[Federal Register Volume 89, Number 195 (Tuesday, October 8, 2024)]
[Rules and Regulations]
[Pages 81314-81320]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-23117]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-0769; Project Identifier AD-2023-00556-T;
Amendment 39-22815; AD 2024-16-09]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain The Boeing Company Model 777-200, -200LR, -300, -300ER, and
777F series airplanes. This AD was prompted by a report indicating
multiple findings of cracks in the fuselage skin common to the
underwing longeron (UWL). This AD requires external or internal
(depending on configuration) inspections for any cracking of the left
and right side fuselage skin common to the UWL, and applicable on-
condition actions. The FAA is issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective November 12, 2024.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of November 12,
2024.
ADDRESSES:
[[Page 81315]]
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-0769; 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 address for Docket Operations is U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
Material Incorporated by Reference:
For Boeing material 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; website myboeingfleet.com.
You may view this material 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. It is also available at regulations.gov under
Docket No. FAA-2024-0769.
FOR FURTHER INFORMATION CONTACT: Luis Cortez-Muniz, Aviation Safety
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-
231-3958; email: [email protected].
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain The Boeing
Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes.
The NPRM published in the Federal Register on March 28, 2024 (89 FR
21446). The NPRM was prompted by a report indicating multiple findings
of cracks in the fuselage skin common to the UWL. In the NPRM, the FAA
proposed to require external or internal (depending on configuration)
inspections for any cracking of the left and right side fuselage skin
common to the UWL, and applicable on-condition actions. The FAA is
issuing this AD to address fuselage skin cracking caused by cold work
surface upset that is not removed from the mating parts and high joint
load transfer or significant local bending stresses at critical
fastener locations. The unsafe condition, if not addressed, could
result in an inability of a principal structural element (PSE) to
sustain limit load, leading to reduced structural integrity of the
airplane and possible loss of control of the airplane.
Discussion of Final Airworthiness Directive
Comments
The FAA received a comment from FedEx Express, who found no issues
that could interfere with the timely implementation of the proposed
actions in the NPRM.
The FAA received additional comments from three commenters,
including American Airlines, Boeing, and United Airlines. The following
presents the comments received on the NPRM and the FAA's response to
each comment.
Request To Clarify Locations Specified in Paragraph (h)(3) of the
Proposed AD
Boeing requested that paragraph (h)(3) of the proposed AD be
clarified to specify that only the fuel tank side of fastener locations
that penetrate the fuel tank boundary require cap seal dimensions to
meet the dimensions given in Figure 1 to paragraph (h)(3) of the
proposed AD. Boeing stated that the service information referenced in
Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16,
2023, contain instructions for applying cap seals to fasteners that
penetrate a fuel tank boundary and fasteners that do not penetrate a
fuel tank boundary. Boeing added that for fasteners that do not
penetrate a fuel tank boundary, fastener sealing is used as a pressure
seal to help mitigate corrosion and have sealing specifications that
include minimum thickness requirements less than the amount shown in
paragraph (h)(3) of the proposed AD that are acceptable for their
intended function outside of the fuel tank. Boeing stated that for
fasteners that penetrate the fuel tank, the cap seals on the interior
side of the fuel tank act as a primary fuel seal, providing fault
tolerance against electromagnetic effects (electrical fault currents
and lightning currents), and are also cap sealed on the exterior side
for corrosion prevention.
Boeing concluded that only the cap seals on the interior side of
the fuel tank require the dimensions specified in Figure 1 of paragraph
(h)(3) of the proposed AD to perform their intended function, which is
consistent with the labels shown in Figure 1 of paragraph (h)(3) of the
proposed AD. Boeing recommended replacing the text ``applying a cap
seal (sealant) to a fastener, fastener head, and fastener threads and
collars, for this AD, during application of any cap seal to a fastener,
fastener head, or fastener threads and collars'' with the text
``applying a cap seal (sealant) to a fastener location that penetrates
the fuel tank boundary, for this AD, during application of any cap seal
to a fastener, fastener head, or fastener threads and collars inside
the fuel tank.''
The FAA agrees to clarify paragraph (h)(3) of this AD for the
reasons provided by the commenter. Locations that do not penetrate the
fuel tank boundary do not require the same sealant application
procedures. The FAA has added the text ``inside the fuel tank'' to
paragraph (h)(3) of this AD. However, the FAA did not replace the text
``to a fastener, fastener head, and fastener threads and collars'' with
the text ``to a fastener location that penetrates the fuel tank
boundary,'' as recommended by the commenter, because the text ``to a
fastener, fastener head, and fastener threads and collars inside the
fuel tank'' better aligns with the language within the service
information.
