Airworthiness Directives; The Boeing Company Airplanes, 72902-72904 [2022-25722]
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72902
Federal Register / Vol. 87, No. 227 / Monday, November 28, 2022 / Proposed Rules
(4) You may view this service information
at the FAA, Office of the Regional Counsel,
Southwest Region, 10101 Hillwood Pkwy.,
Room 6N–321, Fort Worth, TX 76177. For
information on the availability of this
material at the FAA, call (817) 222–5110.
(5) You may view this service information
that is incorporated by reference at the
National Archives and Records
Administration (NARA). For information on
the availability of this material at NARA,
email: fr.inspection@nara.gov), or go to:
www.archives.gov/federal-register/cfr/ibrlocations.html.
Issued on November 18, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2022–25709 Filed 11–25–22; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2022–1063; Project
Identifier AD–2021–01339–T]
RIN 2120–AA64
Airworthiness Directives; The Boeing
Company Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
The FAA proposes to adopt a
new airworthiness directive (AD) for
certain The Boeing Company Model
737–8, 737–9, and 737–8200 airplanes.
This proposed AD was prompted by a
determination that a new airworthiness
limitation is necessary to require
periodic replacement of the oxygen
sensor of the nitrogen generation system
(NGS). This proposed AD would require
revising the existing maintenance or
inspection program, as applicable, to
incorporate the new airworthiness
limitation. 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 January 12,
2023.
SUMMARY:
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,
khammond on DSKJM1Z7X2PROD with PROPOSALS
ADDRESSES:
VerDate Sep<11>2014
19:29 Nov 25, 2022
Jkt 259001
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.
For service information identified in
this NPRM, contact Boeing Commercial
Airplanes, Attention: Contractual & Data
Services (C&DS), 2600 Westminster
Blvd., 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.
Examining the AD Docket
You may examine the AD docket at
regulations.gov by searching for and
locating Docket No. FAA–2022–1063; 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.
FOR FURTHER INFORMATION CONTACT:
Chris Baker, Aerospace Engineer,
Propulsion Section, FAA, Seattle ACO
Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206–
231–3552; email: christopher.r.baker@
faa.gov.
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–2022–1063; Project Identifier AD–
2021–01339–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
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Sfmt 4702
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 Chris Baker,
Aerospace Engineer, Propulsion
Section, FAA, Seattle ACO Branch, 2200
South 216th St., Des Moines, WA 98198;
phone and fax: 206–231–3552; email:
christopher.r.baker@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.
Background
This proposed AD was prompted by
the discovery of a safety issue related to
the reliability of the oxygen sensor of
the airplane’s NGS.
The NGS is an onboard inert gas
system that reduces the flammability of
the airplane’s center fuel tank. The NGS
uses an air separation module (ASM) to
separate oxygen and nitrogen from the
air. The ASM uses input from an oxygen
sensor. After the ASM separates the
oxygen-enriched air from the nitrogenenriched air, the NGS returns nitrogenenriched air to the fuel tank, and vents
the oxygen-enriched air overboard.
These actions reduce the flammability
of the fuel tank.
Boeing discovered that the oxygen
sensor’s reliability can degrade over
time. Degraded performance by the
sensor could result in the ASM failing
to produce nitrogen-enriched air, and
the fuel tank becoming more flammable
due to excessive oxygen-enriched air.
Such additional flammability, if
coupled with an ignition source in the
fuel tank, could lead to a fuel tank
explosion. This proposed AD would
require adding an airworthiness
limitation to require periodic
replacement of the oxygen sensor.
This proposed AD would apply to
airplanes with an original airworthiness
certificate or original export certificate
of airworthiness issued on or before
April 1, 2021, as well as airplanes with
line numbers 7668, 7678, and 7915.
