2013-19811. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are superseding airworthiness directive (AD) 2008-06-29, which applied to all The Boeing Company Model 737-300, -400, and -500 series airplanes. AD 2008-06-29 required repetitive inspections of the downstop assemblies on the main tracks of the No. 2, 3, 4, and No. 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or in the wrong order; other specified actions; and related investigative and corrective actions if necessary. This new AD retains these requirements and adds an inspection of the slat can interior for foreign object debris (FOD), and removal of any FOD found; modification of the slat track hardware; an inspection for FOD and for damage to the interior surface of the slat cans; and related investigative and corrective actions, if necessary. This AD was prompted by development of a modification by the manufacturer, which, when installed, would terminate the repetitive inspections. We are issuing this AD to prevent loose or missing parts in the main slat track downstop assemblies, which could puncture the slat track housing and result in a fuel leak and consequent fire.

DATES:

This AD is effective September 20, 2013.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of September 20, 2013.

ADDRESSES:

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]; Internet https://www.myboeingfleet.com. You may review copies of the referenced 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.

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 address for the Docket Office (phone: [phone]) is Document Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

 

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008) (“AD 2008-06-29”). AD 2008-06-29 applied to the specified products. The NPRM published in the Federal Register on March 11, 2013 (78 FR 15332). The NPRM proposed to continue to require repetitive inspections of the downstop assemblies on the main tracks of the No. 2, 3, 4, and No. 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or in the wrong order; other specified actions; and related investigative and corrective actions if necessary. The NPRM also proposed to add an inspection of the slat can interior for foreign object debris (FOD), and removal of any FOD found; modification of the slat track hardware; an inspection for FOD and for damage to the interior surface of the slat cans; and related investigative and corrective actions, if necessary.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal (78 FR 15332, March 11, 2013) and the FAA's response to each comment.

Concurrence With NPRM (78 FR 15332, March 11, 2013)

Boeing stated that it concurs with the content of the proposed rule (78 FR 15332, March 11, 2013).

Statement Regarding Installation of Winglets

Aviation Partners Boeing (APB) stated that the installation of winglets per STC ST01219SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​2C6E3DBDDD36F91C862576A4005D64E2?​OpenDocument&​Highlight=​st01219se) does not affect the actions specified in the NPRM (78 FR 15332, March 11, 2013).

We concur. We have added new paragraph (c)(2) to this AD, which states that STC ST01219SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​2C6E3DBDDD36F91C862576A4005D64E2?​OpenDocument&​Highlight=​st01219se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of Section 39.17 of the Federal Aviation Regulations (14 CFR 39.17). For all other AMOC requests, the operator must request approval of an AMOC in accordance with the procedures specified in paragraph (k) of this AD.

Conclusion

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the change described previously—and minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM (78 FR 15332, March 11, 2013) for correcting the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM (78 FR 15332, March 11, 2013).

We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.

Costs of Compliance

We estimate that this AD affects 568 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

Estimated costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Inspection of slat track housing [retained actions from AD 2008-06-29 (73 FR 15397, March 24, 2008)]	4 work-hours × $85 per hour = $340 per inspection cycle	$0	$340	$193,120
One-time detailed inspection of slat can [new action]	5 work-hours × $85 per hour = $85	0	425	241,400
Installation of modification [new action]	12 work-hours × $85 per hour = $1,020	3,124	4,144	2,353,792

We have received no definitive data that would enable us to provide a cost estimate for the on-condition actions specified in 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 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing airworthiness directive (AD) 2008-06-29, Amendment 39-15441 ( 73 FR 15397, March 24, 2008), and adding the following new AD:

2013-15-14 The Boeing Company: Amendment 39-17530; Docket No. FAA-2013-0207; Directorate Identifier 2011-NM-071-AD.

(a) Effective Date

This AD is effective September 20, 2013.

(b) Affected ADs

This AD supersedes AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008).

