2018-07638. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are superseding Airworthiness Directive (AD) 2014-03-07, which applied to certain The Boeing Company Model MD-11 and MD-11F airplanes. AD 2014-03-07 required inspecting certain locations of the wire bundles of the center upper auxiliary fuel tank for damage, and corrective action if necessary. AD 2014-03-07 also required installing nonmetallic barrier/shield sleeving, new clamps, new attaching hardware, and a new extruded channel. This AD adds certain inspections and expands the applicability. This AD was prompted by the determination that it is necessary to require an inspection of the wire bundles for damage at certain center upper auxiliary fuel tank locations on certain airplanes. We are issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective May 21, 2018.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 21, 2018.

The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of March 26, 2014 (79 FR 9392, February 19, 2014).

The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of February 4, 2010 (74 FR 69249, December 31, 2009).

ADDRESSES:

For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; telephone [phone]; internet https://www.myboeingfleet.com. You may view this service information at the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0770.

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-2017-0770; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, the regulatory evaluation, any comments received, and other information. The address for Docket Operations (phone: [phone]) is Docket Operations, 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:

Samuel Lee, Aerospace Engineer, Propulsion Section, FAA, Los Angeles ACO Branch, 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 2014-03-07, Amendment 39-17744 (79 FR 9392, February 19, 2014) (“AD 2014-03-07”). AD 2014-03-07 applied to certain The Boeing Company Model MD-11 and MD-11F airplanes. The NPRM published in the Federal Register on August 17, 2017 (82 FR 39062). The NPRM was prompted by the determination that it is necessary to require an inspection of the wire bundles for damage at certain center upper auxiliary fuel tank locations on certain airplanes. The NPRM proposed to continue to require inspecting certain locations of the wire bundles of the center upper auxiliary fuel tank for damage, and corrective action if necessary. The NPRM also proposed to continue to require installing nonmetallic barrier/shield sleeving, new clamps, new attaching hardware, and a new extruded channel. The NPRM proposed to add certain inspections and expand the applicability. We are issuing this AD to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss 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.

Supportive Comments

The Air Line Pilots Association, International and Boeing supported the content of the NPRM.

Request To Clarify NPRM Requirements

FedEx Express (FedEx) asked that the requirements in the NPRM relative to the referenced service information be clarified. FedEx stated that Boeing Service Bulletin MD11-28-126 has been revised 6 times, and its related AD has been superseded twice; therefore, the NPRM requirements are confusing. FedEx added that the NPRM might need to be re-written completely to clearly state what the new requirements are, since some operators have accomplished either the original issue or one or more of Revisions 1 through 5 of Boeing Service Bulletin MD11-28-126. FedEx stated that it has accomplished Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011; and at the time those procedures were done, the FedEx fleet was classified as Group 1, Configuration 1, and Group 2, Configuration 1 airplanes because FedEx didn't accomplish prior revisions of the service information. FedEx noted that currently its airplanes are Group 1, Configuration 2, and Group 2, Configuration 2, because FedEx has accomplished prior revisions of Boeing Service Bulletin MD11-28-126 on its airplanes.

We acknowledge the commenter's request and agree to clarify. The new requirements of this AD apply only to certain airplanes identified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. As noted by the commenter, for a given airplane, the group and configuration might have changed between Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011, and Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016.

Group 1, Configuration 1 airplanes in Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011, are defined as airplanes on which “prior issues of this service bulletin” have not been accomplished. If the actions specified in Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011, have been done on one of these airplanes, this airplane becomes a Group 1 Configuration 2 airplane as defined in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, (airplanes on which “prior issues of this service bulletin” have been accomplished). Therefore, for this airplane, the inspections specified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, for its new configuration must be done.

The inspections in paragraph (i) of this AD must be done for airplanes identified as Groups 1, 2, and 5, Configuration 2 airplanes in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. For this configuration, Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, adds certain work instructions that were not in Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011; or Boeing Service Bulletin MD11-28-126, Revision 5, dated July 29, 2014. Therefore, we have not changed this AD in this regard.