Request To Clarify Service Information in Paragraph (h)(3) of the
Proposed AD
American Airlines requested that the FAA provided a comprehensive
list of all service information that will be impacted by paragraph
(h)(3) of the proposed AD. American Airlines stated that the statement
``Where any service information referenced in Boeing Alert Requirements
Bulletin 777-53A0100 RB'' is vague and could potentially lead to
confusion.
The FAA agrees to specify the service information affected by
paragraph (h)(3) of this AD. In addition, the FAA notes that paragraph
(h)(2) of this AD has similar language (``Where . . . any service
information referenced in Boeing Alert Requirements Bulletin 777-
53A0100 RB''). The FAA has added a note to paragraphs (h)(2) and (3) of
this AD to specify that Boeing Alert Requirements Bulletin 777-53A0100
RB, dated March 16, 2023, refers to Boeing Service Bulletin 777-53-
0084, Revision 2, dated December 9, 2020; Boeing Service Bulletin 777-
53-0087, Revision 1, dated March 4, 2020; and Boeing Alert Requirements
Bulletin 777-57A0122 RB, dated October 8, 2021.
Request To Add a Note to Paragraph (h)(3) of the Proposed AD
Boeing requested that the FAA add a note to paragraph (h)(3) of the
proposed AD to refer to Boeing Model 777 Aircraft Maintenance Manual
(AMM) section 28-11-00 as an acceptable cap sealing procedure to
accomplish the actions required in that paragraph. Boeing stated it has
received numerous queries from operators on Figure 1 to paragraph
(h)(4) of AD 2023-17-14, which is identical to Figure 1 to paragraph
(h)(3)
[[Page 81316]]
of the proposed AD. Operators have asked whether Boeing Model 777 AMM
section 28-11-00 would be an acceptable procedure for accomplishing the
requirements of paragraph (h)(4) of AD 2023-17-14. Boeing stated it
believes that AMM 28-11-00 is an acceptable procedure for performing
cap sealing inside the fuel tank because the AMM is the source material
for the contents in Figure 1 to paragraph (h)(3) of the proposed AD and
contains the same minimum seal thickness dimensions as shown in Figure
1.
The FAA agrees. Boeing 777 AMM 28-11-00 meets the sealant
requirements of Figure 1 to paragraph (h)(3) of this AD. As such, it
would be an acceptable procedure to follow when sealing inside the fuel
tank in accordance with paragraph (h)(3) of this AD. The FAA has added
a note to paragraph (h)(3) of this AD accordingly.
Request for Removal of Certain Exceptions That Are Related to Other ADs
United Airlines (United) requested removal of the exceptions in
paragraphs (h)(4) through (6) of the proposed AD that are for service
information other than Boeing Alert Requirements Bulletin 777-53A0100
RB, dated March 16, 2023. United stated that it agrees with the
intention of the proposed AD, but found the exceptions stated in
paragraphs (h)(4) through (6) of the proposed AD to be unclear. United
stated that it has other ongoing projects that use the instructions of
Boeing Service Bulletin 777-53-0084, Revision 2, dated December 9,
2020; Boeing Service Bulletin 777 53-0087, Revision 1, dated March 4,
2020; and Boeing Alert Requirements Bulletin 777-57A0122 RB, dated
October 8, 2021; to comply with the requirements of AD 2019-11-02,
Amendment 39-19648 (84 FR 28722, June 20, 2019) (AD 2019-11-02) and AD
2023-17-14, Amendment 39-22541 (88 FR 60111, August 31, 2023) (AD 2023-
17-14). United pointed out that ADs 2019-11-02 and 2023-17-14 have not
been updated to include the exceptions in those AD requirements and
recommends that the exceptions removed from paragraphs (h)(4) through
(6) of the proposed AD be added to the requirements of ADs 2019-11-02
and 2023-17-14.