Boeing did not start delivering airplanes
with Boeing 737–7/8/8200/9/10 Special
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Federal Register / Vol. 87, No. 227 / Monday, November 28, 2022 / Proposed Rules
Compliance Items/Airworthiness
Limitations, D626A011–9–04, dated
January 2019, which addresses this
issue, until after April 1, 2021, and
delivered airplanes with line numbers
7668, 7678, and 7915 with an earlier
revision of that document. The
applicability in this proposed AD is
therefore limited to airplanes that were
delivered with a version of Boeing 737–
7/8/8200/9/10 Special Compliance
Items/Airworthiness Limitations,
D626A011–9–04 dated prior to January
2019.
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.
khammond on DSKJM1Z7X2PROD with PROPOSALS
Related Service Information Under 1
CFR Part 51
The FAA reviewed Boeing 737–7/8/
8200/9/10 Special Compliance Items/
Airworthiness Limitations, D626A011–
9–04, dated January 2019. This service
information describes, among other
airworthiness limitations (AWLs),
airworthiness limitation instruction
(ALI) AWL No. 47–AWL–09, ‘‘Nitrogen
Generation System—Oxygen Sensor,’’
for replacing oxygen sensors. 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 the ADDRESSES section.
Proposed AD Requirements in This
NPRM
This proposed AD would require
revising the existing maintenance or
inspection program, as applicable, to
incorporate a new airworthiness
limitation.
This proposed AD would require
revisions to certain operator
maintenance documents to include new
actions (replacements). Compliance
with these actions is required by 14 CFR
91.403(c). For airplanes that have been
previously modified, altered, or repaired
in the areas addressed by this proposed
AD, the operator may not be able to
accomplish the actions described in the
revisions. In this situation, to comply
with 14 CFR 91.403(c), the operator
must request approval for an alternative
method of compliance according to
paragraph (i) of this proposed AD.
Costs of Compliance
The FAA estimates that this AD, if
adopted as proposed, would affect 62
airplanes of U.S. registry. The FAA
estimates the following costs to comply
with this proposed AD:
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19:29 Nov 25, 2022
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The FAA has determined that revising
the existing maintenance or inspection
program takes an average of 90 workhours per operator, although the agency
recognizes that this number may vary
from operator to operator. Since
operators incorporate maintenance or
inspection program changes for their
affected fleet(s), 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 × $85 per workhour).
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.
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72903
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
1. The authority citation for part 39
continues to read as follows:
■
Authority: 49 U.S.C. 106(g), 40113, 44701.
§ 39.13
[Amended]
2. The FAA amends § 39.13 by adding
the following new airworthiness
directive:
■
The Boeing Company: Docket No. FAA–
2022–1063; Project Identifier AD–2021–
01339–T.
(a) Comments Due Date
The FAA must receive comments on this
airworthiness directive (AD) by January 12,
2023.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company
Model 737–8, 737–9, and 737–8200
airplanes, certificated in any category,
identified in paragraphs (c)(1) and (2) of this
AD.
(1) Airplanes with an original
airworthiness certificate or original export
certificate of airworthiness issued on or
before April 1, 2021.
(2) Airplanes with line numbers 7668,
7678, and 7915.
(d) Subject
Air Transport Association (ATA) of
America Code 28, Fuel.
(e) Unsafe Condition
This AD was prompted by significant
changes made to an airworthiness limitation
(AWL) related to the nitrogen generation
system (NGS). The FAA is issuing this AD to
prevent increasing the flammability exposure
of the center fuel tank, which together with
an ignition source in the fuel tank, could lead
to a fuel tank explosion and consequent loss
of the airplane.
(f) Compliance
Comply with this AD within the
compliance times specified, unless already
done.
(g) Maintenance or Inspection Program
Revision
Within 60 days after the effective date of
this AD, revise the existing maintenance or
inspection program, as applicable, to
incorporate the information specified in
AWL No. 47–AWL–09, ‘‘Nitrogen Generation
System—Oxygen Sensor,’’ of Boeing 737–7/
8/8200/9/10 Special Compliance Items/
Airworthiness Limitations, D626A011–9–04,
dated January 2019. The initial compliance
time for the airworthiness limitation
instruction (ALI) task is: Within 18,000 flight
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Federal Register / Vol. 87, No. 227 / Monday, November 28, 2022 / Proposed Rules
hours after the date of issuance of the original
airworthiness certificate or the original
export certificate of airworthiness, within
18,000 flight hours after the most recent
replacement was performed as specified in
AWL No. 47–AWL–09, or within 12 months
after the effective date of this AD, whichever
is latest.