Request To Clarify New Inspection Requirements

FedEx asked that the new inspection requirements specified in the proposed AD be clarified. FedEx stated that the proposed AD would retain all requirements of AD 2014-03-07, and would add inspection requirements for certain airplanes, as well as expanding the applicability. FedEx noted that Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, adds new inspection requirements but does not specify that the inspection be done at additional locations, as indicated in the proposed AD. FedEx added that the work instructions specified in Revisions 4 and 6 of Boeing Service Bulletin MD11-28-126 are for the same area, so it is not clear which additional locations are mandated by the proposed AD.

We agree to clarify. Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, adds an inspection to determine if the wire bundles routed above the center upper auxiliary fuel tank between floor beams touch the upper surface of the tank for Groups 1, 2, and 5, Configuration 2 airplanes. We acknowledge that the phrase “additional locations” is unclear, and we have revised paragraph (i)(1) of this AD to state “Do a general visual inspection of the wire bundles at the applicable center upper auxiliary fuel tank locations . . .” Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, identifies the applicable inspection areas.

Request To Specify Airplane Configuration

FedEx asked that the airplane configurations specified in the proposed AD be clarified. FedEx stated that paragraph (i) of the proposed AD specifies the following: “For Groups 1, 2, and 5 Configuration 2 airplanes, as identified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016.” FedEx added that, as defined in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, the FedEx fleet will be Group 1, Configuration 2 and Group 2, Configuration 2 airplanes because FedEx has accomplished a prior revision of this service information. FedEx believes its fleet should be in Group 1, Configuration 1, and Group 2, Configuration 1, but stated that it is not clear which airplanes are in which groups and configurations.

We acknowledge the commenter's request and provide the following clarification. Paragraph 1.A., “Effectivity” of Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, specifies that airplanes on which previous issues of the service information have been done are identified as Configuration 2 airplanes. Therefore, any airplanes on which any previous issue of the service information was accomplished would be classified as Configuration 2. We have not changed this AD in this regard.

Request for Credit for Previous Actions Accomplished

FedEx and United Parcel Service (UPS) requested credit for previous accomplishment of the actions in paragraphs (i)(1) and (i)(2) of the proposed AD using Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011.

FedEx stated that new inspections and corrective actions as specified in paragraphs (i)(1) and (i)(2) of the proposed AD were already performed by FedEx per Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011, and should not be performed again. FedEx believes the proposed AD should give credit for work accomplished under Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011.

UPS stated that prior accomplishment of Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011, for Groups 1 and 2, Configuration 1 freighter aircraft meets the requirements of Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. UPS stated that the additional steps added by Revisions 5 and 6 of Boeing Service Bulletin MD11-28-126 are not applicable to airplanes in freighter configurations or have already been accomplished using Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011. UPS added that no further actions should be required on those airplanes.

We agree to clarify. As stated previously, Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, adds an inspection to determine if the wire bundles routed above the center upper auxiliary fuel tank between floor beams touch the upper surface of the tank for Groups 1, 2, and 5, Configuration 2 airplanes. This inspection was not included in Boeing Service Bulletin MD11-28-126, Revision 5, dated July 29, 2014; nor any of the previous revisions of Boeing Service Bulletin MD11-28-126. In addition, for compliance with this AD, this inspection must be done before the detailed inspection specified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, for Groups 1, 2, and 5, Configuration 2 airplanes. However, under the provisions of paragraph (m) of this AD, we will consider requests for approval of alternative methods of compliance (AMOCs) if sufficient data are submitted to substantiate that the actions would provide an acceptable level of safety. We have not changed this AD in this regard.

We also partially agree with the commenter. The new requirements in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, do not apply to certain freighter airplanes. Freighter airplanes are included in the procedures for Groups 1 and 5, Configuration 2 airplanes, but not for Group 2, Configuration 2 airplanes, as specified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. Only passenger airplanes are included in the procedures for Group 2, Configuration 2 airplanes in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. Therefore, we have added “as applicable” to the introductory text to paragraph (i) of this AD to clarify that the actions in paragraphs (i)(1) and (i)(2) of this AD apply to Groups 1 and 5, Configuration 2 airplanes, and passenger airplanes in Group 2, Configuration 2.

