
[Federal Register Volume 88, Number 249 (Friday, December 29, 2023)]
[Proposed Rules]
[Pages 90134-90137]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-28721]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2403; Project Identifier AD-2023-00888-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 MD-11 and MD-11F airplanes 
equipped with General Electric (GE) CF6-80C2D1F high-bypass turbofan 
engines. This proposed AD was prompted by a report of a Model MD-11F 
airplane experiencing an uncommanded deployment of a thrust reverser 
in-flight at low altitude. This proposed AD would require a one-time 
detailed inspection of the engine pylon thrust reverser control system 
wire harnesses and applicable on-condition actions. The proposed AD 
would also require repetitive detailed inspections and wire integrity 
tests of the engine thrust reverser control system wire harnesses (in 
the pylon), junction box and junction box cover, left side and right 
side thrust reverser electrical harnesses, core (engine compartment) 
miscellaneous wire harness assembly, and 30 degree bulkhead wire 
harness assembly; and applicable on-condition actions. This AD also 
requires reporting. 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 February 
12, 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-2023-2403; 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

[[Page 90135]]

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 under Docket No. FAA-2023-2403.

FOR FURTHER INFORMATION CONTACT: Kevin Nguyen, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 
206-231-3555; 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-2023-2403; Project Identifier 
AD-2023-00888-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 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 Kevin 
Nguyen, Aviation Safety Engineer, FAA, 2200 South 216th St., Des 
Moines, WA 98198; telephone 206-231-3555; 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 of an MD-11F airplane equipped with 
three GE CF6-80C2D1F high-bypass turbofan engines experiencing an in-
flight deployment of the (left) engine 1 thrust reverser at 
approximately 500 feet above ground level. Both left and right 
translating cowls of the thrust reverser deployed. In the Engine 1 
pylon, damaged wiring was found, which could have caused or contributed 
to the deployment of the two transcowls.
    The FAA is issuing this AD to address uncommanded deployment of a 
thrust reverser in flight at low altitude, which could result in loss 
of control of the airplane and 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 Service Bulletin MD11-78A017, dated 
December 4, 2023. This service information specifies work package 1 
inspection procedures to do an initial detailed inspection of the 
engine 1, engine 2, and engine 3 pylon thrust reverser control system 
wire harnesses. The service information also specifies work package 2 
procedures to do repetitive detailed inspections and wire integrity 
tests at the following locations: engine 1, engine 2, and engine 3 
thrust reverser control system wire harnesses (in the pylon); junction 
box and junction box cover (only detailed inspection); left side and 
right side thrust reverser electrical harnesses; core (engine 
compartment) miscellaneous wire harness assembly; and 30 degree 
bulkhead wire harness assembly. The service information also specifies 
applicable on-condition actions (includes repairs, replacements, 
installations, post-replacement inspections and tests, and return to 
service tests). The service information also specifies that 
accomplishing the initial inspections and tests by doing Action 1 
through Action 3 in work package 2 terminates the need to do the 
inspection in accordance with Part 2 as required in work package 1. 
However, this substitution of actions does not change the compliance 
time of work package 1 as specified in Table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin MD11-78A017, dated 
December 4, 2023.
    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 identified 
as ``RC'' (required for compliance) in the Accomplishment Instructions 
of Boeing Alert Service Bulletin MD11-78A017, dated December 4, 2023, 
already described and except for any differences identified as 
exceptions in the regulatory text of this proposed AD. This proposed AD 
also requires reporting findings to Boeing. For information on the 
procedures and compliance times, see this service information at 
regulations.gov under Docket No. FAA-2023-2403.

Interim Action

    The FAA considers this proposed AD to be an interim action. The 
reports that are required by this proposed AD will enable the 
manufacturer to obtain better insight into the nature, cause, and 
extent of the unsafe condition, and eventually to develop final action 
to address the unsafe condition. If final action is later identified, 
the FAA might consider further rulemaking.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 79 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
----------------------------------------------------------------------------------------------------------------
Inspections and Tests............  Up to 78 work-hours            $0  Up to $6,630 per      Up to $523,770 per
                                    x $85 per hour = Up                inspection/test       inspection/test
                                    to $6,630 per                      cycle.                cycle.
                                    inspection/test
                                    cycle.

