final action has been identified, we might consider further rulemaking.

FAA's Justification and Determination of the Effective Date

Discrepancies, including loose bearings, in the aft attach lugs of the elevator tab control mechanism could result in elevator and tab vibration. Consequent structural failure of the elevator or horizontal stabilizer could result in loss of structural integrity and aircraft control. Because of our requirement to promote safe flight of civil aircraft and thus, the critical need to ensure the structural integrity of the airplane and the short compliance time involved with this action, this AD must be issued immediately.

Because an unsafe condition exists that requires the immediate adoption of this AD, we find that notice and opportunity for prior public comment hereon are impracticable and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments before it becomes effective. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-0798; Directorate Identifier 2010-NM-174-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD.

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 that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will 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 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 AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

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

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

§ 39.13

[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-16270 ( 75 FR 21499, April 26, 2010) and by adding the following new airworthiness directive (AD):

2010-17-19 The Boeing Company: Amendment 39-16413. Docket No. FAA-2010-0798; Directorate Identifier 2010-NM-174-AD.

Effective Date

(a) This AD becomes effective September 9, 2010.

Affected ADs

(b) This AD supersedes AD 2010-09-05, Amendment 39-16270.

Applicability

(c) This AD applies to all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes; certificated in any category.

Subject

(d) Air Transport Association (ATA) of America Code 27: Flight controls.

Unsafe Condition

(e) This AD results from reports of failure of the aft attach lugs on elevator tab control mechanisms, which resulted in severe elevator vibration. This AD also results from reports of gaps in elevator tab control mechanisms and analysis that additional elevator tab control mechanisms might have bearings that will come loose. The Federal Aviation Administration is issuing this AD to detect and correct discrepancies in the aft attach lugs of the elevator tab control mechanism, which could result in elevator and tab vibration. Consequent structural failure of the elevator or horizontal stabilizer could result in loss of structural integrity and aircraft control.

Compliance

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

Restatement of Certain Requirements of AD 2010-09-05, With Revised Terminating Action

Repetitive Inspections for Group 1 Airplanes, as Identified in Boeing Alert Service Bulletin 737-27A1297, Dated April 16, 2010

(g) For Group 1 airplanes, as identified in Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010: Except as required by paragraph (h) of this AD, within 12 days after April 29, 2010 (the effective date of AD 2010-09-05), do a detailed inspection for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator control tab mechanisms, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010. Repeat the inspection thereafter at intervals not to exceed 300 flight hours. Doing the replacement specified in paragraph (l) of this AD before the effective date of this AD terminates the requirements of this paragraph. Doing the inspection required by paragraph (n) of this AD terminates the requirements of this paragraph.

(h) For Group 1 airplanes as identified in Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010: Beginning 7 days after April 29, 2010, no person may operate an airplane on an extended twin operations (ETOPS) flight unless the initial inspection required by paragraph (g) of this AD has been accomplished. Doing the inspection required by paragraph (n) of this AD terminates the requirements of this paragraph.

One-Time Inspection for Group 2, Configuration 1 Airplanes, as Identified in Boeing Alert Service Bulletin 737-27A1297, Dated April 16, 2010

(i) For Group 2, Configuration 1 airplanes as identified in Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010: Within 30 days after April 29, 2010, do a one-time detailed inspection for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator control tab mechanisms, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010. Doing the inspection required by paragraph (n) of this AD terminates the requirements of this paragraph.

Corrective Actions for Paragraphs (g), (i), and (k) of This AD

(j) If, during any inspection required by paragraph (g), (i), or (k) of this AD, any discrepancy is found, before further flight, replace the elevator tab control mechanism by doing the actions specified in paragraphs (j)(1) and (j)(2) of this AD.

(1) Do a detailed inspection for discrepancies of the replacement elevator tab control mechanism; and, if no discrepancy is found, install the replacement elevator tab control mechanism; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010. If any discrepancy is found, then that elevator tab control mechanism cannot be installed and the actions specified in this paragraph must be done before further flight on another replacement elevator tab control mechanism.

(2) Re-inspect the installed elevator tab control mechanism using the inspection procedure specified in paragraph (i) of this AD.