Conclusion

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD as proposed, except for minor editorial changes. We have determined that these minor changes:

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

Related Service Information Under 1 CFR Part 51

We reviewed Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016. This service information describes procedures for inspecting certain wire bundles of the center auxiliary fuel tank for damage, and repairing or replacing damaged wires. This service information also describes procedures for installing barrier/shield sleeving, clamping, and an extruded channel. 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 125 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/installation [retained actions from AD 2009-26-16, Amendment 39-16155 (74 FR 69249, December 31, 2009)]	168 to 182 work-hours × $85 per hour = $14,280 to $15,470 per inspection cycle	$15,708 to $28,005	$29,988 to $43,475 per inspection cycle	$3,748,500 to $5,434,375 per inspection cycle.
Inspection/installation for Groups 1, 2, and 5, all Configuration 2 airplanes (retained actions from AD 2014-03-07)	Up to 9 work-hours × $85 per hour = $765	$6,166	Up to $6,931	Up to $866,375.
Inspection/installation for Groups 1, 2, and 5, all Configuration 2 airplanes (new action)	Up to 4 work-hours × $85 per hour = $340	$0	Up to $340	Up to $42,500.
Inspection/installation for Line Number 579 (new action)	4 work-hours × $85 per hour = $340	$28,005	$340	$28,345.

We have received no definitive data that enables us to provide cost estimates 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.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes and associated appliances to the Director of the System Oversight Division.

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) 2014-03-07, Amendment 39-17744 ( 79 FR 9392, February 19, 2014), and adding the following new AD:

2018-07-20 The Boeing Company: Amendment 39-19251; Docket No. FAA-2017-0770; Product Identifier 2017-NM-030-AD.

(a) Effective Date

This AD is effective May 21, 2018.

(b) Affected ADs

This AD replaces AD 2014-03-07, Amendment 39-17744 (79 FR 9392, February 19, 2014) (“AD 2014-03-07”).

(c) Applicability

This AD applies to The Boeing Company Model MD-11 and MD-11F airplanes, certificated in any category, as identified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016.

(d) Subject

Air Transport Association (ATA) of America Code 28, Fuel.

(e) Unsafe Condition

This AD was prompted by fuel system reviews conducted by the manufacturer that indicated the need to inspect wire bundles at certain locations of the center upper auxiliary fuel tanks in addition to inspection locations required by AD 2014-03-07. We are issuing this AD to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

(f) Compliance

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

(g) Retained Inspection and Corrective Action, With Revised Service Information

This paragraph restates the requirements of paragraph (g) of AD 2014-03-07, with revised service information. For airplanes identified in Boeing Service Bulletin MD11-28-126, Revision 1, dated June 18, 2009: Within 60 months after February 4, 2010 (the effective date of AD 2009-26-16, Amendment 39-16155 (74 FR 69249, December 31, 2009)), do the actions specified in paragraphs (g)(1) through (g)(5) of this AD, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD11-28-126, Revision 1, dated June 18, 2009; Revision 4, dated November 29, 2011; or Revision 6, dated July 1, 2016; except as required by paragraph (k) of this AD. As of the effective date of this AD, only Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, may be used to accomplish the actions required by this paragraph. Do all applicable corrective actions before further flight.

(1) Do a general visual inspection of the wire bundles between Stations 1238.950 and 1361.000 to determine if wires touch the upper surface of the center upper auxiliary fuel tank, and mark the location, as applicable.

(2) Do a detailed inspection for splices and damage of all wire bundles above the center upper auxiliary fuel tank between Stations 1218.950 and 1381.000.

(3) Do a detailed inspection for damage (burn marks) of the upper surface of the center upper auxiliary fuel tank.

(4) Do a detailed inspection for damage (burn marks) on the fuel vapor barrier seal.

(5) Install a nonmetallic barrier/shield sleeving, new clamps, new attaching hardware, and a new extruded channel.

(h) Retained Additional Inspections and Corrective Action, With Revised Service Information

This paragraph restates the requirements of paragraph (h) of AD 2014-03-07, with revised service information. For airplanes in Group 1, Configuration 2; Group 2, Configuration 2; and Group 5, Configuration 2; as identified in Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011: Within 60 months after March 26, 2014 (the effective date of AD 2014-03-07), do a detailed inspection of wire bundles for splices and damage (chafing, arcing, and broken insulation) and damage (burn marks) on the upper surface of the center upper auxiliary fuel tank and fuel vapor barrier seal; install barrier/shield sleeving and clamping; and do all applicable corrective actions at the applicable locations specified in paragraphs (h)(1) through (h)(3) of this AD, in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011; or Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016; except as required by paragraph (k) of this AD. As of the effective date of this AD, only Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, may be used to accomplish the actions required by this paragraph. Do all applicable corrective actions before further flight.

