[Federal Register Volume 86, Number 150 (Monday, August 9, 2021)]
[Rules and Regulations]
[Pages 43404-43406]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-16972]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0614; Project Identifier AD-2021-00831-T; 
Amendment 39-21677; AD 2021-16-15]
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 all 
The Boeing Company Model 737-8, 737-9, and 737-8200 (737 MAX) 
airplanes; and certain Model 737-800 and 737-900ER series airplanes. 
This AD was prompted by the determination that the aft cargo 
compartment fire suppression capability is reduced if the airplane is 
dispatched or released with failed electronic flow control of air 
conditioning packs, as is currently allowed by these airplane models' 
master minimum equipment lists (MMELs). This AD prohibits the carriage 
of cargo in the aft cargo compartment when the airplane is dispatched 
or released with failed electronic flow control of air conditioning 
packs. The FAA is issuing this AD to address the unsafe condition on 
these products.

DATES: This AD is effective August 9, 2021.
    The FAA must receive comments on this AD by September 23, 2021.

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 https://www.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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0614; 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: Sam Nalbandian, Aerospace Engineer, 
Cabin Safety and Environmental Systems Section, FAA, Seattle ACO 
Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-
231-3993; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA was notified by Boeing in March 2021 of a potential concern 
that the aft cargo compartment fire suppression capability is reduced 
on affected airplanes if the airplane is dispatched or released with 
failed electronic flow control of air conditioning packs, as is 
currently allowed by the existing FAA-approved MMEL of the affected 
airplane models. This MMEL allowance can result in the inability to 
contain a fire in the aft cargo compartment due to increased air 
leakage that degrades the fire suppression performance. A failed 
electronic flow control of air conditioning packs would significantly 
increase the pack airflow and cargo compartment air leakage. In April 
2021, Boeing advised the FAA that such increased leakage could result 
in insufficient concentration of Halon fire suppressant in the aft 
cargo compartment, which can result in the inability to contain a fire 
for the time necessary to divert to a suitable airport.
    The FAA is issuing this AD to address failed electronic flow 
control of air conditioning packs, which can result in an uncontained 
aft cargo compartment fire due to insufficient cargo fire suppression 
capability. The FAA is issuing this AD to address the unsafe condition 
on these products.

FAA's Determination

    The FAA is issuing this AD because the agency has determined the 
unsafe condition described previously is likely to exist or develop in 
other products of the same type design.

AD Requirements

    This AD prohibits dispatch or release of an airplane with cargo in 
the aft cargo compartment with failed electronic flow control of air 
conditioning packs. The AD specifically allows non-combustible and/or 
non-flammable empty cargo handling equipment, ballast, and/or fly-away 
kits in the aft cargo compartment.

MMEL Revisions

    This AD refers to items in ATA System No. 21, Air Conditioning, of 
Boeing 737 (B-737-100/200/300/400/500/600/700/800/900/900ER) MMEL, 
Revision 61, dated July 8, 2020; and Boeing 737 MAX (B-737-8/-8200/-9) 
MMEL, Revision 3, dated April 12, 2021; \1\ those items may also be 
included in an operator's FAA-approved minimum equipment list (MEL). 
This AD prohibits dispatch or release of the airplane under conditions 
currently allowed by those items in the MMEL. The FAA plans to revise 
the MMELs to modify those items; operators would then be required to 
also revise their applicable existing FAA-approved MEL accordingly.
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    \1\ The MMEL items can be found in the applicable FAA-approved 
MMEL, which can be found on the Flight Standards Information 
Management System (FSIMS) website, https://fsims.faa.gov/PICResults.aspx?mode=Publication&doctype=MMELByModel.
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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

[[Page 43405]]

