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Airworthiness Directives; The Boeing Company Airplanes

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Start Preamble

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-8 and 737-9 airplanes. This AD was prompted by a report that certain exterior fairing panels on the top of the engine nacelle and strut (the thumbnail fairing and mid strut fairing panels) may not have the quality of electrical bonding necessary to ensure adequate shielding of the underlying wiring from the electromagnetic effects of high intensity radiated fields (HIRF), which could potentially lead to a dual-engine power loss event and/or display of hazardously misleading primary propulsion parameters. This AD requires a detailed inspection of the thumbnail fairing panels and mid strut fairing panels for excessive rework of the metallic (aluminum foil) inner surface layer, replacement of any excessively reworked panels, and modification of the thumbnail fairing assembly to ensure adequate bonding. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective July 30, 2020.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of July 30, 2020.

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 90740-5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety 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 https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0091.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0091; 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, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Christopher Baker, Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3552; email: christopher.r.baker@faa.gov.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain The Boeing Company Model 737-8 and 737-9 airplanes. The NPRM published in the Federal Register on February 26, 2020 (85 FR 11000). The NPRM was prompted by a report that certain exterior fairing panels on the top of the engine nacelle and strut (the thumbnail fairing and mid strut fairing panels) may not have the quality of electrical bonding necessary to ensure adequate shielding of the underlying wiring from the electromagnetic effects of HIRF, which could potentially lead to a dual-engine power loss event and/or display of hazardously misleading primary propulsion parameters. The NPRM proposed to require a detailed inspection of the thumbnail fairing panels and mid strut fairing panels for excessive rework of the metallic (aluminum foil) inner surface layer, replacement of any excessively reworked panels, and modification of the thumbnail fairing assembly to ensure adequate bonding.

The FAA is issuing this AD to address this condition, which could result in a forced off-airport landing or excessive flightcrew workload.

Comments

The FAA gave the public the opportunity to participate in developing this final rule. The FAA received comments from several organizations and individuals. The following discussion presents the comments Start Printed Page 38056received on the NPRM and the FAA's response to each comment.

Support for the NPRM

The Air Line Pilots Association, International (ALPA) and three individuals expressed support for the NPRM.

Request To Exclude Certain Airplanes From the AD's Applicability

United Airlines (UAL) requested that the proposed AD be revised to exclude airplanes that have not been delivered. UAL noted that the proposed AD would apply to all Model 737-8 and 737-9 airplanes included in line numbers 5602 through 7901, which is beyond the effectivity of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019. UAL reasoned that for airplanes that have not been delivered, Boeing would incorporate the intent of the service bulletin at the factory, which would provide an equivalent level of safety. UAL suggested that if those airplanes are not excluded from the proposed AD's applicability, the FAA should provide credit to prevent the need for future alternative method of compliance (AMOC) requests.

The FAA agrees with the commenter, for the reasons the commenter provided. The FAA has revised paragraph (c) of this AD to limit the applicability to those airplanes identified in Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019.

Request To Refer To Correct Part Numbers

American Airlines (AAL) and UAL requested that the proposed AD be revised to correct the part number for the thumbnail fairing. UAL noted that Figure 2 and Figure 8 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, specify certain thumbnail fairings, but those figures specify the incorrect part numbers. The commenters noted that Boeing issued Information Notice 737-54-1056 IN 01, dated January 29, 2020, to correct the part numbers. This Information Notice is in the docket for this rulemaking, attached to the comment of Hainan Airlines Aviation Technic (Hainan). UAL added that, although the Information Notice specifies the correct “IS” part numbers, it specifies the wrong “WAS” part numbers, and noted that Boeing plans to address this in a future Information Notice or service bulletin revision. UAL asked that the final rule include an exception to allow inspection and installation of thumbnail fairings having the correct part number.

The FAA agrees with the commenters' requests. The FAA has added paragraph (h) of this AD to include exceptions to the service information; this includes paragraph (h)(1) of this AD, which identifies the correct part numbers to be used when accomplishing the service instructions. Operators must use part number 313A6110-5, 313A6110-7, or 313A6110-9 in lieu of part number 311A6111-5, 311A6111-7, or 311A6111-9 when inspecting or installing affected thumbnail fairings. The FAA has also redesignated subsequent paragraphs accordingly.

Request To Clarify Rivet Hole Size

AAL suggested to the FAA that the proposed AD be revised to clarify the rivet hole size called out for installing a nutplate. AAL stated that note (d) to Figure 4 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, specifies to drill a hole with a diameter of “0.192—0.196.” AAL stated that Boeing confirmed the rivet hole size will be corrected with a revised service bulletin.