(1) For Group 1, Configuration 2 airplanes, between Stations 1238.950 and 1381.000, Stations 1238.950 and 1256.000, and Stations 1238.950 and 1256.800, depending on passenger or freighter configuration.

(2) For Group 2, Configuration 2 airplanes, between Stations 1238.950 and 1275.250, and Stations 1238.950 and 1275.250, passenger configuration only.

(3) For Group 5, Configuration 2 airplanes, between Stations 1381.000 and 1238.950.

(i) New Inspections and Corrective Actions for Certain Airplanes

For Groups 1, 2, and 5 Configuration 2 airplanes, as identified in Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016: Within 60 months after the effective date of this AD, do the actions required by paragraphs (i)(1) and (i)(2) of this AD, as applicable, in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016.

(1) Do a general visual inspection of the wire bundles at the applicable center upper auxiliary fuel tank locations to determine if wires touch the upper surface of the fuel tank, and mark the location as applicable.

(2) Do a detailed inspection of the wire bundles for splices and damage on the upper surface of the center upper auxiliary fuel tank and fuel vapor barrier seal; install barrier/shield sleeving, clamping, and extruded channels, as applicable; and do all applicable corrective actions before further flight; except as required by paragraph (k) of this AD.

(j) New Requirements for Line Number 579

For airplane Line Number 579: Within 60 months after the effective date of this AD, do the actions specified in paragraphs (g)(1) through (g)(5) of this AD, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016, except as required by paragraph (k) of this AD. Do all applicable corrective actions before further flight.

(k) Exception to Service Information Specifications

Where Boeing Service Bulletin MD11-28-126, Revision 1, dated June 18, 2009; Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011; or Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016; specifies to contact The Boeing Company for repair instructions: Before further flight, repair the auxiliary fuel tank using a method approved in accordance with the procedures specified in paragraph (m) of this AD.

(l) Credit for Previous Actions

(1) This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before March 26, 2014 (the effective date of AD 2014-03-07), using the service information specified in paragraph (l)(1)(i) or (l)(1)(ii) of this AD.

(i) Boeing Service Bulletin MD11-28-126, Revision 2, dated November 18, 2010.

(ii) Boeing Service Bulletin MD11-28-126, Revision 3, dated June 3, 2011.

(2) This paragraph provides credit for actions required by paragraph (h) of this AD, if those actions were performed before March 26, 2014 (the effective date of AD 2014-03-07), using Boeing Service Bulletin MD11-28-126, Revision 3, dated June 3, 2011.

(m) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Los Angeles ACO Branch, 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 certification office, send it to the attention of the person identified in paragraph (n)(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 Branch, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(4) AMOCs approved previously for AD 2014-03-07 are approved as AMOCs for the corresponding provisions of this AD.

(n) Related Information

(1) For more information about this AD, contact Samuel Lee, Aerospace Engineer, Propulsion Section, FAA, Los Angeles ACO Branch, 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 (o)(6) and (o)(7) of this AD.

(o) 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 May 21, 2018.

(i) Boeing Service Bulletin MD11-28-126, Revision 6, dated July 1, 2016.

(ii) Reserved.

(4) The following service information was approved for IBR on March 26, 2014 (79 FR 9392, February 19, 2014).

(i) Boeing Service Bulletin MD11-28-126, Revision 4, dated November 29, 2011.

(ii) Reserved.

(5) The following service information was approved for IBR on February 4, 2010 (74 FR 69249, December 31, 2009).

(i) Boeing Service Bulletin MD11-28-126, Revision 1, dated June 18, 2009.

(ii) Reserved.

(6) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; telephone [phone]; internet https://www.myboeingfleet.com.

(7) You may view this service information at the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.

(8) 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 Des Moines, Washington, on March 29, 2018.

Chris Spangenberg,

Acting Director, System Oversight Division, Aircraft Certification Service.