Repetitive Inspections for Certain Group 2, Configuration 1 Airplanes, as Identified in Boeing Alert Service Bulletin 737-27A1297, Dated April 16, 2010

(k) For Group 2, Configuration 1 airplanes as identified in Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, on which the elevator control tab mechanism is replaced with a mechanism other than a new, Boeing-built mechanism: Within 300 flight hours after doing the replacement, do a detailed inspection for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator control tab mechanisms, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010. Repeat the inspection thereafter at intervals not to exceed 300 flight hours. Doing the replacement specified in paragraph (l) of this AD before the effective date of this AD is terminating action for this paragraph. Doing the inspection required by paragraph (n) of this AD terminates the requirements of this paragraph.

Terminating Action for Paragraphs (g), (i), and (k) of This AD, if Done Before the Effective Date of This AD

(l) Replacing an elevator tab mechanism with a new, Boeing-built mechanism before the effective date of this AD, as specified in paragraphs (l)(1) and (l)(2) of this AD, terminates the inspections required by paragraphs (g), (i), and (k) of this AD. Replacement of the elevator tab control mechanism on or after the effective date of this AD does not terminate the inspections required by paragraphs (g), (i), and (k) of this AD.

Note 1:

Refer to paragraphs 3.B.7.b.(1)(a)(1) and 3.B.7.b.(1)(a)(2) of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, to establish whether the mechanism is Boeing-built.

(1) Do a detailed inspection for discrepancies of the new, Boeing-built replacement elevator tab control mechanism; and, if no discrepancy is found, install the replacement elevator tab control mechanism; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010. If any discrepancy is found, then that elevator tab control mechanism cannot be installed and the actions specified in this paragraph must be done on another new, Boeing-built replacement elevator tab control mechanism.

(2) Re-inspect the installed elevator tab control mechanism using the inspection procedure specified in paragraph (i) of this AD.

Reporting for Paragraphs (g), (i), and (k) of This AD

(m) At the applicable time specified in paragraph (m)(1) or (m)(2) of this AD: Submit a report of any findings (positive and negative) of the first inspection required by paragraphs (g), (i), and (k) of this AD, and any positive findings from the repetitive inspections required by paragraphs (g) and (k) of this AD, to Boeing Commercial Airplanes Group, Attention: Manager, Airline Support, e-mail: [e-mail]. The report must include the inspection results including a description of any discrepancies found, the airplane line number, and the total number of flight cycles and flight hours accumulated on the airplane. Under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056.

(1) If the inspection was done on or after April 29, 2010: Submit the report within 10 days after the inspection.

(2) If the inspection was done before April 29, 2010: Submit the report within 10 days after April 29, 2010.

New Requirements of This AD

Repetitive Inspections

(n) At the applicable time specified in paragraph (n)(1), (n)(2), or (n)(3) of this AD: Do a detailed inspection for discrepancies of the inboard and outboard aft attach lugs of the left and right elevator tab control mechanisms, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010. For Groups 1 and 2 airplanes identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010, repeat the inspection thereafter at intervals not to exceed 300 flight hours, except as provided by paragraph (t)(2) of this AD. For Group 3 airplanes identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010, repeat the inspection thereafter at intervals not to exceed 1,800 flight hours, except as required by paragraphs (p) and (t)(2) of this AD. Doing the inspection specified in this paragraph terminates the requirements of paragraphs (g), (h), (i), and (k) of this AD.

(1) For Group 1 airplanes identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010: Within 300 flight hours after doing an inspection in accordance with Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, or within 30 days after the effective date of this AD, whichever occurs later.

(2) For Group 2 airplanes identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010: At the later of the times specified in paragraph (n)(2)(i) and (n)(2)(ii) of this AD.

(i) Before the accumulation of 2,000 total flight cycles or 4,000 total flight hours, whichever occurs first.

(ii) Within 14 days after the effective date of this AD.

(3) For Group 3 airplanes identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010: Within 180 days or 1,800 flight hours after the effective date of this AD, whichever occurs first.

