Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

We are revising an existing airworthiness directive (AD) that applies to certain Boeing Model 737-300, -400, and -500 series airplanes. That AD currently requires repetitive high frequency eddy current inspections for cracking of the 1.04-inch nominal diameter wire penetration hole in the frame and frame reinforcement, between stringers S-20 and S-21, on both the left and right sides of the airplane, and related investigative and corrective actions if necessary. This new AD clarifies certain compliance requirements. This AD results from reports of cracking in the frame, or in the frame and frame reinforcement, common to the 1.04-inch nominal diameter wire penetration hole intended for wire routing. We are issuing this AD to detect and correct cracking in the fuselage frames and frame reinforcements, which could reduce the structural capability of the frames to sustain limit loads, and result in cracking in the fuselage skin and subsequent rapid depressurization of the airplane.

DATES:

This AD is effective September 23, 2009.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of April 15, 2009 (74 FR 10469, March 11, 2009).

We must receive comments on this AD by November 9, 2009.

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: 202-493-2251.
• 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 206-544-5000, extension 1, fax 206-766-5680; e-mail me.boecom@boeing.com; 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 800-647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Wayne Lockett, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6447; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Discussion

On January 9, 2009, we issued AD 2009-02-06, amendment 39-15796 (74 FR 10469, March 11, 2009), for certain Boeing Model 737-300, -400, and -500 series airplanes. That AD requires repetitive high frequency eddy current inspections for cracking of the 1.04-inch nominal diameter wire penetration hole in the frame and frame reinforcement, between stringers S-20 and S-21, on both the left and right sides of the airplane, and related investigative and corrective actions if necessary. That AD resulted from reports of cracking in the frame, or in the frame and frame reinforcement, common to the 1.04-inch nominal diameter wire penetration hole intended for wire routing. We issued that AD to detect and correct cracking in the fuselage frames and frame reinforcements, which could reduce the structural capability of the frames to sustain limit loads, and result in cracking in the fuselage skin and subsequent rapid depressurization of the airplane.

Actions Since Existing AD Was Issued

Since we issued AD 2009-02-06, January 9, 2009, amendment 39-15796 (74 FR 10469, March 11, 2009), we have determined that we need to clarify certain compliance requirements in the existing AD, as follows:

• We have inserted a new paragraph (g)(1) in this AD to state that while the service bulletin specifies compliance times in terms of the “date on this service bulletin,” this AD requires compliance within the specified compliance time “after the effective date of this AD.” This paragraph appeared in the original NPRM, but was inadvertently removed from AD 2009-02-06.
• We removed the reference to the “Accomplishment Instructions” of Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007, from paragraph (g) of this AD. Paragraphs (g)(1) through (g)(4) of this AD do not all refer to text located in the service bulletin Accomplishment Instructions.
• We added a reference to the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007, to paragraph (i) of this AD to provide the locations of “Part 3” and “Part 5,” as referenced in that paragraph of the AD.

Changes to Existing AD

This AD retains all the requirements of AD 2009-02-06. Since AD 2009-02-06 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 AD, as listed in the following table:

FAA's Determination and Requirements of This AD

We are issuing this AD because the unsafe condition described previously is likely to exist or develop on other products of these same type designs that could be registered in the United States in the future. This AD revises AD 2009-02-06. This AD retains the requirements of the existing AD and clarifies certain compliance requirements. Since no new airplanes are affected by this AD and there are no new required actions, notice and opportunity for public comment before issuing this AD are unnecessary.

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-2009-0787; Directorate Identifier 2009-NM-090-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

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 this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Is not a “significant rule” under 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.

You can find our regulatory evaluation and the estimated costs of compliance in the AD docket.

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 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.

2. The FAA amends § 39.13 by removing amendment 39-15796 ( 74 FR 10469, March 11, 2009) and adding the following new AD:

2009-02-06 R1 Boeing: Amendment 39-16015. Docket No. FAA-2009-0787; Directorate Identifier 2009-NM-090-AD.

Effective Date

(a) This airworthiness directive (AD) is effective September 23, 2009.

Affected ADs

(b) This AD revises AD 2009-02-06.

Applicability

(c) This AD applies to Boeing Model 737-300, -400, and -500 series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007.

Subject

(d) Air Transport Association (ATA) of America Code 53: Fuselage.

Unsafe Condition

(e) This AD results from reports of cracking in the frame, or in the frame and frame reinforcement, common to the 1.04-inch nominal diameter wire penetration hole intended for wire routing. We are issuing this AD to detect and correct cracking in the fuselage frames and frame reinforcements, which could reduce the structural capability of the frames to sustain limit loads, and result in cracking in the fuselage skin and subsequent rapid depressurization of the airplane.

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 Requirements of AD 2009-02-06 With Clarifications of Compliance Requirements

Service Bulletin Reference Paragraph

(g) The term “service bulletin,” as used in this AD, means Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007.

(1) Where the service bulletin specifies a compliance time after the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.

(2) The “Condition” column of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007, refers to total flight cycles “at the date given on this service bulletin.” However, this AD applies to the airplanes with the specified total flight cycles as of April 15, 2009 (the effective date of AD 2009-02-06).

(3) Where the service bulletin specifies to contact Boeing for instructions for removing damage and repairing cracking: Before further flight, remove the damage or repair the cracking using a method approved in accordance with the procedures specified in paragraph (j) of this AD.

(4) Although the service bulletin referenced in this AD specifies to submit information to the manufacturer, this AD does not include that requirement.

Inspections, Related Investigative Actions, and Corrective Actions

(h) At the applicable time specified in paragraph 1.E., “Compliance,” of the service bulletin, except as specified by paragraph (g)(1) of this AD: Do a high frequency eddy current (HFEC) surface inspection or an HFEC hole/edge inspection for cracking of the 1.04-inch nominal diameter wire penetration hole in the frame and frame reinforcement, between stringer S-20 and S-21; and do all applicable related investigative and corrective actions by accomplishing all the actions specified in the Accomplishment Instructions of the service bulletin, except as specified by paragraphs (g)(3) and (g)(4) of this AD. Do all applicable related investigative and corrective actions before further flight. Thereafter, repeat the inspections at the applicable intervals specified in paragraph 1.E., “Compliance,” of the service bulletin.

Terminating Action

(i) Doing the repair in Part 3 or the preventative modification in Part 5 of the Accomplishment Instructions of the service bulletin terminates the repetitive inspection requirements of this AD.

Alternative Methods of Compliance (AMOCs)

(j)(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: Wayne Lockett, Aerospace Engineer, Airframe Branch, ANM-120S, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6447; fax (425) 917-6590. Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.

(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 an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who 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.

Material Incorporated by Reference

(k) You must use Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007, to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register previously approved the incorporation by reference of Boeing Alert Service Bulletin 737-53A1279, dated December 18, 2007, on April 15, 2009 (74 FR 10469, March 11, 2009).

(2) 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 206-544-5000, extension 1, fax 206-766-5680; e-mail me.boecom@boeing.com; Internet https://www.myboeingfleet.com.

(3) 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 or 425-227-1152.

(4) 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 .