The FAA agrees that the rivet hole size specified in note (d) to Figure 4 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, is incorrect. SB 737-54-1056 Revision 1, corrects this hole size diameter with the following language: “(d) Drill through Thumbnail Land Assembly with a hole Diameter of 0.097—0.101.” The FAA has added paragraph (h)(2) to this AD to clarify the correct rivet hole size to use when installing a nutplate.

Request To Clarify the Inspection and Replacement Criteria for Critical and Non-Critical Bonding Zones

Hainan requested that the proposed AD be revised to provide clarification regarding the inspection and replacement criteria for critical and non-critical bonding zones (which are specified in Step 4 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019). Hainan noted that Boeing Information Notice 737-54-1056 IN 01, dated January 29, 2020, provides clarity regarding the inspection and the conditions that require replacement of the panels.

The FAA agrees with the commenter's request. The FAA has added paragraph (h)(3) of this AD to clarify the inspection and replacement criteria for critical bonding zones. The FAA has also added paragraph (h)(4) of this AD to clarify the inspection and replacement criteria for non-critical bonding zones.

Request To Revise Certain Background Information

Boeing requested that paragraph (e) of the proposed AD as well as the SUMMARY and the Discussion section in SUPPLEMENTARY INFORMATION of the NPRM be revised to be consistent with the potential aircraft system impacts Boeing communicated in reporting this issue to the FAA prior to issuance of the NPRM, and to remove any references to an unsafe condition resulting from lightning strikes. Boeing stated that the descriptions of the potential unsafe conditions in the proposed AD are inconsistent with its subject matter expert's evaluation of the safety issue. Boeing added that there is not a safety concern in the event of a lightning strike, because all of the electrical and electronic systems with wiring in the affected area retain sufficient margin between their design and qualification levels and the lightning-induced transient levels, even with the loss of electrical bonding of the foil-lined panels in the engine strut. Boeing further noted that the proposed AD does not mention the potential for displays of misleading primary propulsion parameters on the flight deck displays. Boeing stated that the proposed AD inaccurately describes a scenario where HIRF or lightning induced on one engine's wiring could cross-couple to the opposite engine's wiring via the common avionics system's connections. Boeing provided suggestions for revised wording.

The FAA agrees with the commenter's request for the reasons provided. Based on further analysis done after issuance of the NPRM, the FAA has determined that lightning strikes are not a safety concern for the unsafe condition identified in this AD. The FAA has revised the SUMMARY and the Discussion section in SUPPLEMENTARY INFORMATION of this final rule as well as paragraph (e) of this AD to incorporate the changes requested by Boeing.

Request To Revise Special Flight Permit Conditions

Boeing requested that the special flight permit language in paragraph (i) of the proposed AD be revised to provide guidance on the HIRF spectrum of concern to operators. Boeing noted that the potential for aircraft systems' exposure to HIRF levels higher than their original qualification levels is limited to the frequency range between 1 MHz and 100 MHz. Boeing stated that operators do not need to consider potential HIRF sources outside this frequency spectrum when assessing routes for special flight permit requests. Start Printed Page 38057Boeing added that providing clarification on the frequency range of concern would reduce the burden on both operators and the FAA in submitting and reviewing special flight permit requests.

The FAA agrees with the request because the agency has determined that only the HIRF frequency range between 1 MHz and 100 MHz is of concern. The FAA has revised paragraph (i) of this AD to clarify the HIRF frequency range that must be identified when submitting a request for a special flight permit.

Request To Change Compliance Time to Before Revenue Flight

Boeing requested that the compliance time in the proposed AD be changed from “before further flight” to “before revenue flight.” Boeing noted that the compliance time in Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, is six months. Boeing added that it is revising the service bulletin and plans to change the compliance time to “prior to revenue flight” in the revised service bulletin. Boeing noted that “prior to revenue flight” aligns with the Boeing safety review board recommendation.

The FAA disagrees with the commenter's request. Without the safety features installed during the modification required by this AD, airplanes are exposed to potentially unsafe electromagnetic effects. The FAA has included provisions in paragraph (i) of this AD (paragraph (h) of the proposed AD) for operators who may need to relocate an airplane prior to accomplishing the actions required by this AD. The FAA has not changed this AD regarding this issue.

Request To Revise Compliance Time To Include Options

Hainan requested that the compliance time for the proposed AD be revised to “within six months after the effective date of this AD or before further flight, whichever occurs first.” Hainan noted that Boeing recommended a compliance time of within six months after the original issue date of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019. Hainan suggested that, due to the unknown return-to-service dates for the affected airplanes, a revised compliance time would allow airlines to plan for the actions required by this AD. Hainan pointed out that another recent AD on these same airplane models has a compliance time of 24 months.

The FAA disagrees with the commenter's request. Without the safety features installed during the modification required by this AD, airplanes are exposed to potentially unsafe electromagnetic effects. The FAA notes that the compliance time is designed to ensure the actions required by this AD are done before further flight (i.e., before the affected airplanes are returned to service), and operators may do these actions at any time before further flight. The FAA has not changed this AD regarding this issue.

