Airworthiness Directives; The Boeing Company Airplanes

[Federal Register Volume 86, Number 82 (Friday, April 30, 2021)]
[Rules and Regulations]
[Pages 22860-22862]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-09221]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0319; Project Identifier AD-2021-00443-T; 
Amendment 39-21521; AD 2021-09-08]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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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 manufacturing design changes to certain metallic support 
panel assemblies installed in the flight deck, which resulted in 
insufficient electrical bonding of the panels and consequent 
insufficient electrical grounding of installed equipment. This AD 
requires modification of the electrical bonding of these assemblies to 
provide sufficient electrical grounding for equipment installed in the 
flight deck. The FAA is issuing this AD to address the unsafe condition 
on these products.

DATES: This AD is effective April 30, 2021.
    The FAA must receive comments on this AD by June 14, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
    <bullet> Fax: 202-493-2251.
    <bullet> Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
    <bullet> Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0319; 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 street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: 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: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The 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 first officer. 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

[[Page 22861]]

been 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.
    Degradation 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.
    All 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.

FAA's Determination

    The 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.

AD Requirements

    This 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.
    The 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.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.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.
    An 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).
    In 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.

Comments Invited

    The 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 of your 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.
    Except 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.

Confidential Business Information

    CBI 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: [email protected]. Any 
commentary that the FAA receives that is not specifically designated as 
CBI will be placed in the public docket for this rulemaking.

Regulatory Flexibility Act

    The 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.

Costs of Compliance

    The FAA estimates that this AD affects 71 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Modify multiple flight deck panels (68  24 work-hours x $85 per             $200          $2,240        $152,320
 airplanes).                             hour = $2,040.
Modify one flight deck panel (3         9 work-hours x $85 per               100             865           2,595
 airplanes).                             hour = $765.
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[[Page 22862]]

    The 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.

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, and
    (2) Will not affect intrastate aviation in Alaska.

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

0
1. The authority citation for part 39 continues to read as follows:

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


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2021-09-08 The Boeing Company: Amendment 39-21521; Docket No. FAA-
2021-0319; Project Identifier AD-2021-00443-T.

(a) Effective Date

    This airworthiness directive (AD) is effective April 30, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-8 and 737-9 
airplanes, certificated in any category, line numbers 7399 through 
8082 inclusive, with an original airworthiness certificate or 
original export certificate of airworthiness issued on or before 
April 9, 2021.

(d) Subject

    Air Transport Association (ATA) of America Code 24, Electrical 
power system.

(e) Unsafe Condition

    This AD was prompted by manufacturing design changes to certain 
metallic support panel assemblies installed in the flight deck. The 
design changes resulted in insufficient bonding of the panel 
assemblies and consequent insufficient electrical grounding of 
installed equipment. Degradation of bonds essential for the 
electrical grounding of equipment could affect the operation of 
certain systems, including engine ice protection. The FAA is issuing 
this AD to prevent loss of critical functions and/or multiple 
simultaneous flight deck effects, which may prevent continued safe 
flight and landing.

(f) Compliance

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

(g) Modification

    Before further flight, modify the electrical bonding of the 
support panel assemblies installed in the flight deck to provide 
sufficient electrical grounding for equipment installed in the 
flight deck, as specified in paragraphs (g)(1) and (2) of this AD, 
as applicable, in accordance with a method approved by the Manager, 
Seattle ACO Branch, FAA.
    (1) Modify the electrical bonding of the P6 panel assembly, 
including the mounting tray for the standby power control unit 
(SPCU), located behind the first officer.
    (2) Modify the electrical bonding of the main instrument panel 
(MIP) assembly located in front of and between the captain and first 
officer.

(h) Special Flight Permit

    Special flight permits may be issued in accordance with 14 CFR 
21.197 and 21.199 to operate the airplane to a location where the 
airplane can be modified, provided the provisions specified in 
paragraphs (h)(1), (2), and (3) of this AD are met.
    (1) The MAX display system (the inboard and outboard captain's 
and first officer's displays) is operative.
    (2) The very high frequency (VHF) communication system (all VHF 
radios) is operative.
    (3) The airplane is modified to improve the grounding path for 
the SPCU, in accordance with a method approved by the Manager, 
Seattle ACO Branch, FAA.

(i) 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 responsible Flight Standards Office, 
as appropriate. If sending information directly to the manager of 
the certification office, send it to the attention of the person 
identified in Related Information. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards 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.

(j) Related Information

    For more information about this AD, contact 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: [email protected].

(k) Material Incorporated by Reference

    None.

    Issued on April 27, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-09221 Filed 4-28-21; 2:00 pm]
BILLING CODE 4910-13-P

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