Background \n\n\n\tThe FAA has received a report of an electrical bonding and grounding issue that was discovered during testing of a newly manufactured Boeing Model 737-8 airplane. During standard production testing by Boeing, electrical power systems did not perform as expected. Investigation identified insufficient bonding of certain metallic support panel assemblies installed in two areas of the flight deck, which affects the electrical grounding of installed equipment. The reported event occurred prior to delivery of that airplane. Investigation identified design changes to the flight deck support panel assemblies, which affected the dedicated bonding and grounding paths that existed prior to the changes. The affected areas are the P6 panel assembly, including the mounting tray for the standby power control unit (SPCU), located behind the first officer, and the main instrument panel (MIP) assembly located in front of and between the captain and firstofficer. The issue affects certain Boeing Model 737-8 and 737-9 airplanes manufactured after the design changes were implemented. All affected in-service airplanes passed all testing prior to delivery, and there have \n\n((Page 22861)) \n\nbeen no reported in-service failures due to this condition. However, without dedicated grounding paths implemented by design, there is a potential for degradation or loss of the existing uncontrolled ground paths on those airplanes over time. \n\tDegradation of bonds essential for the electrical grounding of equipment, if not addressed, could affect the operation of certain systems, including engine ice protection, and result in loss of critical functions and/or multiple simultaneous flight deck effects, which may prevent continued safe flight and landing. The FAA is issuing this AD to address the unsafe condition on these products. \n\tAll affected airplanes, both in the U.S. and worldwide, have been removed from service, pending development and implementation of approved corrective action that will address the unsafe condition. \n\nFAA's Determination \n\n\n\tThe FAA is issuing this AD because the agency has determined that the unsafe condition described previously is likely to exist or develop in other products of the same type design. \n\nAD Requirements \n\n\n\tThis AD requires modifying the electrical bonding of certain support panel assemblies installed in the flight deck to provide sufficient electrical grounding for equipment installed in the flight deck. \n\tThe manufacturer is currently developing service information for a modification that will address the unsafe condition identified in this AD. Once this service information is developed, approved, and available, the FAA intends to approve that service information as a method of compliance for the requirements of this AD. \n\nJustification for Immediate Adoption and Determination of the Effective Date \n\n\n\tSection 553(b)(3)(B) of the Administrative Procedure Act (APA) (5U.S.C. 551 et seq.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for ''good cause,'' finds that those procedures are ''impracticable, unnecessary, or contrary to the public interest.'' Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause. \n\tAn unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. On April 7, 2021, the FAA was advised by the manufacturer that its design changes to the referenced panel assemblies had created an urgent safety issue. On April 9, 2021, the manufacturer recommended to operators of affected airplanes that such airplanes be removed from service. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because degradation of bonds essential for the electrical grounding of equipment could affect the operation of certain systems, including engine ice protection, and result in loss of critical functions and/or multiple simultaneous flight deck effects, which may prevent continued safe flight and landing. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b)(3)(B). \n\tIn addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment. \n\nComments Invited \n\n\n\tThe FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under ADDRESSES. Include Docket No. FAA-2021-0319 and Project Identifier AD- 2021-00443-T at the beginning ofyour comments. The most helpful comments reference a specific portion of the final rule, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments. \n\tExcept for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule. \n\nConfidential Business Information \n\n\n\tCBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this AD contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this AD, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ''PROPIN.'' The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this AD. Submissions containing CBI should be sent to Julio Alvarez, Aerospace Engineer, Systems and Equipment Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3500; email: 9-FAA-SACO-AD-Inquiry@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. \n\nRegulatory Flexibility Act \n\n\n\tThe requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 71 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Modify multiple flight deck panels (68 24 work-hours x $85 per $200 $2,240 $152,320 \n\tairplanes). hour = $2,040. Modify one flight deck panel (3 9 work-hours x $85 per 100 865 2,595 \n\tairplanes).hour = $765. ---------------------------------------------------------------------------------------------------------------- \n\n\n\n((Page 22862)) \n\n\n\tThe FAA has included all estimated costs in the cost estimate. Some or all of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. \n\nAuthority for This Rulemaking \n\n\n\tTitle 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. \n\tThe 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. \n\nRegulatory Findings \n\n\n\tThis 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. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, and \n\t(2) Will not affect intrastate aviation in Alaska. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.