Issued on August 19, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness
Division, Aircraft Certification Service.
(h) No Alternative Actions or Intervals
DEPARTMENT OF TRANSPORTATION
After the existing maintenance or
inspection program has been revised as
required by paragraph (g) of this AD, no
alternative actions (e.g., inspections) or
intervals may be used unless the actions and
intervals are approved as an alternative
method of compliance (AMOC) in
accordance with the procedures specified in
paragraph (i) of this AD.
Federal Aviation Administration
(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 paragraph (j)(1) of
this AD. Information may be emailed to: 9ANM-Seattle-ACO-AMOC-Requests@faa.gov.
(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.
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(j) Related Information
(1) For more information about this AD,
contact Chris Baker, Aerospace Engineer,
Propulsion Section, FAA, Seattle ACO
Branch, 2200 South 216th St., Des Moines,
WA 98198; phone and fax: 206–231–3552;
email: christopher.r.baker@faa.gov.
(2) 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; internet
myboeingfleet.com. You may view this
referenced 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.
VerDate Sep<11>2014
19:29 Nov 25, 2022
Jkt 259001
[FR Doc. 2022–25722 Filed 11–25–22; 8:45 am]
BILLING CODE 4910–13–P
14 CFR Part 71
[Docket No. FAA–2022–1424; Airspace
Docket No. 22–AEA–11]
RIN 2120–AA66
Proposed Amendment of VOR Federal
Airways V–268 and V–474, Revocation
of Jet Route J–518 and VOR Federal
Airway V–119, and Establishment of
Area Navigation Route Q–178 in the
Vicinity of Indian Head, PA
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
This action proposes to
amend VHF Omnidirectional Range
(VOR) Federal airways V–268 and
V–474, revoke Jet Route J–518 and VOR
Federal airway V–119, and establish
Area Navigation (RNAV) route Q–178.
The FAA is proposing this action due to
the planned decommissioning of the
VOR portion of the Indian Head, PA,
VOR/Tactical Air Navigation (VORTAC)
navigational aid (NAVAID). The Indian
Head VOR is being decommissioned in
support of the FAA’s VOR Minimum
Operational Network (MON) program.
DATES: Comments must be received on
or before January 12, 2023.
ADDRESSES: Send comments on this
proposal to the U.S. Department of
Transportation, Docket Operations, 1200
New Jersey Avenue SE, West Building
Ground Floor, Room W12–140,
Washington, DC 20590; telephone:
1(800) 647–5527, or (202) 366–9826.
You must identify FAA Docket No.
FAA–2022–1424; Airspace Docket No.
22–AEA–11 at the beginning of your
comments. You may also submit
comments through the internet at
www.regulations.gov.
FAA Order JO 7400.11G, Airspace
Designations and Reporting Points, and
subsequent amendments can be viewed
online at www.faa.gov/air_traffic/
publications/. For further information,
you can contact the Rules and
Regulations Group, Federal Aviation
Administration, 800 Independence
Avenue SW, Washington, DC 20591;
telephone: (202) 267–8783.
SUMMARY:
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FOR FURTHER INFORMATION CONTACT:
Colby Abbott, Rules and Regulations
Group, Office of Policy, Federal
Aviation Administration, 800
Independence Avenue SW, Washington,
DC 20591; telephone: (202) 267–8783.
SUPPLEMENTARY INFORMATION:
Authority for This Rulemaking
The FAA’s authority to issue rules
regarding aviation safety is found in
Title 49 of the United States Code.