Request To Include a Grace Period

Hainan requested that the proposed AD be revised to provide a grace period for the required modification. Hainan stated that Boeing can only provide new panels based on the results of required inspections. Hainan suggested that due to the international transportation impacts caused by the 2019 Novel Coronavirus, new panels may not be available to operators in a timely manner.

As a result of Hainan's comment, the FAA confirmed in June 2020 that a sufficient number of required parts will be available from the manufacturer to modify the worldwide fleet within the compliance time of the NPRM, which is adopted as proposed. However, under the provisions of paragraph (j) of this AD, the FAA will consider requests for approval of an extension of the compliance time if sufficient data are submitted to substantiate that the new compliance time would provide an acceptable level of safety. The FAA has not changed this AD regarding this issue.

Request To Clarify Certain Requirements

Hainan requested that paragraph (g) of the proposed AD be revised to specify “replacement and modification” rather than “modification.” Hainan noted that the actions in the proposed AD include both modification and replacement.

Paragraph (g) of the proposed AD specified a detailed inspection and the modification as applicable. Replacement is one part of the modification, and is required only if excessive rework is found during that inspection. Thus, the FAA has determined that specifying “replacement and modification” in paragraph (g) of this AD is not necessary, and the agency has not changed this AD regarding this issue.

Request To Revise Wording Regarding Required Steps

Hainan requested that the wording in paragraph (g) of the proposed AD be revised to specify “Steps 4., 6. or 7. through 9., . . .” instead of “Steps 4., 6. through 9., inclusive . . . .” Hainan noted that Steps 6. and 7. of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, are two different options for one action.

The FAA acknowledges that Steps 6. and 7. of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, are two options for the same action. However, the FAA notes that this is clearly stated in Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, which labels Step 6. as “ACTION 2 (OPTION 1)” and Step 7. as “ACTION 2 (OPTION 2).” Operators are required to do only one of these options to show compliance with this AD. The FAA has not changed this AD regarding this issue.

Request To Provide Steps for Deactivating Certain Slats

AAL suggested to the FAA that the proposed AD be revised to include steps to deactivate the slats. AAL noted that Boeing recommended deactivating the slats and thrust reversers using the Aircraft Maintenance Manual (AMM) as an accepted procedure and stated such instructions would be included in a revision of the service information.

The FAA agrees that deactivating the slats prior to accomplishing the actions specified in the service bulletin would help to protect any maintenance personnel working on that area, and that the AMM provides acceptable procedures for deactivating the slats. However, the FAA does not agree with making slat deactivation a requirement of this AD, since this procedure is not needed to address the unsafe condition. The FAA has not changed this AD regarding this issue.

Request To Account for Possible Service Information Revision in the Final Rule

AAL suggested to the FAA that the proposed AD be updated to account for a revision of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, if one exists. AAL noted that Boeing stated that such a revision is in process and AAL asked if the FAA is aware of such a revision.

The FAA acknowledges that Boeing has informed the agency of its intent to issue revised service information. However, that revision has not yet been published by Boeing. As stated earlier, the FAA has added several exceptions to this AD to correct errors in Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019. With these exceptions, operators will be able to comply with this AD using Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019.Start Printed Page 38058

Explanation of Additional Change to This AD

The FAA clarifies that where the AD specifies to perform certain “Steps” of the Boeing service bulletin, such steps refer to the numbered actions specified within the Procedures section of the Accomplishment Instructions. The FAA has revised paragraph (g) of this AD to change the required procedures by not including steps 9 and 12 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019. The FAA has determined that these steps, while expected to be accomplished, are not required to address the unsafe condition identified in this AD and this change makes this AD consistent with revision 1 of the Boeing service information.

Conclusion

The FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the changes described previously and minor editorial changes. The FAA has 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 more burden upon the public than was already proposed in the NPRM.

The FAA also determined that these changes will not increase the economic burden on any operator or increase the scope of this final rule.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019. This service information describes procedures for a detailed inspection of the thumbnail fairing panels and mid strut fairing panels for excessive rework of the metallic (aluminum foil) inner surface layer (resulting in foil cuts), replacement of any excessively reworked panels, and modification of the thumbnail fairing assembly to ensure adequate bonding. Modification actions include doing a form-in-place gasket of the thumbnail land assemblies; preparing the mating surfaces between the thumbnail fairing panel and the left and right thumbnail land assemblies; and doing a bond check of the thumbnail fairing panel and the thumbnail land assemblies on the left and right side of the thumbnail fairing panel on both engines. 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

The FAA estimates that this AD affects 128 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs

ActionLabor costParts costCost per productCost on U.S. operators
Inspection5 work-hours × $85 per hour = $425$0$425$54,400

The FAA estimates the following costs to do any necessary modifications that would be required based on the results of the required inspection. The FAA has no way of determining the number of aircraft that might need these modifications:

On-Condition Costs

ActionLabor costParts costCost per product
ModificationUp to 7 work-hours × $85 per hour = Up to $595(*)Up to $595.*
* The FAA has received no definitive data that would enable the agency to provide parts cost estimates for the on-condition actions specified in this AD.