[[Page 90136]]

 
Reporting........................  1 work-hour x $85               0  85 per inspection/    6,715 per inspection/
                                    per hour = $85 per                 test cycle.           test cycle.
                                    inspection/test
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of the 
proposed inspections and tests. The agency has no way of determining 
the number of aircraft that might need these repairs/replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                  Action                            Labor cost           Parts cost        Cost per product
----------------------------------------------------------------------------------------------------------------
Repairs/Replacements/Tests...............  Up to 120 work-hours x $85          * $0  Up to $10,200.
                                            per hour = up to $10,200.
----------------------------------------------------------------------------------------------------------------
* The FAA has received no definitive data that would enable the FAA to provide a parts cost estimate for the on-
  condition repairs/replacements specified in this proposed AD.

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a currently valid OMB Control Number. The OMB 
Control Number for this information collection is 2120-0056. Public 
reporting for this collection of information is estimated to take 
approximately 1 hour per response, including the time for reviewing 
instructions, searching existing data sources, gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information. All responses to this collection of 
information are mandatory. Send comments regarding this burden estimate 
or any other aspect of this collection of information, including 
suggestions for reducing this burden, to Information Collection 
Clearance Officer, Federal Aviation Administration, 10101 Hillwood 
Parkway, Fort Worth, TX 76177-1524.

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-2023-2403; Project Identifier AD-
2023-00888-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by February 12, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model MD-11 and MD-11F 
airplanes, certificated in any category, equipped with General 
Electric (GE) CF6-80C2D1F high-bypass turbofan engines.

(d) Subject

    Air Transport Association (ATA) of America Code 78, Engine 
Exhaust.

(e) Unsafe Condition

    This AD was prompted by a report of a Model MD-11F airplane 
experiencing an uncommanded deployment of a thrust reverser at 
approximately 500 feet above ground level. The FAA is issuing this 
AD to address uncommanded deployment of a thrust reverser in-flight 
at low altitude, which could result in loss of flight control of the 
airplane and 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 in paragraph (h) of this AD: At the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin MD11-78A017, dated December 4, 2023, 
do all applicable actions identified as ``RC'' (required for 
compliance)

[[Page 90137]]

in, and in accordance with, the Accomplishment Instructions of 
Boeing Alert Service Bulletin MD11-78A017, dated December 4, 2023.

(h) Exceptions to Service Information Specifications

    (1) Where the Compliance Time columns of the tables in the 
``Compliance'' paragraph of Boeing Alert Service Bulletin MD11-
78A017, dated December 4, 2023, use the phrase ``the original issue 
date of this service bulletin,'' this AD requires using ``the 
effective date of this AD.''
    (2) Where step 6.c.(2)(a), ``CONDITION 14 OPTION 1 (ACTION 1)'' 
and step 6.c.(2)(b)4)d), ``CONDITION 14.4 OPTION 2 (ACTION 1)'' of 
the Accomplishment Instructions of Boeing Service Bulletin MD11-
78017, dated December 4, 2023, specify to replace the junction box, 
that replacement must be accomplished in accordance with ``PART 12: 
JUNCTION BOX REPLACEMENT'' of the Accomplishment Instructions of 
Boeing Service Bulletin MD11-78017, dated December 4, 2023.

(i) Reporting

    At the applicable time specified in paragraph (i)(1) or (2) of 
this AD, submit a report to The Boeing Company via the Boeing 
Communication System (BCS) and include the information specified in 
Appendix C of Boeing Alert Service Bulletin MD11-78A017, dated 
December 4, 2023.
    (1) If the inspection or test was done on or after the effective 
date of this AD: Submit the report within 30 days after the 
inspection or test.
    (2) If the inspection or test was done before the effective date 
of this AD: Submit the report within 30 days after the effective 
date of this AD.

(j) 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 (k) of this AD. Information may be emailed 
to [email protected].[FEDREG][VOL]*[/VOL][NO]*[/
NO][DATE]*[/DATE][PRORULES][PRORULE][PREAMB][AGENCY]*[/
AGENCY][SUBJECT]*[/SUBJECT][/PREAMB][SUPLINF][HED]*[/
HED][EXTRACT][P]*[/P]
    (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.
    (4) Except as specified by paragraph (g) of this AD: For service 
information that contains steps that are labeled as Required for 
Compliance (RC), the provisions of paragraphs (j)(4)(i) and (ii) of 
this AD apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. If a step or substep is labeled ``RC Exempt,'' then the 
RC requirement is removed from that step or substep. An AMOC is 
required for any deviations to RC steps, including substeps and 
identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(k) Related Information

    For more information about this AD, contact Kevin Nguyen, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; telephone 206-231-3555; email [email protected].

(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 Alert Service Bulletin MD11-78A017, dated December 4, 
2023.
    (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 December 22, 2023.
Caitlin Locke,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2023-28721 Filed 12-28-23; 8:45 am]
BILLING CODE 4910-13-P


