Airworthiness Directives; The Boeing Company Airplanes

[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 [www.gpo.gov]
[FR Doc No: 2020-11993]


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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.

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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 https://www.regulations.gov. 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 https://www.regulations.gov 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: 
[email protected].

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 https://www.regulations.gov, 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: [email protected].
    (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: [email protected].

(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

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