AD 2021-06-03
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | Various | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
A water supply line that detached at a certain joint located above an electronic equipment (EE) cooling filter, leading to water intrusion into the forward EE bay.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Deactivate the potable water system.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
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Affected Aircraft
The Boeing Company Model 777F series airplanes, line numbers (L/Ns) 960 and subsequent.
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Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 777F series airplanes. This AD was prompted by a report of a water supply line that detached at a certain joint located above an electronic equipment (EE) cooling filter, leading to water intrusion into the forward EE bay. This AD requires deactivating the potable water system. The FAA is issuing this AD to address the unsafe condition on these products.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to all The Boeing Company Model 777F series
airplanes, certificated in any category.
Document Text
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[Federal Register Volume 86, Number 42 (Friday, March 5, 2021)]
[Rules and Regulations]
[Pages 12809-12812]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-04713]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0133; Project Identifier AD-2021-00234-T;
Amendment 39-21469; AD 2021-06-03]
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 777F series airplanes. This AD was prompted by
a report of a water supply line that detached at a certain joint
located above an electronic equipment (EE) cooling filter, leading to
water intrusion into the forward EE bay. This AD requires deactivating
the potable water system. The FAA is issuing this AD to address the
unsafe condition on these products.
DATES: This AD is effective March 5, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 5,
2021.
The FAA must receive comments on this AD by April 19, 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a>. 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.
For service information identified in this final rule, 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 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
[[Page 12810]]
material at the FAA, call 206-231-3195. It is also available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2021-
0133.
Examining the AD Docket
You may examine the AD docket at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by
searching for and locating Docket No. FAA-2021-0133; 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 the
Docket Operations is listed above.
FOR FURTHER INFORMATION CONTACT: Courtney Kronenberger, Aerospace
Engineer, Cabin Safety and Environmental Systems Section, FAA, Seattle
ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax:
206-231-3986; email: <a href="/cdn-cgi/l/email-protection#23604c5651574d465a0d620d68514c4d464d414651444651634542420d444c55"><span class="__cf_email__" data-cfemail="d794b8a2a5a3b9b2aef996f99ca5b8b9b2b9b5b2a5b0b2a597b1b6b6f9b0b8a1">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Background
The FAA has received a report of a water supply line that detached
above an EE cooling filter, leading to water intrusion into the forward
EE bay, on a Model 777F series airplane with 34,000 total flight hours
and 6,000 total flight cycles.
During potable water servicing on ground, the operator received
multiple messages appearing on the engine indication and crew alert
system (EICAS) indicating multiple affected EE line replaceable units
(LRUs). Further investigation revealed that the location of a joint on
a swaged end fitting ferrule of a corrosion resistant stainless steel
(CRES) water supply line had become partially or fully detached from
the tube, causing water to spill onto an EE cooling filter (directly
below the fitting) in the left-hand sidewall at station (STA) 571. The
amount and duration of the water spillage are unknown. The cooling
filter became saturated with the water, which was then blown via the EE
cooling system into multiple EE LRUs located in the EE bay.
Water that has been ingested or has entered into the EE cooling
system via the cooling filter can be circulated to multiple EE racks
and can accumulate on the LRUs, particularly where forced air cooling
occurs. Water ingress to these LRUs can affect multiple EE bay racks
and LRUs, resulting in loss of functionality or inaccurate output of
critical electrical systems and possible loss of control of the
airplane. The FAA is issuing this AD to address the unsafe condition on
these products.
Model 777F series airplanes line numbers (L/Ns) 960 and subsequent
have a joint at this location from the factory-installed CRES tube
assembly. Boeing released Service Bulletin 777-38-0042 as an economic
service bulletin providing operators with airplanes prior to L/N 960
instructions to retrofit to this configuration at their discretion.
Therefore, this AD will require deactivation of the potable water
system for all 777F with this joint installed either in production or
through performance of Boeing SB 777-38-0042.
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.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Boeing MOM-MOM-21-0089-01B, dated February 26,
2021. This service information specifies procedures for deactivating
the potable water system. 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.
AD Requirements
This AD requires accomplishing the actions specified in the service
information already described, except as discussed under ``Differences
Between this AD and the Service Information.'' This AD also prohibits
the future accomplishment of the actions specified in Boeing Service
Bulletin 777-38-0042.
Difference Between This AD and the Service Information
Boeing MOM-MOM-21-0089-01B, dated February 26, 2021, specifies one
Safety Action and six Recommended Actions. Although the FAA recommends
accomplishment of all of these actions, this AD requires only
deactivation of the potable water system, as specified in the Safety
Action of the service information.
