AD 2020-11-11
Recurring
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 777-200 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-200LR Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-300 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-300ER Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777F Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Discrepancies in the CWT FQIS fuel quantity and the refueling truck uploaded fuel amount could result in an airplane dispatched with insufficient fuel loaded in the CWT and with the flight crew unaware of the insufficient fuel prior to departure. This condition, coupled with continued flight to the destination airport after receiving the EICAS messages while en route to the destination, could result in fuel exhaustion and subsequent power loss of all engines. Thereby, resulting in the inability to land at the destination airport or at a diversion airport, possibly leading to uncontrolled flight into terrain.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
This AD requires a repetitive check of the FQIS fuel quantity calculation and display of the CWT fuel quantity through a new procedure, Refueling Station Door Cycling Procedure, developing a process to provide documentation to the flight crew that this check was done, and revising the existing AFM to incorporate verification procedures for flight crew awareness.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours
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Affected Aircraft
The Boeing Company Model 777 airplanes
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777 airplanes. This AD requires a repetitive check of the fuel quantity indicating system (FQIS) fuel quantity calculation for the center wing tank (CWT) fuel quantity, developing a process to provide documentation to the flight crew that this check was done, and revising the existing airplane flight manual (AFM) to incorporate verification procedures and flight crew awareness. This AD was prompted by reports of discrepancies between the FQIS fuel quantity and the refueling truck uploaded fuel amount, followed by certain engine-indicating and crew-alerting system (EICAS) messages. 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 The Boeing Company Model 777-200, -200LR, -
300, -300ER, and 777F series airplanes, certificated in any
category, equipped with a Center Wing Tank (CWT) having a capacity
of 26,100 U.S. gallons or greater.
Document Text
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[Federal Register Volume 85, Number 107 (Wednesday, June 3, 2020)]
[Rules and Regulations]
[Pages 34090-34094]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2020-11993]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0461; Product Identifier 2020-NM-065-AD; Amendment
39-19915; AD 2020-11-11]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain The Boeing Company Model 777 airplanes. This AD requires a
repetitive check of the fuel quantity indicating system (FQIS) fuel
quantity calculation for the center wing tank (CWT) fuel quantity,
developing a process to provide documentation to the flight crew that
this check was done, and revising the existing airplane flight manual
(AFM) to incorporate verification procedures and flight crew awareness.
This AD was prompted by reports of discrepancies between the FQIS fuel
quantity and the refueling truck uploaded fuel amount, followed by
certain engine-indicating and crew-alerting system (EICAS) messages.
The FAA is issuing this AD to address the unsafe condition on these
products.
DATES: This AD is effective June 18, 2020.
The FAA must receive comments on this AD by July 20, 2020.
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.
Examining the AD Docket
You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2020-
0461; or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday
[[Page 34091]]
through Friday, except Federal holidays. The AD docket contains this
final rule, the regulatory evaluation, any comments received, and other
information. The street address for Docket Operations is listed above.
Comments will be available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Kevin Nguyen, Aerospace Engineer,
Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206-231-3555; email:
<a href="/cdn-cgi/l/email-protection#09626c7f606727676e7c706c67496f6868276e667f"><span class="__cf_email__" data-cfemail="99f2fceff0f7b7f7feece0fcf7d9fff8f8b7fef6ef">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA has received reports involving discrepancies between the
airplane FQIS, specifically the CWT fuel quantity, and the refueling
truck uploaded fuel amount, followed by a FUEL DISAGREE EICAS message
at an early stage of flight (e.g., within 3 hours after take off), and/
or with an INSUFFICIENT FUEL EICAS message. There have been at least 25
in-service events reported by operators. In at least 16 of these
events, the airplanes continued with the mission; of those, 6 landed at
the destination airport, and 10 had to land at a diversion airport.
Insufficient fuel in the CWT as a result of this discrepancy is due to
a design flaw in the FQIS in which the FQIS calibrates incorrect
velocity of sound in the jet fuel during center tank fueling, which
leads to an improper fuel density calculation, and results in the FQIS
showing a different fuel amount from the actual fuel quantity in the
CWT. In almost all of the events, the FQIS showed more fuel than the
actual fuel quantity in the CWT, resulting in less fuel on the airplane
than the required fuel load for the mission. Alternatively, the FQIS
could show less fuel than the actual fuel quantity in the CWT,
resulting in more fuel on the airplane than the required fuel load for
the mission. This issue affects only the CWT and not the main tanks.
