2013-09205. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900 and -900ER series airplanes. This AD was prompted by a report of leaking fuel from the wing leading edge area at the inboard end of the number 5 leading edge slat. This AD requires modifying the fluid drain path in the wing leading edge area, forward of the wing front spar, and doing all applicable related investigative and corrective actions; and installing new seal disks on the latches in the fuel shutoff valve access door. We are issuing this AD to prevent flammable fluids from accumulating in the wing leading edge, and draining inboard and onto the engine exhaust nozzle, which could result in a fire.

DATES:

This AD is effective June 5, 2013.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of June 5, 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:

Ansel James, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

 

Discussion

We issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to the specified products. That SNPRM published in the Federal Register on March 16, 2012 (77 FR 15638). The original NPRM (74 FR 15683, April 7, 2009) proposed to require modifying the fluid drain path in the wing leading edge area, forward of the wing front spar and doing all applicable related investigative and corrective actions. The SNPRM proposed to revise that NPRM by including installing new seal disks on the latches in the fuel shutoff valve access door as part of the modification and by specifying that certain inspections are detailed inspections. The SNPRM also proposed to revise the applicability to include additional airplanes.

Revised Service Bulletin

Boeing has issued Special Attention Service Bulletin 737-57-1293, Revision 3, dated December 14, 2012. This revision includes clarification for the re-identification of parts and assemblies. We have revised paragraphs (c) and (g) of this AD to refer to Boeing Special Attention Service Bulletin 737-57-1293, Revision 3, dated December 14, 2012.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the supplemental NPRM (77 FR 15638, March 16, 2012) and the FAA's response to each comment.

Concurrence

Boeing concurred with the content of the SNPRM (77 FR 15638, March 16, 2012).

Request for Compliance Time Extension

United Airlines, Tracinda Flight Department, and American Airlines requested an extension to the 24-month compliance time specified in the SNPRM (77 FR 15638, March 16, 2012). Tracinda Flight Department requested a compliance time of 36 months to coincide with a heavy maintenance check. American Airlines requested a compliance time of 60 to 72 months to coincide with its scheduled heavy maintenance check. American Airlines stated that the actions accomplished in accordance with AD 2011-06-05, Amendment 39-16629 (76 FR 15808, March 22, 2011), address the safety issue identified in the SNPRM. United Airlines recommended a compliance time of 60 months for airplanes on which actions have been done in accordance with AD 2011-06-05, as well as airplanes having line numbers 2700 and subsequent on which the actions have been incorporated for the wing slat down stop hardware modification and inspections.

We disagree with the commenters' requests to extend the compliance time. We have determined that the compliance time, as proposed, represents the maximum interval of time allowable for the affected airplanes to continue to safely operate before the modification is done. Since maintenance schedules vary among operators, there would be no assurance that the airplanes would be modified during that maximum interval. However, under the provisions of paragraph (i) of the final rule, we will consider requests for approval of an extension of the compliance time if sufficient data are submitted to substantiate that a new compliance time would provide an acceptable level of safety. Additionally, the issue addressed in this AD is different from the issue addressed in AD 2011-06-05, Amendment 39-16629 (76 FR 15808, March 22, 2011); therefore, changing the compliance time based on the actions done in accordance with AD 2011-06-05 is not acceptable. We have not changed the AD in this regard.

Request for Change to Airplane Groups

Southwest Airlines requested a change to the airplanes in Group 2, as specified in Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011. The commenter stated that Group 2 airplanes include line numbers 2131 through 2837—instead of 2131 through 2437, as specified in Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011. The commenter stated that Figures 4 and 16 of that service bulletin specify a modification of the hinge assembly having part number (P/N) 116A5522-1, which is installed on airplanes having line numbers 1 through 2837.

We disagree to change the airplanes in Group 2. The purpose of the Group 2 division is to address a parting agent issue and not hinge trimming. Although the hinge assembly part number does change at airplane line number 2837, it is unrelated to the Group 2 division. No change has been made to the AD in this regard.

Request for Parts Specifications

American Airlines requested that we provide material specifications and part dimensions to allow for manufacturing of alternatives for a seal disk having P/N 116A8505-2. The commenter stated that the parts are unavailable from Boeing and having an alternate part is necessary to ensure a sufficient supply for operators.

We cannot include proprietary information such as part dimensions and materials in ADs; however, we are aware that seal disks having P/N 116A8505-2 are now available from the manufacturer. No change has been made to the AD in this regard.

Request for Credit for Actions Done Previously

Tracinda Flight Department requested that we revise the supplemental NPRM (77 FR 15638, March 16, 2012) to provide credit for doing the actions specified in Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011.

We agree to allow credit for actions done in accordance with Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011. We have added new paragraph (h) to this AD accordingly.

American Airlines requested that we revise the supplemental NPRM (77 FR 15638, March 16, 2012) to allow credit for actions done using Boeing Special Attention Service Bulletin 737-57-1293, Revision 1, dated January 11, 2010. The commenter stated that the updates in Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011, do not address the safety issue with the exception of the addition of the rubber seal disk.

We disagree with the commenter's request. Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011, changed the inspection type for the bonding jumper countersink diameter and clarified certain instructions specified in Boeing Special Attention Service Bulletin 737-57-1293, Revision 1, dated January 11, 2010. However, operators may request approval of an alternative method of compliance (AMOC), as specified in paragraph (i) of this AD. No change has been made to the AD in this regard.

Conclusion

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

• Are consistent with the intent that was proposed in the SNPRM (77 FR 15638, March 16, 2012) for correcting the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the SNPRM (77 FR 15638, March 16, 2012).

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

Costs of Compliance

We estimate that this AD affects 1,072 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
Modification, Group 1 (734 airplanes)	50 work-hours × $85 per hour = $4,250	$1,262	$5,512	$4,045,808
Modification, Group 2 (58 airplanes)	27 work-hours × $85 per hour = $2,295	1,262	3,557	206,306
Modification, Group 3 (280 airplanes)	3 work-hours × $85 per hour = $255	94	349	97,720

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),

(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 adding the following new airworthiness directive (AD):

2013-08-18 The Boeing Company: Amendment 39-17435; Docket No. FAA-2009-0288; Directorate Identifier 2008-NM-214-AD.

(a) Effective Date

This AD is effective June 5, 2013.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, -900 and -900ER series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-57-1293, Revision 3, dated December 14, 2012.

(d) Subject

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

(e) Unsafe Condition

This AD was prompted by a report of leaking fuel from the wing leading edge area at the inboard end of the number 5 leading edge slat. We are issuing this AD to prevent flammable fluids from accumulating in the wing leading edge, and draining inboard and onto the engine exhaust nozzle, which could result in a fire.

(f) Compliance

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

(g) Modification

Within 24 months after the effective date of this AD, modify the fluid drain path in the wing leading edge area, forward of the wing front spar, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-57-1293, Revision 3, dated December 14, 2012. Do all applicable related investigative and corrective actions before further flight.

(h) Credit for Previous Actions

This paragraph provides credit for the corresponding actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Boeing Special Attention Service Bulletin 737-57-1293, Revision 2, dated September 28, 2011, which is not incorporated by reference in this AD.

(i) 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.

(j) Related Information

For more information about this AD, contact Ansel James, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

(k) 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 the AD specifies otherwise.

(i) Boeing Special Attention Service Bulletin 737-57-1293, Revision 3, dated December 14, 2012.

(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 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.

(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 April 5, 2013.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.