2016-15291. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are superseding Airworthiness Directive (AD) 2012-12-04, for certain The Boeing Company Model 737-300, -400, and -500 series airplanes. AD 2012-12-04 required repetitive external detailed inspections and nondestructive inspections to detect cracks in the fuselage skin along the chem-mill steps at stringers S-1 and S-2R, between station (STA) 400 and STA 460, and repair if necessary. This new AD requires a preventive modification of the fuselage skin at crown stringers S-1 and S-2R. This new AD also reduces the inspection threshold for certain airplanes. This AD was prompted by a determination that, for certain airplanes, the skin pockets adjacent to the Air Traffic Control (ATC) antenna are susceptible to widespread fatigue damage. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin panels at the chem-mill steps, which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of the airplane.

DATES:

This AD is effective August 9, 2016.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of August 9, 2016.

The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of July 23, 2012 (77 FR 36134, June 18, 2012).

ADDRESSES:

For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone [phone], extension 1; fax [phone]; Internet https://www.myboeingfleet.com. You may view this referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221. It is also available on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2015-3628.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov. by searching for and locating Docket No. FAA-2015-3628; 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 Docket 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:

Jennifer Tsakoumakis, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 90712-4137; 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 2012-12-04, Amendment 39-17083 (77 FR 36134, June 18, 2012) (“AD 2012-12-04”). AD 2012-12-04 applied to certain The Boeing Company Model 737-300, -400, and -500 series airplanes. The NPRM published in the Federal Register on September 14, 2015 (80 FR 55045) (“the NPRM”). The NPRM was prompted by a determination that, for certain airplanes, the skin pockets adjacent to the ATC antenna are susceptible to widespread fatigue damage. The NPRM proposed to continue to require repetitive external detailed inspections and nondestructive inspections to detect cracks in the fuselage skin along the chem-mill steps at stringers S-1 and S-2R, between STA 400 and STA 460, and repair if necessary. The NPRM also proposed to require a preventive modification of the fuselage skin at crown stringers S-1 and S-2R. In addition, the NPRM proposed to revise certain compliance times. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin panels at the chem-mill steps, which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of the airplane.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

Requests To Clarify Compliance Time Changes

Boeing asked that we change the NPRM preamble, which stated that the proposed AD would reduce the inspection thresholds “and repetitive intervals” for certain airplanes. Boeing stated that the repetitive inspection intervals specified in Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, remain unchanged from the previous version of the service information, which was mandated by AD 2012-12-04. Boeing added that Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, reduced only the inspection threshold for those airplanes.

We agree with the commenter's request for the reason provided. We have changed the language in the SUMMARY of this final rule accordingly.

Request To Clarify Acceptable Previous Alternative Methods of Compliance (AMOCs)

Boeing and Southwest Airlines (SWA) asked that we revise paragraph (l)(4) of the proposed AD. Boeing requested that we state that AMOCs approved for AD 2012-12-04 are approved as AMOCs for “all corresponding requirements”—instead of just the requirements of paragraph (g)—of the proposed AD. Boeing stated that this proposed change matches the wording in paragraph (l)(4) of AD 2012-12-04. SWA added that paragraph (l)(4) of the proposed AD does not provide credit for AMOCs approved for the actions specified in paragraphs (f) and (g) of AD 2008-19-03, Amendment 39-15670 (73 FR 56958, October 1, 2008) (“AD 2008-19-03”). (AD 2008-19-03 was superseded by AD 2012-12-04.)

We agree to revise paragraph (n)(4) of this AD (paragraph (l)(4) of the proposed AD) to specify that AMOCs approved for AD 2012-12-04 are approved as AMOCs for all the corresponding provisions of this AD.

It is not necessary, however, to state that AMOCs approved for AD 2008-19-03 are approved for the requirements of this AD. When AD 2008-19-03 was superseded, the corresponding provisions of AD 2008-19-03 were retained in AD 2012-12-04. Therefore, no change to this final rule is necessary in this regard.

