[Federal Register Volume 89, Number 31 (Wednesday, February 14, 2024)]
[Proposed Rules]
[Pages 11231-11233]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-02993]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0229; Project Identifier AD-2023-00485-T]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain The Boeing Company Model 737-8 and Model 737-9 airplanes. 
This proposed AD was prompted by a Boeing review of the standby power 
system control unit (SPCU) design where a single point of failure 
exists internal to the SPCU. This proposed AD would require the 
installation of four diodes and changing wire bundles in the P5 panel, 
as well as performing installation and power tests and applicable on-
condition actions. The FAA is proposing this AD to address the unsafe 
condition on these products.

DATES: The FAA must receive comments on this proposed AD by April 1, 
2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow 
the instructions for submitting comments.
     Fax: 202-493-2251.
     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.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0229; 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 NPRM, any comments received, and other 
information. The street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For service information identified in this NPRM, 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; website 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 at 
regulations.gov by searching for and locating Docket No. FAA-2024-0229.

FOR FURTHER INFORMATION CONTACT: Hoang Yen Dang, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 
206-231-3610; email [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2024-0229; Project Identifier 
AD-2023-00485-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, 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 proposal 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 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this NPRM.

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 NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or

[[Page 11232]]

responsive to this NPRM, 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 NPRM. Submissions containing CBI should be 
sent to Hoang Yen Dang, Aviation Safety Engineer, FAA, 2200 South 216th 
St., Des Moines, WA 98198; telephone 206-231-3610; 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.

Background

    The FAA has received a report indicating that a Boeing review of 
the SPCU design revealed that a potential single point of failure 
exists internal to the SPCU. This condition, if not addressed, could 
result in a non-latent single point of failure, which can result in a 
non-latent loss of the entire battery buss and consequent un-
annunciated loss of control and indication of both engine anti-ice 
(EAI) systems.
    The unsafe condition, if not addressed, could result in loss of 
thrust on both engines due to damage from operation in icing conditions 
without EAI and can result in loss of continued safe flight and 
landing.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 737-30A1083 RB, 
dated November 18, 2022. This service information specifies procedures 
for the installation of four diodes and changing wire bundles in the P5 
panel, as well as performing an anti-ice diode installation test and an 
engine anti-ice and wing anti-ice power test and applicable on-
condition actions. On-condition actions include doing applicable 
corrective actions until the tests are passed.
    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 ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information already described and except for any 
differences identified as exceptions in the regulatory text of this 
proposed AD. Interim Action.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 205 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                   Labor cost          Parts cost       Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Installation, Wiring bundle       Up to 18 work-      Up to $3,760......  Up to $5,290......  Up to $1,084,450.
 changes, and tests.               hours x $85 per
                                   hour = Up to
                                   $1,530.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data on which to base the cost 
estimates for the on-condition actions specified in this proposed AD.
    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this proposed 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

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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:

The Boeing Company: Docket No. FAA-2024-0229; Project Identifier AD-
2023-00485-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by April 1, 2024.

 (b) Affected ADs

    None.

 (c) Applicability

    This AD applies to The Boeing Company Model 737-8 and 737-9 
airplanes, certificated in any category, having a line number 
identified in paragraph 1.A.,

[[Page 11233]]

``Effectivity,'' of Boeing Alert Requirements Bulletin 737-30A1083 
RB, dated November 18, 2022.

 (d) Subject

    Air Transport Association (ATA) of America Code 30, Ice/Rain 
Protection System.

 (e) Unsafe Condition

    This AD was prompted by a Boeing review of the standby power 
system control unit (SPCU) design that determined a potential single 
point of failure exists in the SPCU. The FAA is issuing this AD to 
address a potential single point of failure in the SPCU, which can 
result in a non-latent loss of the entire battery buss and 
consequent un-annunciated loss of control and indication of both 
engine anti-ice (EAI) systems. The unsafe condition, if not 
addressed, could result in loss of thrust on both engines due to 
damage from operation in icing conditions without EAI and can result 
in loss of continued safe flight and landing.

 (f) Compliance

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

 (g) Required Actions

    Except as specified by paragraph (h) of this AD: At the 
applicable times specified in the ``Compliance'' paragraph of Boeing 
Alert Requirements Bulletin 737-30A1083 RB, dated November 18, 2022, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
737-30A1083 RB, dated November 18, 2022.

    Note 1 to paragraph (g): Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
737-30A1083, dated November 18, 2022, which is referred to in Boeing 
Alert Requirements Bulletin 737-30A1083 RB, dated November 18, 2022.

 (h) Exceptions to Service Information Specifications

    (1) Where the Compliance Time columns of the table in the 
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 737-
30A1083 RB, dated November 18, 2022, uses the phrase ``the original 
issue date of Requirements Bulletin 737-30A1083 RB,'' this AD 
requires using the effective date of this AD.
    (2) Where ``ACTION 3'' in the Action column of the table in the 
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 737-
30A1083 RB, dated November 18, 2022, specifies to do applicable 
corrective actions and repeat the test until the test passes if any 
test fails, for this AD, the compliance time for those actions is 
before further flight after accomplishing the test.

 (i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, AIR-520, Continued Operational Safety 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 AIR-520, Continued 
Operational Safety Branch, send it to the attention of the person 
identified in paragraph (j)(1) of this AD. 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, AIR-
520, Continued Operational Safety 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

    (1) For more information about this AD, contact Hoang Yen Dang, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; telephone 206-231-3610; email [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (k)(3) and (4) of this AD.

 (k) 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 Alert Requirements Bulletin 737-30A1083 RB, dated 
November 18, 2022.
    (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; website 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 material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on February 8, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-02993 Filed 2-13-24; 8:45 am]
BILLING CODE 4910-13-P