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. The FAA has found that the risk to the flying public 
justifies forgoing notice and comment prior to adoption of this rule 
because failed electronic flow control of air conditioning packs can 
result in an uncontained aft cargo compartment fire due to insufficient 
cargo fire suppression capability. 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-2021-0614 and Project Identifier AD-
2021-00831-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 Sam 
Nalbandian, Aerospace Engineer, Cabin Safety and Environmental Systems 
Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 
98198; phone and fax: 206-231-3993; 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 663 airplanes of U.S. 
registry.
    The FAA has determined that revising the operator's existing FAA-
approved MEL, if accomplished in association with compliance for the 
requirements of this AD, would take an average of 90 work-hours per 
operator, although the agency recognizes that this number may vary from 
operator to operator. Since operators typically incorporate MEL changes 
for their affected fleets, the FAA has determined that a per-operator 
estimate is more accurate than a per-airplane estimate. Therefore, the 
FAA estimates the average total cost per operator to be $7,650 (90 
work-hours x $85 per work-hour).

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:

2021-16-15 The Boeing Company: Amendment 39-21677; Docket No. FAA-
2021-0614; Project Identifier AD-2021-00831-T.

(a) Effective Date

    This airworthiness directive (AD) is effective August 9, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company airplanes, certificated in 
any category, as identified in paragraphs (c)(1) through (3) of this 
AD.
    (1) All Model 737-8, 737-9, and 737-8200 airplanes.
    (2) Model 737-800 series airplanes, line numbers 5684 and 5759 
and subsequent.
    (3) Model 737-900ER series airplanes, line numbers 5768 and 
subsequent.

[[Page 43406]]

(d) Subject

    Air Transport Association (ATA) of America Code 21, Air 
conditioning.

(e) Unsafe Condition

    This AD was prompted by the determination that the aft cargo 
fire suppression capability is reduced if the airplane is dispatched 
or released with failed electronic flow control of air conditioning 
packs. The FAA is issuing this AD to address this condition, which 
can result in an uncontained aft cargo compartment fire due to 
insufficient cargo fire suppression capability.

(f) Compliance

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

(g) Conditions for Prohibited Operation

    Beginning August 19, 2021, no person may dispatch or release an 
airplane with cargo in the aft cargo compartment with failed 
electronic flow control of air conditioning packs, unless the aft 
cargo compartment remains empty, or is verified by the operator to 
contain only non-combustible and/or non-flammable empty cargo 
handling equipment, ballast, and/or fly-away kits.
    Note 1 to paragraph (g): The operator's existing FAA-approved 
minimum equipment list (MEL) defines which items are approved for 
inclusion in the fly-away kits, and which materials may be used as 
ballast.

(h) Minimum Equipment List (MEL) Items

    The master minimum equipment list (MMEL) items specified in 
paragraphs (h)(1) and (2) of this AD are affected by the prohibition 
specified in paragraph (g) of this AD, and therefore may affect the 
operator's existing FAA-approved MEL.
    (1) For Model 737-8, 737-9, and 737-8200 airplanes: MMEL System 
No. 21, Sequence No. 51-02-01, ``Electronic Flow Control.''
    (2) For Model 737-800 and 737-900ER series airplanes: MMEL 
System No. 21, Sequence No. 02-03, ``Electronic Flow Control.''
    Note 2 to paragraph (h): The MMEL items specified in paragraph 
(h) of this AD can be found in the applicable FAA-approved MMEL: 
Boeing 737 (B-737-100/200/300/400/500/600/700/800/900/900ER) MMEL, 
Revision 61, dated July 8, 2020; and Boeing 737 MAX (B-737-8/-8200/-
9) MMEL, Revision 3, dated April 12, 2021. These MMELs can be found 
on the Flight Standards Information Management System (FSIMS) 
website, https://fsims.faa.gov/PICResults.aspx?mode=Publication&doctype=MMELByModel.

(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 Sam Nalbandian, 
Aerospace Engineer, Cabin Safety and Environmental Systems Section, 
FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; 
phone and fax: 206-231-3993; email: [email protected].

(k) Material Incorporated by Reference

    None.

    Issued on July 29, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-16972 Filed 8-5-21; 11:15 am]
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