There are practical difficulties in comparing the fuel quantity
uploaded by the refueling truck or hydrant. The fueling system relies
on the airplane FQIS to report the mass (kilograms or pounds) of fuel
onboard and stops the fueling process when the requested fuel for the
next flight is onboard. The refueling trucks then report the volume
(liters or gallons) of fuel that was uploaded because fuel is paid for
by a volume measurement. Comparing the fuel volume upload with the
final fuel load mass, which also accounts for the remaining fuel in the
tanks from previous flight, is not an easy calculation and is prone to
significant inaccuracies. The existing airplane maintenance manual and
operator fueling procedures require verification that the correct fuel
amount required for the current mission has been loaded onto the
airplane. The FAA has received reports that verification tasks are
either not accomplished or done incorrectly. As a result, the flight
crew may be unaware of insufficient fuel loaded in the CWT and the
airplane is dispatched for the mission. The airplane onboard fuel
management system typically reports fuel quantity anomalies within the
first three hours of flight resulting in a FUEL DISAGREE EICAS message
and/or an INSUFFICIENT FUEL EICAS message that necessitates fuel check
(e.g., leak check) and fuel quantity monitoring. These messages may
require the flight crew to take action, such as performing an air turn
back or a diversion.
Discrepancies in the CWT FQIS fuel quantity and the refueling truck
uploaded fuel amount could result in an airplane dispatched with
insufficient fuel loaded in the CWT and with the flight crew unaware of
the insufficient fuel prior to departure. This condition, coupled with
continued flight to the destination airport after receiving the EICAS
messages while en route to the destination, could result in fuel
exhaustion and subsequent power loss of all engines. Thereby, resulting
in the inability to land at the destination airport or at a diversion
airport, possibly leading to uncontrolled flight into terrain.
FAA's Determination
The FAA is issuing this AD because the agency evaluated all the
relevant information and determined the unsafe condition described
previously is likely to exist or develop in other products of the same
type design.
AD Requirements
This AD requires a repetitive check of the FQIS fuel quantity
calculation and display of the CWT fuel quantity through a new
procedure, Refueling Station Door Cycling Procedure, developing a
process to provide documentation to the flight crew that this check was
done, and revising the existing AFM to incorporate verification
procedures for flight crew awareness.
Interim Action
The FAA considers this AD interim action. The FAA has been
coordinating with Boeing in the development of a modification that will
address the unsafe condition identified in this AD. However, due to the
urgency of the unsafe condition and due to additional time needed for
Boeing to develop the modification, the FAA has determined that interim
action is necessary. Once the modification is developed, approved, and
available, the FAA might consider additional rulemaking.
FAA's Justification and Determination of the Effective Date
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 waiving notice and comment prior to adoption of this rule
because discrepancies in the CWT FQIS fuel quantity and the refueling
truck uploaded fuel amount could result in an airplane dispatched with
insufficient fuel loaded in the CWT and with the flight crew unaware of
the insufficient fuel prior to departure. This condition, coupled with
continued flight to the destination airport after receiving the EICAS
messages while en route to the destination, could result in fuel
exhaustion and subsequent power loss of all engines. Thereby, resulting
in the inability to land at the destination airport or at a diversion
airport, possibly leading to uncontrolled flight into terrain.
Additionally, the compliance time for the required action is shorter
than the time necessary for the public to comment and for publication
of the final rule. Therefore, the FAA finds good cause that notice and
opportunity for prior public comment are impracticable. In addition,
for the reasons stated above, the FAA finds that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment. However, the FAA invites you to send any written data, views,
or arguments about this final rule. Send your comments to an address
listed under the ADDRESSES section. Include the docket number FAA-2020-
0461 and Product Identifier 2020-NM-065-AD at the beginning of your
comments. The FAA specifically invites comments on the overall
regulatory, economic, environmental, and energy aspects of this final
rule. The FAA will consider all comments received by the closing date
and may amend this final rule because of those comments.
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
[[Page 34092]]
FAA will also post a report summarizing each substantive verbal contact
received about this final rule.
Regulatory Flexibility Act (RFA)
The requirements of the 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 255 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Refueling Station Door Cycling 1 work-hour x $85 $0 $85 per check...... $21,675 per check.
Procedure. per hour = $85 per
check.
AFM revision..................... 1 work-hour x $85 0 $85................ $21,675.
per hour = $85.
----------------------------------------------------------------------------------------------------------------
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 (AD):
2020-11-11 The Boeing Company: Amendment 39-19915; Docket No. FAA-
2020-0461; Product Identifier 2020-NM-065-AD.