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. This rulemaking is
promulgated under the authority
described in Subtitle VII, Part A,
Subpart I, Section 40103. Under that
section, the FAA is charged with
prescribing regulations to assign the use
of the airspace necessary to ensure the
safety of aircraft and the efficient use of
airspace. This regulation is within the
scope of that authority as it would
modify the National Airspace System
(NAS) as necessary to preserve the safe
and efficient flow of air traffic.
Comments Invited
Interested parties are invited to
participate in this proposed rulemaking
by submitting such written data, views,
or arguments as they may desire.
Comments that provide the factual basis
supporting the views and suggestions
presented are particularly helpful in
developing reasoned regulatory
decisions on the proposal. Comments
are specifically invited on the overall
regulatory, aeronautical, economic,
environmental, and energy-related
aspects of the proposal.
Communications should identify both
docket numbers (FAA Docket No. FAA–
2022–1424 Airspace; Docket No. 22–
AEA–11) and be submitted in triplicate
to the Docket Management Facility (see
ADDRESSES section for address and
phone number). You may also submit
comments through the internet at
www.regulations.gov.
Commenters wishing the FAA to
acknowledge receipt of their comments
on this action must submit with those
comments a self-addressed, stamped
postcard on which the following
statement is made: ‘‘Comments to FAA
Docket No. FAA–2022–1424; Airspace
Docket No. 22–AEA–11.’’ The postcard
will be date/time stamped and returned
to the commenter.
All communications received on or
before the specified comment closing
date will be considered before taking
action on the proposed rule. The
proposal contained in this action may
be changed in light of comments
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]]>Agencies
[Federal Register Volume 87, Number 227 (Monday, November 28, 2022)]
[Proposed Rules]
[Pages 72902-72904]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-25722]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2022-1063; Project Identifier AD-2021-01339-T]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain The Boeing Company Model 737-8, 737-9, and 737-8200
airplanes. This proposed AD was prompted by a determination that a new
airworthiness limitation is necessary to require periodic replacement
of the oxygen sensor of the nitrogen generation system (NGS). This
proposed AD would require revising the existing maintenance or
inspection program, as applicable, to incorporate the new airworthiness
limitation. 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 January 12,
2023.
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.
For service information identified in this NPRM, contact Boeing
Commercial Airplanes, Attention: Contractual & Data Services (C&DS),
2600 Westminster Blvd., 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.
Examining the AD Docket
You may examine the AD docket at regulations.gov by searching for
and locating Docket No. FAA-2022-1063; 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.
FOR FURTHER INFORMATION CONTACT: Chris Baker, Aerospace Engineer,
Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206-231-3552; 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-2022-1063; Project Identifier
AD-2021-01339-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 Chris
Baker, Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch,
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3552; 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
This proposed AD was prompted by the discovery of a safety issue
related to the reliability of the oxygen sensor of the airplane's NGS.
The NGS is an onboard inert gas system that reduces the
flammability of the airplane's center fuel tank. The NGS uses an air
separation module (ASM) to separate oxygen and nitrogen from the air.
The ASM uses input from an oxygen sensor. After the ASM separates the
oxygen-enriched air from the nitrogen-enriched air, the NGS returns
nitrogen-enriched air to the fuel tank, and vents the oxygen-enriched
air overboard. These actions reduce the flammability of the fuel tank.
Boeing discovered that the oxygen sensor's reliability can degrade
over time. Degraded performance by the sensor could result in the ASM
failing to produce nitrogen-enriched air, and the fuel tank becoming
more flammable due to excessive oxygen-enriched air. Such additional
flammability, if coupled with an ignition source in the fuel tank,
could lead to a fuel tank explosion. This proposed AD would require
adding an airworthiness limitation to require periodic replacement of
the oxygen sensor.