Request To Separate Certain Actions for Clarification

Boeing, ASL Airlines France, and SWA asked that we clarify the requirements of paragraph (h) of the proposed AD by separating the actions into two core paragraphs: One paragraph for “Repairs” and one paragraph for the “Preventive Modification.” Boeing stated that tables 1, 2, and 3 of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, address the repair and preventive modification instructions for Group 1 airplanes, and table 5 addresses repair instructions for Group 2 airplanes; therefore table 5 should not be included in paragraph (h)(2) of the proposed AD. Boeing also stated that Note (e) of tables 1, 2, and 3 of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, provides a terminating action provision for the repetitive inspections under the installed preventive modification doubler; therefore a terminating action should be added to paragraph (h)(2) of the proposed AD. ASL Airlines France stated that, as written, paragraph (h) of the proposed AD is confusing because it would require the preventive modification specified in paragraph (h)(2) of the proposed AD to be installed only if cracking is found. SWA stated that Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, does not provide repair instructions for cracks found in four or more tear strap bays and certain other conditions, as specified in figure 6 or figure 8 of the Accomplishment Instructions. SWA asked that a provision be added to paragraph (h)(2) of the proposed AD to allow for both new and existing repairs to remain on the airplane if the repair covers all eight chem-mill step inspection areas between STA 410 and STA 450, if approved by the FAA or a Boeing-approved representative.

We agree with the commenters' requests for the reasons provided. We have separated paragraph (h) of the proposed AD into paragraphs (h) and (i) of this AD to clarify the actions identified by the commenters (and have redesignated subsequent paragraphs accordingly).

Request To Add Exception for the Preventive Modification

Boeing asked that we add a new exception to address the preventive modification. Boeing stated that paragraph (j)(3) of the proposed AD addresses repairs, and a similar paragraph needs to be added to address the preventive modification specified in Part 9 of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015; Part 9 specifies contacting Boeing for preventive modification instructions. Boeing added that the new exception should be done using a method approved by the FAA or a Boeing approved representative.

We agree with the commenter's request. Part 9 of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specifies contacting Boeing for modification instructions if an existing repair is installed that was not accomplished in accordance with Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015. We have revised paragraph (l)(3) of this AD (paragraph (j)(3) of the proposed AD) to include the exception to account for the preventive modification.

Effect of Winglets on Accomplishment of the Proposed Actions

Aviation Partners Boeing stated that accomplishing the supplemental type certificate (STC) ST01219SE does not affect the actions specified in the NPRM.

We agree with the commenter. We have redesignated paragraph (c) of the proposed AD as (c)(1) and added new paragraph (c)(2) to this AD to state that installation of STC ST01219SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​BE866B732F6CF31086257B9700692796?​OpenDocument&​Highlight=​st01219se) does not affect the ability to accomplish the actions required by this final rule. Therefore, for airplanes on which STC ST01219SE is installed, a “change in product” AMOC approval request is not necessary to comply with the requirements of 14 CFR 39.17.

Request To Restate the Optional Modification in AD 2012-12-04

Boeing and Al Nippon Airways (ANA) asked that the optional modification specified in paragraph (i) of AD 2012-12-04 be restated in this AD. The commenters stated that Section 1.F., “Approval” of Boeing Alert Service Bulletin 737-53A1305, Revision 1, dated September 19, 2012, includes approval of the accomplishment of the inspections and modifications, in accordance with that service information for the modified area only, as a method of compliance with the modification specified in paragraph (i) of AD 2012-12-04. The commenters added that since the optional modification is not restated in the proposed AD, this approval is now eliminated.

We agree with the commenters for the reasons provided. We have restated the optional modification in new paragraph (j) of this AD (paragraph (i) of AD 2012-12-04), and redesignated subsequent paragraphs accordingly.

Request To Clarify the Extent of AMOC Approvals

Boeing asked whether AMOCs would be considered for “preventive modifications,” in addition to repairs, in paragraph (l)(3) of the proposed AD. Boeing stated that adding this would address the AMOC requirement for the mandatory preventive modification.

We agree with the commenter's request because deviations to the mandated preventive modification are possible. Therefore, we have added “modification” (as well as “alteration”) to paragraph (n)(3) of this AD (paragraph (l)(3) of the proposed AD).

Request To Clarify Exception

ASL Airlines France asked that we clarify the reference in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specified in the “Condition” columns. The commenter stated that the flight-cycle compliance time referred to in these columns specifies “at the Revision 3 date of this service bulletin” instead of “as of the effective date of this AD.” The commenter asked that we include a new paragraph to clarify that “as of the effective date of this AD” should be used for compliance throughout the proposed AD.