(c) Applicability

(1) This AD applies to all The Boeing Company Model 737-300, -400, and -500 series airplanes, certificated in any category.

(2) Installation of Supplemental Type Certificate (STC) ST01219SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​2C6E3DBDDD36F91C862576A4005D64E2?​OpenDocument&​Highlight=​st01219se) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57: Wings.

(e) Unsafe Condition

This AD was prompted by reports of fuel leaking from a puncture in the slat track housing (referred to as “slat can”). We are issuing this AD to prevent loose or missing parts in the main slat track downstop assemblies, which could puncture the slat track housing and result in a fuel leak and consequent fire.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Retained Inspection of Downstop Assemblies and Corrective Action

This paragraph restates the requirements of paragraph (f) of AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), with revised service information. At the applicable times specified in Table 1 of paragraph 1.E. of Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; except as provided by paragraph (g)(1) of this AD: Do a detailed inspection or borescope inspection of the downstop assemblies on the main tracks of the No. 2, 3, 4, and 5 slats and the inboard track of the No. 1 and 6 slats to verify if any parts are missing, damaged, or installed in the wrong order; and do all the other specified, related investigative, and corrective actions as applicable; by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; except as provided by paragraphs (g)(2) and (g)(3) of this AD. Repeat the inspection thereafter at the applicable times specified in Table 1 of paragraph 1.E. of Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. Do all applicable related investigative and corrective actions before further flight. As of the effective date of this AD, only Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, may be used to accomplish the actions required by this paragraph.

(1) Where Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008, or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, specifies counting the compliance time from “the date on the service bulletin,” this AD requires counting the compliance time from April 8, 2008 (the effective date of AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008)).

(2) For airplanes on which any downstop assembly part is missing or damaged, a borescope inspection of the inside of the slat track housing for loose parts and damage to the wall of the slat track housing may be accomplished in lieu of the detailed inspection of the inside of the slat track housing that is specified in Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. As of the effective date of this AD, only Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, may be used to do the actions specified in this paragraph.

(3) If any damaged slat track housing is found during any inspection required by paragraph (g) of this AD: Before further flight, repair in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; replace the slat can with a new slat can having the same part number, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; or repair the slat can using a method approved in accordance with the procedures specified in paragraph (k) of this AD.

(h) New Detailed Inspection for Foreign Object Debris (FOD)

Within 24 months after the effective date of this AD, do a one-time detailed inspection of the slat can interior to detect FOD, in accordance with Part III of the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. If any FOD is found, before further flight, remove it, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011.

(i) New Modification and Inspection

Within 72 months or 15,000 flight cycles, whichever occurs first, after the effective date of this AD: Modify the slat track hardware by installing new downstop assembly hardware, and do a detailed inspection for FOD and a one-time inspection for damage to the interior surface of the slat can for the inboard and outboard tracks of slats 2 through 5, and the inboard slats of tracks 1 and 6; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011. Do all applicable related investigative and corrective actions before further flight. Accomplishment of the actions required by this paragraph terminates the inspections required by paragraphs (g) and (h) of this AD.

(j) Credit for Previous Actions

This paragraph provides credit for the actions required by paragraphs (g), (h), and (i) of this AD, if those actions were performed before the effective date of this AD using Boeing Alert Service Bulletin 737-57A1301, Revision 1, dated September 24, 2009; or Boeing Alert Service Bulletin 737-57A1301, Revision 2, dated January 17, 2011; which are not incorporated by reference in this AD.

(k) Alternative Methods of Compliance (AMOCs)

(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. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: [e-mail].

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(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 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), are approved as AMOCs for the corresponding provisions of this AD.

(l) Related Information

For more information about this AD, contact Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

(m) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.

(i) Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011.

(ii) Reserved.

(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]; Internet https://www.myboeingfleet.com.

(4) You may view this service information at 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 view this 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/​cfr/​ibr-locations.html.

Issued in Renton, Washington, on July 21, 2013.

Stephen P. Boyd,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.