This proposed AD would apply to airplanes with an original
airworthiness certificate or original export certificate of
airworthiness issued on or before April 1, 2021, as well as airplanes
with line numbers 7668, 7678, and 7915. Boeing did not start delivering
airplanes with Boeing 737-7/8/8200/9/10 Special
[[Page 72903]]
Compliance Items/Airworthiness Limitations, D626A011-9-04, dated
January 2019, which addresses this issue, until after April 1, 2021,
and delivered airplanes with line numbers 7668, 7678, and 7915 with an
earlier revision of that document. The applicability in this proposed
AD is therefore limited to airplanes that were delivered with a version
of Boeing 737-7/8/8200/9/10 Special Compliance Items/Airworthiness
Limitations, D626A011-9-04 dated prior to January 2019.
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 737-7/8/8200/9/10 Special Compliance Items/
Airworthiness Limitations, D626A011-9-04, dated January 2019. This
service information describes, among other airworthiness limitations
(AWLs), airworthiness limitation instruction (ALI) AWL No. 47-AWL-09,
``Nitrogen Generation System--Oxygen Sensor,'' for replacing oxygen
sensors. 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 the ADDRESSES section.
Proposed AD Requirements in This NPRM
This proposed AD would require revising the existing maintenance or
inspection program, as applicable, to incorporate a new airworthiness
limitation.
This proposed AD would require revisions to certain operator
maintenance documents to include new actions (replacements). Compliance
with these actions is required by 14 CFR 91.403(c). For airplanes that
have been previously modified, altered, or repaired in the areas
addressed by this proposed AD, the operator may not be able to
accomplish the actions described in the revisions. In this situation,
to comply with 14 CFR 91.403(c), the operator must request approval for
an alternative method of compliance according to paragraph (i) of this
proposed AD.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 62 airplanes of U.S. registry. The FAA estimates the following
costs to comply with this proposed AD:
The FAA has determined that revising the existing maintenance or
inspection program takes an average of 90 work-hours per operator,
although the agency recognizes that this number may vary from operator
to operator. Since operators incorporate maintenance or inspection
program changes for their affected fleet(s), 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
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-2022-1063; Project Identifier AD-
2021-01339-T.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by January 12, 2023.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 737-8, 737-9, and
737-8200 airplanes, certificated in any category, identified in
paragraphs (c)(1) and (2) of this AD.
(1) Airplanes with an original airworthiness certificate or
original export certificate of airworthiness issued on or before
April 1, 2021.
(2) Airplanes with line numbers 7668, 7678, and 7915.
(d) Subject
Air Transport Association (ATA) of America Code 28, Fuel.
(e) Unsafe Condition
This AD was prompted by significant changes made to an
airworthiness limitation (AWL) related to the nitrogen generation
system (NGS). The FAA is issuing this AD to prevent increasing the
flammability exposure of the center fuel tank, which together with
an ignition source in the fuel tank, could lead to a fuel tank
explosion and consequent loss of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Maintenance or Inspection Program Revision
Within 60 days after the effective date of this AD, revise the
existing maintenance or inspection program, as applicable, to
incorporate the information specified in AWL No. 47-AWL-09,
``Nitrogen Generation System--Oxygen Sensor,'' of Boeing 737-7/8/
8200/9/10 Special Compliance Items/Airworthiness Limitations,
D626A011-9-04, dated January 2019. The initial compliance time for
the airworthiness limitation instruction (ALI) task is: Within
18,000 flight
[[Page 72904]]
hours after the date of issuance of the original airworthiness
certificate or the original export certificate of airworthiness,
within 18,000 flight hours after the most recent replacement was
performed as specified in AWL No. 47-AWL-09, or within 12 months
after the effective date of this AD, whichever is latest.
(h) No Alternative Actions or Intervals
After the existing maintenance or inspection program has been
revised as required by paragraph (g) of this AD, no alternative
actions (e.g., inspections) or intervals may be used unless the
actions and intervals are approved as an alternative method of
compliance (AMOC) in accordance with the procedures specified in
paragraph (i) of this AD.
(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 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, 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
(1) For more information about this AD, contact Chris Baker,
Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch,
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3552; email: [email protected].
(2) 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; internet myboeingfleet.com. You may
view this referenced 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.
Issued on August 19, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2022-25722 Filed 11-25-22; 8:45 am]
BILLING CODE 4910-13-P