The FAA disagrees with the request to remove the exceptions in
paragraphs (h)(4) through (6) of this AD. If cracking is found during
certain inspections required by Boeing Alert Requirements Bulletin 777-
53A0100 RB, dated March 16, 2023, then certain actions in Boeing
Service Bulletin 777-53-0084, Revision 2, dated December 9, 2020;
Boeing Service Bulletin 777-53-0087, Revision 1, dated March 4, 2020;
or Boeing Alert Requirements Bulletin 777-57A0122 RB, dated October 8,
2021; might be required as corrective actions. In order to address the
identified unsafe condition, the service information, as applicable,
must be accomplished with the exceptions specified in (h)(4) through
(6) of this AD. There are no new requirements for AD 2019-11-02 and AD
2023-17-14. However, as stated in paragraph (i) of this AD, for
airplanes on which a front spar lower chord modification specified in
Boeing Alert Requirements Bulletin 777-57A0122 RB is done as part of
the requirements of paragraphs (g) and (h)(6) of this AD, the
modification requirements of paragraph (g) of AD 2023-17-14 are
terminated for the applicable side (left or right) on which the
modification was done.
In addition, in the ``Approval'' paragraphs of Boeing Service
Bulletin 777-53-0084, Revision 2, dated December 9, 2020; Boeing
Service Bulletin 777-53-0087, Revision 1, dated March 4, 2020; and
Boeing Alert Requirements Bulletin 777-57A0122 RB, dated October 8,
2021; it specifies that certain actions are an alternative method of
compliance (AMOC) to the inspection and corrective action requirements
of paragraph (g) of AD 2019-11-02, for modified longerons only. The FAA
has not changed this AD in this regard.
Request To Add Paragraph for Terminating Action for AD 2019-11-02
American Airlines requested that the FAA add a paragraph similar to
paragraph (i) of the proposed AD for terminating action for AD 2023-17-
14 that refers to Boeing Service Bulletin 777-53-0087, Revision 1,
dated March 4, 2020, as the terminating action to AD 2019-11-02.
The FAA does not agree. As previously stated, the ``Approval''
paragraph of Boeing Service Bulletin 777-53-0087, Revision 1, dated
March 4, 2020, already includes an approval paragraph for the
requirements of AD 2019-11-02. The FAA has not revised this AD in this
regard.
Request To Add Clarifying Paragraph for Repetitive Inspections
American Airlines requested that the FAA add a paragraph clarifying
that ``If SB 777-53-0087 Rev 1 is accomplished due to findings from the
inspections described in SB 777-53A0081 R02 (AD 2019-11-02), and NO
skin repair is done, the repetitive inspections IAW SB 777-53A0100 will
still be required since terminating action for those inspections is
only valid if the underwing longeron AND fuselage skin modification is
accomplish in accordance with SB 777-53-0087 R01.''
The FAA concurs with American Airlines' statement that repetitive
inspections continue until the fuselage skin modification is done. The
UWL with fuselage skin modification is terminating action to the repeat
inspections in Boeing Alert Requirements Bulletin 777-53A0100 RB, dated
March 16, 2023. If Boeing Service Bulletin 777-53-0087, Revision 1,
dated March 4, 2020, is accomplished without the fuselage skin
modification, repeat inspections in accordance with Boeing Alert
Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, continue to
apply. The FAA notes that flagnote (a) in the tables in the
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 777-
53A0100 RB, dated March 16, 2023, specifies ``Accomplishment of the
left side UWL with fuselage skin modification in accordance with
Revision 1 of Boeing Service Bulletin 777-53-0087 is terminating action
for this repeat inspection.''
The FAA also notes where in the second paragraph of ``Other
Relevant Rulemaking'' of the NPRM states ``The accomplishment of the
longeron modification specified in Boeing Service Bulletin 777-53-0084,
Revision 2, dated December 9, 2020, or Boeing Service Bulletin 777-53-
0087, Revision 1, dated March 4, 2020'' the text should state ``The
accomplishment of the longeron modification with fuselage skin
modification specified in Boeing Service Bulletin 777-53-0084, Revision
2, dated December 9, 2020, or Boeing Service Bulletin 777-53-0087,
Revision 1, dated March 4, 2020.'' However, the ``Other Relevant
Rulemaking'' paragraphs are not restated in this AD. The FAA has not
revised this AD in this regard.
Request To Allow Later Revisions of Service Information
American Airlines requested that the FAA allow the use of future
revisions of Boeing Service Bulletin 777-53-0087, Revision 1, dated
March 4, 2020. American Airlines stated the Revision 2 of Boeing
Service Bulletin 777-53-0087 will add new replacement and supplemental
kits, add fastener installation instructions, update bracket
installation instructions, correct fastener callouts and correct
typographical errors.