According to the manufacturer, all of the costs of this AD will be covered under warranty, thereby reducing the cost impact on affected operators. The FAA does not control warranty coverage for affected operators. As a result, the FAA has included all known costs in the cost estimate.

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.

The FAA is 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) Will not affect intrastate aviation in Alaska, and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Start List of Subjects

List of Subjects in 14 CFR Part 39

  • Air transportation
  • Aircraft
  • Aviation safety
  • Incorporation by reference
  • Safety
End List of Subjects Start Printed Page 38059

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

End Part Start Amendment Part

1. The authority citation for part 39 continues to read as follows:

End Amendment Part Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]
Start Amendment Part

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

End Amendment Part

2020-11-12 The Boeing Company: Amendment 39-19916; Docket No. FAA-2020-0091; Product Identifier 2020-NM-012-AD.

(a) Effective Date

This AD is effective July 30, 2020.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 737-8 and 737-9 airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019.

(d) Subject

Air Transport Association (ATA) of America Code 54, Nacelles/pylons.

(e) Unsafe Condition

This AD was prompted by a report that certain exterior fairing panels on the top of the engine nacelle and strut (the thumbnail fairing and mid strut fairing panels) may not have the quality of electrical bonding necessary to ensure adequate shielding of the underlying wiring from the electromagnetic effects of high intensity radiated fields (HIRF), which could potentially lead to a dual-engine power loss event and/or display of hazardously misleading primary propulsion parameters. The FAA is issuing this AD to address this condition, which could result in a forced off-airport landing or excessive flightcrew workload.

(f) Compliance

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

(g) Detailed Inspection and Modification

Before further flight, do a detailed inspection of the thumbnail fairing panels and mid strut fairing panels for excessive rework of the metallic (aluminum foil) inner surface layer, and, before further flight, do the modification as applicable in accordance with Steps 4., 6. through 8. inclusive, and 11. of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019.

(h) Exceptions to Service Information Specifications

(1) Where Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, specifies thumbnail fairings having part number “311A6111-5 or 311A6111-7 or 311A6111-9,” for this AD use part number “313A6110-5 or 313A6110-7 or 313A6110-9.”

(2) Where note (d) to Figure 4 of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, specifies to drill a hole with a diameter of “0.192-0.196,” for this AD the hole diameter must be “0.097-0.101.”

(3) For inspections of critical bonding areas, as specified in Step 4.a. of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, any panel with cumulative foil cut lengths greater than 4.0 inches within any 12.0 inches in length must be replaced; any panel with a foil cut gap greater than 0.25 inch also must be replaced.

(4) For inspections of non-critical bonding areas, as specified in Step 4.b. of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-54-1056, dated December 11, 2019, any panel with cumulative foil cut lengths greater than 12.0 inches within a 12.0-inch by 12.0-inch area must be replaced; any panel with a foil cut gap greater than 0.25 inch also must be replaced.

(i) Special Flight Permit

Special flight permits, as described in 14 CFR 21.197 and 21.199, may be issued to operate the airplane to a location where the requirements of this AD can be accomplished, but concurrence by the Manager, Seattle ACO Branch, FAA, is required before issuance of the special flight permit. Requests for a special flight permit must be submitted to the FAA with a description of the electromagnetic field radiation sources (type, location, frequency, and power level) along the planned route. Only electromagnetic field radiation sources operating in the frequency spectrum between 1 MHz and 100 MHz need to be identified when submitting a special flight permit request (common examples of such sources include, but are not limited to, short wave radio towers, FM radio towers, and some TV broadcast transmitters). Send requests for a special flight permit to the person identified in paragraph (k) of this AD.

(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle 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 (k) of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.

(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 Company Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO Branch, FAA, 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.

(k) Related Information

For more information about this AD, contact Christopher Baker, Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3552; email: christopher.r.baker@faa.gov.

(l) 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 737-54-1056, dated December 11, 2019.

(ii) [Reserved]

(3) 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 90740-5600; telephone 562 797 1717; internet https://www.myboeingfleet.com.

(4) You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.

(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, email fedreg.legal@nara.gov, or go to: https://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Start Signature

Issued on June 11, 2020.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.

End Signature End Supplemental Information

[FR Doc. 2020-13481 Filed 6-24-20; 8:45 am]

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