Corrective Actions

(o) If, during any inspection required by paragraph (n) or (p) of this AD, any discrepancy is found, before further flight, replace the elevator tab control mechanism by doing the actions specified in paragraphs (o)(1) and (o)(2) of this AD.

(1) Do a detailed inspection for discrepancies of the replacement elevator tab control mechanism; and, if no discrepancy is found, install the replacement elevator tab control mechanism; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010. If any discrepancy is found, then that elevator tab control mechanism cannot be installed and the actions specified in this paragraph must be done before further flight on another replacement elevator tab control mechanism.

(2) Re-inspect the installed elevator tab control mechanism using the inspection procedure specified in paragraph (n) of this AD.

Reduced Repetitive Inspection Interval for Group 3 Airplanes, as Identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, on Which the Mechanism Is Replaced

(p) For Group 3 airplanes as identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010, on which the elevator tab control mechanism is replaced during the actions required by paragraph (o) of this AD: Within 300 flight hours after doing the replacement, do a detailed inspection for discrepancies of the inboard and outboard aft attach lugs of the replaced elevator tab control mechanism, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010. Repeat the inspection of the replaced elevator tab control mechanism thereafter at intervals not to exceed 300 flight hours, except as provided by paragraph (t)(2) of this AD.

Credit for Initial Inspection Done in Accordance With the Original Issue of the Service Bulletin

(q) For Group 1 airplanes as identified in Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010: Inspections done in accordance with Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, are acceptable for compliance with only the initial inspection required by paragraph (n) of this AD.

Reporting for Paragraphs (n) and (p) of This AD

(r) At the applicable time specified in paragraph (r)(1) or (r)(2) of this AD: Submit a report of any findings (positive and negative) of the first inspection required by paragraphs (n) and (p) of this AD, except for airplanes on which a report required by paragraph (m) of this AD has been submitted, only submit positive findings; and submit a report of any positive findings from the repetitive inspections required by paragraphs (n) and (p) of this AD; to Boeing Commercial Airplanes Group, Attention: Manager, Airline Support, e-mail: [e-mail]. The report must include the inspection results including a description of any discrepancies found, the airplane line number, and the total number of flight cycles and flight hours accumulated on the airplane. Under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056.

(1) If the inspection was done on or after the effective date of this AD: Submit the report within 10 days after the inspection.

(2) If the inspection was done before the effective date of this AD: Submit the report within 10 days after the effective date of this AD.

No Return of Parts

(s) Although Boeing Alert Service Bulletins 737-27A1297, dated April 16, 2010; and Revision 1, dated August 2, 2010; specify to return the affected elevator tab control mechanism to the manufacturer, this AD does not require the return of the part to the manufacturer.

Parts Installation

(t) As of the effective date of this AD, comply with the conditions specified in paragraphs (t)(1) and (t)(2) of this AD.

(1) No person may install an elevator tab control mechanism, part number 251A2430-( ), on any airplane, unless the mechanism has been inspected before and after installation using the inspection procedures specified in paragraphs (o)(1) and (o)(2) of this AD, and no discrepancies have been found.

(2) An elevator tab control mechanism, part number 251A2430-( ), may be installed, provided that the inspection specified in paragraph (n) of this AD is done within 300 flight hours after doing the installation, and that the inspection specified in paragraph (n) of this AD is repeated thereafter at intervals not to exceed 300 flight hours.

Alternative Methods of Compliance (AMOCs)

(u)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Kelly McGuckin, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Information may be e-mailed to: [e-mail].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(4) AMOCs approved previously in accordance with AD 2010-09-05, amendment 39-16270, are approved as AMOCs for the corresponding provisions of paragraphs (g), (h), (i), (j), and (k) of this AD.

Material Incorporated by Reference

(v) You must use Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010; and Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010; as applicable; to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 737-27A1297, Revision 1, dated August 2, 2010, under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The Director of the Federal Register previously approved the incorporation by reference of Boeing Alert Service Bulletin 737-27A1297, dated April 16, 2010, on April 29, 2010 (75 FR 21499, April 26, 2010).

(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com.

(4) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

(5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on August 11, 2010.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.