The FAA does not agree. Revision 2 of Boeing Service Bulletin 777-
53-0087 has not yet been FAA approved nor been published. The FAA may
not refer to any document that does not yet exist in an AD. To allow
operators to use later
[[Page 81317]]
revisions of the referenced document (issued after publication of the
AD), either the FAA must revise the AD to reference specific later
revisions, or operators must request approval to use later revisions as
an alternative method of compliance with this AD under the provisions
of paragraph (j) of this AD.
Request To Clarify Paragraph (h)(5) of the Proposed AD
American Airlines requested that the FAA clarify if paragraph
(h)(5) of the proposed AD is exclusive to the center wing fuel tank
location, or whether adjustments should also be made to the other steps
that offer the choice to utilize Boeing Material Specification (BMS) 5-
95 sealant or other sealants.
The FAA agrees to clarify. The exception in paragraph (h)(5) of
this AD is applicable to sealant application in the center wing fuel
tank only. The use of BMS 5-95 sealant instead of BMS 5-45 sealant is
only a concern when the location being sealed is inside a fuel tank
such that the sealant is directly exposed to fuel. Only Figure 13 and
Figure 49 describe sealing operations inside a fuel tank using BMS 5-95
sealant. As such, paragraph (h)(5) of this AD is specifically limited
to flagnote (f) of Figure 13 and Figure 49. Other locations (i.e.,
other flagnotes and figures) in the service information that provide an
option of BMS 5-45 and BMS 5-95 are acceptable as written. The FAA also
notes that a similar rationale applies to the exception in paragraph
(h)(4) of this AD. The FAA has not changed this AD in this regard.
Conclusion
The FAA reviewed the relevant data, considered any comments
received, and determined that air safety requires adopting this AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products. Except for minor editorial changes, and
any other changes described previously, this AD is adopted as proposed
in the NPRM. None of the changes will increase the economic burden on
any operator.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed Boeing Alert Requirements Bulletin 777-53A0100 RB,
dated March 16, 2023. This material specifies procedures for external
or internal (depending on configuration) detailed and ultrasonic or
surface high frequency eddy current (HFEC) inspections for any cracking
of the left and right side fuselage skin common to the UWL, and
applicable on-condition actions. On-condition actions include, among
other things, modification of the fuselage skin, and post-modification
inspections and applicable corrective actions (repairs of cracking).
Compliance times for on-condition actions depend on inspection type,
inspection findings, and modification status.
The FAA also reviewed Boeing Multi Operator Message MOM-MOM-24-
0054-01B, dated January 26, 2024. This material specifies corrections
for Boeing Alert Requirements Bulletin 777-57A0122 RB, dated October 8,
2021, that address a non-destructive test manual (NDTM) error, fastener
callout errors, inadequate cap seal instructions, figure orientation
errors, minimum gap errors, missing fasteners on certain figures,
affected groups missing from certain figures, and typographical errors.
This material 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.
Costs of Compliance
The FAA estimates that this AD affects 272 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
----------------------------------------------------------------------------------------------------------------
External or internal inspections Up to 21 work-hours $0 $1,785 per $485,520 per
x $85 per hour = inspection cycle. inspection cycle.
$1,785 per
inspection cycle.
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The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of the
inspection. The agency has no way of determining the number of aircraft
that might need these actions:
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product
----------------------------------------------------------------------------------------------------------------
Modification............................ 420 work-hours x $85 per $40,620 $76,320.
hour = $35,700.
Post-modification inspections........... 46 work-hours x $85 per 0 $3,910 per inspection
hour = $3,910 per cycle.
inspection cycle.
----------------------------------------------------------------------------------------------------------------
The FAA has received no definitive data on which to base the cost
estimates for the on-condition repairs specified in this AD.
The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some or all of the costs of
this AD may be covered under warranty, thereby reducing the cost impact
on affected operators.
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.
[[Page 81318]]
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,
(2) Will not affect intrastate aviation in Alaska, and
(3) Will 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 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:
2024-16-09 The Boeing Company: Amendment 39-22815; Docket No. FAA-
2024-0769; Project Identifier AD-2023-00556-T.
(a) Effective Date
This airworthiness directive (AD) is effective November 12,
2024.
(b) Affected ADs
This AD affects AD 2023-17-14, Amendment 39-22541 (88 FR 60111,
August 31, 2023) (AD 2023-17-14).