Interim Action
The FAA considers this AD to be an interim action. The manufacturer
is currently developing a modification that will address the unsafe
condition identified in this AD. Once this modification is developed,
approved, and available, the FAA might consider additional rulemaking.
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. The FAA has found that the risk to the flying public
justifies forgoing notice and comment prior to adoption of this rule
because water that has entered the EE cooling system via the cooling
filter can affect multiple EE bay racks and LRUs, resulting in loss of
functionality or inaccurate output of critical electrical systems and
possible loss of control of the airplane. 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-2021-0133 and Project Identifier AD-
2021- 00234-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
<a href="https://www.regulations.gov">https://www.regulations.gov</a>, including any personal information you
provide. The agency will also post a report
[[Page 12811]]
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
Courtney Kronenberger, Aerospace Engineer, Cabin Safety and
Environmental Systems Section, FAA, Seattle ACO Branch, 2200 South
216th St., Des Moines, WA 98198; phone and fax: 206-231-3986; email:
<a href="/cdn-cgi/l/email-protection#0b48647e797f656e72254a25407964656e65696e796c6e794b6d6a6a256c647d"><span class="__cf_email__" data-cfemail="93d0fce6e1e7fdf6eabdd2bdd8e1fcfdf6fdf1f6e1f4f6e1d3f5f2f2bdf4fce5">[email protected]</span></a>. 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 58 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
----------------------------------------------------------------------------------------------------------------
Deactivation of potable water system.. 2 work-hours x $85 per $0 $170 $9,860
hour = $170.
----------------------------------------------------------------------------------------------------------------
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:
2021-06-03 The Boeing Company: Amendment 39-21469; Docket No. FAA-
2021-0133; Project Identifier AD-2021-00234-T.
(a) Effective Date
This airworthiness directive (AD) is effective March 5, 2021.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 777F series
airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 38, Water/waste.
(e) Unsafe Condition
This AD was prompted by a report of a water supply line that
detached above an electronic equipment (EE) cooling filter, leading
to water intrusion into the forward EE bay. The FAA is issuing this
AD to address water entering the EE cooling system via the cooling
filter, which can affect multiple EE bay racks and line replaceable
units (LRUs), resulting in loss of functionality or inaccurate
output of critical electrical systems and possible loss of control
of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Deactivation of Potable Water System
For the airplanes identified in paragraphs (g)(1) and (2) of
this AD: Within 5 days after the effective date of this AD,
deactivate the potable water system, in accordance with Boeing Multi
Operator Message MOM-MOM-21-0089-01B, dated February 26, 2021 (MOM-
MOM-21-0089-01B).
(1) Line numbers (L/Ns) 959 and earlier on which the actions
specified in Boeing Service Bulletin 777-38-0042 have been
accomplished.
(2) L/Ns 960 and subsequent.
Note 1 to paragraph (g): Guidance on deactivating the potable
water system can be found in Boeing 777 Aircraft Maintenance Manual
(AMM) Task 38-10-00-040-801.
(h) Installation Prohibition
For airplanes not identified in paragraph (g) of this AD: As of
the effective date of this AD, accomplishment of the actions
specified in Boeing Service Bulletin 777-38-0042 is prohibited.
[[Page 12812]]
(i) Reporting Provisions
Although Boeing MOM-MOM-21-0089-01B specifies to report
inspection findings, this AD does not require any report.
(j) 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: <a href="/cdn-cgi/l/email-protection#023b2f434c4f2f51676376766e672f43414d2f434f4d412f5067737767717671426463632c656d74"><span class="__cf_email__" data-cfemail="11283c505f5c3c42747065657d743c50525e3c505c5e523c4374606474626562517770703f767e67">[email protected]</span></a>.
(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.
(k) Related Information
For more information about this AD, contact Courtney
Kronenberger, Aerospace Engineer, Cabin Safety and Environmental
Systems Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206-231-3986; email:
<a href="/cdn-cgi/l/email-protection#43002c3631372d263a6d026d08312c2d262d212631242631032522226d242c35"><span class="__cf_email__" data-cfemail="b7f4d8c2c5c3d9d2ce99f699fcc5d8d9d2d9d5d2c5d0d2c5f7d1d6d699d0d8c1">[email protected]</span></a>.
(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 Multi Operator Message MOM-MOM-21-0089-01B, dated
February 26, 2021.
(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; internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(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 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 <a href="/cdn-cgi/l/email-protection#adcbc8c9dfc8ca83c1c8caccc1edc3ccdfcc83cac2db"><span class="__cf_email__" data-cfemail="36505352445351185a5351575a765857445718515940">[email protected]</span></a>, or go to <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued on March 2, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2021-04713 Filed 3-3-21; 11:15 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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