(a) Effective Date
This AD is effective June 18, 2020.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 777-200, -200LR, -
300, -300ER, and 777F series airplanes, certificated in any
category, equipped with a Center Wing Tank (CWT) having a capacity
of 26,100 U.S. gallons or greater.
(d) Subject
Air Transport Association (ATA) of America Code 28, Fuel.
(e) Unsafe Condition
The FAA is issuing this AD to address discrepancies in the CWT
fuel quantity indicating system (FQIS) fuel quantity and the
refueling truck uploaded fuel amount, which could result in an
airplane dispatched with insufficient fuel loaded in the CWT and
with the flight crew unaware of the insufficient fuel prior to
departure. This condition, coupled with continued flight to the
destination airport after receiving engine-indicating and crew-
alerting system (EICAS) messages while en route to the destination,
could result in fuel exhaustion and subsequent power loss of all
engines. Thereby, resulting in the inability to land at the
destination airport or at a diversion airport, possibly leading to
uncontrolled flight into terrain.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) CWT Fuel Quantity Check--``Refueling Station Door Cycling
Procedure''
Within 30 days after the effective date of this AD: Check the
fuel quantity of the CWT by doing the ``Refueling Station Door
Cycling Procedure'' as specified in paragraphs (g)(1) through (6) of
this AD. Thereafter, check the fuel quantity of the CWT as specified
in paragraphs (g)(1) through (6) of this AD before further flight
after any center tank fueling (adding or removing fuel).
(1) Get access to the refueling station door and integrated
refuel panel on the left wing.
(2) Close and latch the refueling station door on the left wing
for a minimum of five (5) seconds. If installed, make sure the right
wing refueling station door is closed.
(3) Re-open the refueling station door and wait for the fuel
quantity display to reset.
(4) Make sure that the center or total fuel tank quantities
still remain within fuel load sheet requirements. If the fuel
quantity is incorrect then accomplish actions specified in
paragraphs (g)(4)(i) and (ii) of this AD.
(i) Adjust fuel loading as applicable for fuel upload
parameters. Refer to operator's refuel procedures for adjusting the
fuel load.
(ii) Repeat the ``Refueling Station Door Cycling Procedure,''
starting at paragraph (g)(2) of this AD.
(5) Close the refueling station door.
(6) Notify the operator after the ``Refueling Station Door
Cycling Procedure'' has been done, and correct fuel load verified.
(h) Process To Provide Documentation to the Flight Crew
Within 30 days after the effective date of this AD, submit a
process to the FAA (Flight Standards) for approval that describes at
the end of the fueling process and before each flight how
documentation is provided to the flight crew that the CWT fuel
quantity check using the ``Refueling Station Door Cycling
Procedure'' specified in paragraph (g) of this AD was done.
(i) Airplane Flight Manual (AFM) Revision Requiring Flight Crew
Verification
(1) Within 30 days after the effective date of this AD: Revise
the ``Certificate Limitations: Fuel Quantity Indication System
[[Page 34093]]
(FQIS)'' section of the operator's existing AFM by incorporating the
information specified in figure 1 to paragraph (i)(1) of this AD.
[GRAPHIC] [TIFF OMITTED] TR03JN20.013
(2) Within 30 days after the effective date of this AD: Revise
the ``Normal Procedures: Fuel Quantity Indication System (FQIS)--
Refueling Station Door Cycling Procedure'' section of the operator's
existing AFM by incorporating the information specified in figure 2
to paragraph (i)(2) of this AD.
BILLING CODE 4910-13-P
[[Page 34094]]
[GRAPHIC] [TIFF OMITTED] TR03JN20.014
(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 local Flight Standards District
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 (k) of this AD. Information may be
emailed to: <a href="/cdn-cgi/l/email-protection#ebd2c6aaa5a6c6b88e8a9f9f878ec6aaa8a4c6aaa6a4a8c6b98e9a9e8e989f98ab8d8a8ac58c849d"><span class="__cf_email__" data-cfemail="1c25315d5251314f797d68687079315d5f53315d51535f314e796d69796f686f5c7a7d7d327b736a">[email protected]</span></a>.
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district 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 Kevin Nguyen,
Aerospace Engineer, Propulsion Section, FAA, Seattle ACO Branch,
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3555; email: <a href="/cdn-cgi/l/email-protection#066d63706f68286861737f63684660676728616970"><span class="__cf_email__" data-cfemail="d0bbb5a6b9befebeb7a5a9b5be90b6b1b1feb7bfa6">[email protected]</span></a>.
(l) Material Incorporated by Reference
None.
Issued on May 28, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2020-11993 Filed 5-29-20; 4:15 pm]
BILLING CODE 4910-13-C
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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