We acknowledge the commenter's concern; however, paragraph (l)(1) of the proposed AD already addressed this difference; paragraph (j)(2) of this AD retains this provision. Therefore, no change to this AD is necessary in this regard.

Request To Correct Typographical Errors

Boeing and ASL Airlines France asked that we correct the paragraph reference in Note 1 to paragraph (i) of the proposed AD and in paragraph (j)(3) of the proposed AD. The commenters stated that these are typographical errors.

The information in Note 1 to paragraph (i) of the proposed AD has been included in paragraph (j) of this final rule (paragraph (i) of the proposed AD), therefore “Note 1” no longer exists. In light of this, the requested correction is not necessary in this regard. We have corrected the reference in paragraph (j)(3) of the proposed AD (paragraph (l)(3) of this AD) accordingly.

Change to Paragraph (k) of This AD

We have revised the language in paragraph (k) of this AD (paragraph (i) in the proposed AD) to clarify that the post-repair/post-modification inspections are airworthiness limitations that are required by maintenance and operational rules; therefore, these inspections are not required by 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 changes described previously and minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM.

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

Related Service Information Under 1 CFR Part 51

We reviewed Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015. The service information describes procedures for repetitive external detailed inspections and non-destructive inspections to detect cracks in the fuselage skin along the chem-mill steps at stringers S-1 and S-2R, between STA 400 and STA 460, and repair of any cracking. The service information also describes procedures for a modification of the chem-mill steps at the locations identified, including related investigative actions and corrective actions, and repetitive post-mod inspections. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

Costs of Compliance

We estimate that this AD affects 186 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
Retained inspections from AD 2012-12-04	Between 7 and 15 work-hours × $85 per hour, depending on airplane configuration = between $595 and $1,275 per inspection cycle	$0	Between $595 and $1,275 per inspection cycle	Between $110,670 and $237,150 per inspection cycle.
New modification	236 work-hours × $85 per hour = $20,060	1	$20,060	$3,731,160.
1 We currently have no specific cost estimates associated with the parts necessary for the modification. We cannot determine the cost of the materials because the modification parts must be sized at the time the modification is installed, taking into account any existing repairs in the area.

We have received no definitive data that enables 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) 2012-12-04, Amendment 39-17083 ( 77 FR 36134, June 18, 2012), and adding the following new AD:

2016-13-10 The Boeing Company: Amendment 39-18574; Docket No. FAA-2015-3628; Directorate Identifier 2015-NM-025-AD.

(a) Effective Date

This AD is effective August 9, 2016.

(b) Affected ADs

This AD replaces AD 2012-12-04, Amendment 39-17083 (77 FR 36134, June 18, 2012) (“AD 2012-12-04”).

(c) Applicability

(1) This AD applies to The Boeing Company Model 737-300, -400, and -500 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015.

(2) Installation of Supplemental Type Certificate (STC) ST01219SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​BE866B732F6CF31086257B9700692796?​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

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

(e) Unsafe Condition

This AD was prompted by reports of cracks found on the fuselage skin at the chem-mill steps, and the determination that, for certain airplanes, the skin pockets adjacent to the Air Traffic Control antenna are susceptible to widespread fatigue damage. We are issuing this AD to detect and correct fatigue cracking of the fuselage skin panels at the chem-mill steps, which could result in sudden fracture and failure of the fuselage skin panels, and consequent rapid decompression of the airplane.

(f) Compliance

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

(g) Inspections

At the applicable time specified in tables 1, 2, 3, and 5 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, except as required by paragraphs (l)(1) and (l)(2) of this AD: Do the actions specified in paragraphs (g)(1) and (g)(2) of this AD, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, except as required by paragraph (l)(3) of this AD. Repeat the applicable inspections thereafter at the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015.

(1) Do an external detailed inspection for cracking of the fuselage skin chem-mill steps.

(2) Do an external non-destructive (medium frequency eddy current, magneto optical imaging, C-Scan, or ultrasonic phased array) inspection for cracking of the fuselage skin chem-mill steps.

(h) Repair

If any cracking is found during any inspection required by paragraph (g) of this AD, do the applicable actions specified in paragraph (h)(1), (h)(2), or (h)(3) of this AD.

(1) Repair before further flight in accordance with Part 2 (for Group 1 airplanes) or Part 7 (for Group 2 airplanes) of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015; except as required by paragraph (l)(3) of this AD. Installation of a repair that meets the conditions specified in Note (a) of table 1, 2, 3, or 5 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, terminates the repetitive inspections required by paragraph (g) of this AD for the area covered by that repair only.

(2) For Group 1 airplanes: Accomplishing the modification specified in paragraph (i) of this AD is a method of compliance with paragraph (h)(1) of this AD.

(3) If any cracking is found in any area not covered by the preventive modification doubler during any inspection required by paragraph (g) of this AD: Repair before further flight, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, except as provided by paragraph (n)(4) of this AD. Both new and existing repairs are allowed if the repair covers all eight chem-mill step inspection areas between STA 410 and STA 450, and the repairs were done using a method approved in accordance with the procedures specified in paragraph (n)(1) of this AD.

(i) Preventive Modification

For Group 1 airplanes: At the applicable time specified in tables 1, 2 and 3 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, except as required by paragraphs (l)(1) and (l)(2) of this AD, do a preventive modification of the fuselage skin at crown stringers S-1 and S-2R, including all applicable related investigative actions in accordance with Part 9 of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, except as provided by paragraph (n)(4) of this AD. Do all applicable related investigative actions concurrently with the modification. Installation of a preventive modification terminates the repetitive inspections required by paragraph (g) of this AD for the modified area only. Thereafter, repeat the inspections specified in Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015.

(j) Optional Modification

Accomplishing a modification of the chem-mill steps at any location identified in Boeing Service Bulletin 737-53A1293, Revision 2, dated August 10, 2011, using a method approved in accordance with the procedures specified in paragraph (n)(1) of this AD, terminates the repetitive inspections required by paragraph (g) of this AD for the modified area only.

(k) Post-Repair/Post-Modification Inspections

Tables 4 and 6 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specify post-repair/post-modification airworthiness limitation inspections in compliance with 14 CFR 25.571(a)(3) at the modified locations, which support compliance with 14 CFR 121.1109(c)(2) or 129.109(b)(2). As airworthiness limitations, these inspections are required by maintenance and operational rules. It is therefore unnecessary to mandate them in this AD. Deviations from these inspections require FAA approval, but do not require an alternative method of compliance.

(l) Exceptions to Service Bulletin Specifications

(1) Where Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specifies a compliance time “after the Revision 3 date of this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.

(2) Where the Condition column of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specifies a condition based on when an airplane has or has not been inspected, this AD bases the condition on whether an airplane has or has not been inspected on the effective date of this AD.

(3) Where Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015, specifies to contact Boeing for repair or preventive modification instructions: Before further flight, do the repair or preventive modification, as applicable, using a method approved in accordance with the procedures specified in paragraph (n)(1) of this AD.

(m) Credit for Previous Actions

(1) This paragraph provides credit for actions required by paragraphs (g) and (h) of this AD, if those actions were performed before July 23, 2012 (the effective date of AD 2012-12-04), using Boeing Alert Service Bulletin 737-53A1293, Revision 1, dated July 7, 2010, which is not incorporated by reference in this AD.

(2) This paragraph provides credit for actions required by paragraphs (g) and (h) of this AD, if those actions were performed before the effective date of this AD using Boeing Alert Service Bulletin 737-53A1293, Revision 2, dated August 10, 2011, which was incorporated by reference in AD 2012-12-04.

(n) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Los Angeles 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 paragraph (o)(1) 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, modification, or alteration required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Los Angeles ACO, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation method must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(4) AMOCs approved for AD 2012-12-04 are approved as AMOCs for the corresponding provisions of this AD.

(o) Related Information

(1) For more information about this AD, contact Jennifer Tsakoumakis, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: [phone]; fax: [phone]; email: [e-mail].

(2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (p)(5) and (p)(6) of this AD.

(p) 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.

(3) The following service information was approved for IBR on August 9, 2016.

(i) Boeing Alert Service Bulletin 737-53A1293, Revision 3, dated January 23, 2015.

(ii) Reserved.

(4) The following service information was approved for IBR on July 23, 2012 (77 FR 36134, June 18, 2012).

(i) Boeing Service Bulletin 737-53A1293, Revision 2, dated August 10, 2011.

(ii) Reserved.

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

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

(7) 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 June 21, 2016.

Dorr Anderson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.