(c) Applicability
This AD applies to The Boeing Company Model 777-200, -200LR, -
300, -300ER, and 777F series airplanes, certificated in any
category, as identified in Boeing Alert Requirements Bulletin 777-
53A0100 RB, dated March 16, 2023.
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by a report indicating multiple findings of
cracks in the fuselage skin common to the underwing longeron (UWL).
The FAA is issuing this AD to address fuselage skin cracking caused
by cold work surface upset that is not removed from the mating parts
and high joint load transfer or significant local bending stresses
at critical fastener locations. The unsafe condition, if not
addressed, could result in an inability of a principal structural
element (PSE) to sustain limit load, leading to reduced structural
integrity of the airplane and possible loss of control of the
airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Except as specified by paragraph (h) of this AD: At the
applicable times specified in the ``Compliance'' paragraph of Boeing
Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023, do
all applicable actions identified in, and in accordance with, the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
777-53A0100 RB, dated March 16, 2023.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
777-53A0100, dated March 16, 2023, which is referred to in Boeing
Alert Requirements Bulletin 777-53A0100 RB, dated March 16, 2023.
Note 2 to paragraph (g): Guidance for accomplishing certain on-
condition actions required by paragraph (g) of this AD can be found
in Boeing Service Bulletin 777-53-0084, Revision 2, dated December
9, 2020; Boeing Service Bulletin 777-53-0087 Revision 1, dated March
4, 2020; and Boeing Alert Requirements Bulletin 777-57A0122 RB,
dated October 8, 2021.
(h) Exceptions to Requirements Bulletin Specifications
(1) Where the Compliance Time columns of the tables in the
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 777-
53A0100 RB, dated March 16, 2023, use the phrase ``the original
issue date of Requirements Bulletin 777-53A0100 RB,'' this AD
requires using the effective date of this AD.
(2) Where Boeing Alert Requirements Bulletin 777-53A0100 RB,
dated March 16, 2023, and any service information referenced in
Boeing Alert Requirements Bulletin 777-53A0100 RB, dated March 16,
2023, specifies contacting Boeing for repair instructions: This AD
requires doing the repair using a method approved in accordance with
the procedures specified in paragraph (j) of this AD.
Note 3 to paragraph (h)(2): This note applies to paragraphs
(h)(2) and (3) of this AD. Boeing Alert Requirements Bulletin 777-
53A0100 RB, dated March 16, 2023, refers to Boeing Service Bulletin
777-53-0084, Revision 2, dated December 9, 2020; Boeing Service
Bulletin 777-53-0087, Revision 1, dated March 4, 2020; and Boeing
Alert Requirements Bulletin 777-57A0122 RB, dated October 8, 2021.
(3) Where any service information referenced in Boeing Alert
Requirements Bulletin 777-53A0100 RB, dated March 16, 2023,
specifies applying a cap seal (sealant) to a fastener, fastener
head, and fastener threads and collars inside the fuel tank, for
this AD, during application of any cap seal to a fastener, fastener
head, or fastener threads and collars inside the fuel tank, the cap
seal must be applied using a cap sealing procedure with thickness
greater than or equal to the dimensions given in Figure 1 to
paragraph (h)(3) of this AD.
Note 4 to paragraph (h)(3): Guidance on an acceptable cap
sealing procedure for accomplishing the actions required by
paragraph (h)(3) of this AD can be found in Boeing Model 777
Aircraft Maintenance Manual (AMM) section 28-11-00.
Figure 1 to Paragraph (h)(3)--Cap Sealing Dimensions (all Dimensions
are in Inches)
[[Page 81319]]
[GRAPHIC] [TIFF OMITTED] TR08OC24.009
(4) Where Boeing Alert Requirements Bulletin 777-53A0100 RB,
dated March 16, 2023, specifies doing actions ``in accordance with
Revision 2 of Boeing Service Bulletin 777-53-0084,'' for this AD,
where flagnote (f) of Figure 7 and Figure 22 of that referenced
service information (``Revision 2 of Boeing Service Bulletin 777-53-
0084'') includes a sealant callout of Boeing Material Specification
(BMS) 5-45 or an optional BMS 5-95, only BMS 5-45 is allowed.
(5) Where Boeing Alert Requirements Bulletin 777-53A0100 RB,
dated March 16, 2023, specifies doing actions ``in accordance with
Revision 1 of Boeing Service Bulletin 777-53-0087,'' for this AD,
where flagnote (f) of Figure 13 and Figure 49 of that referenced
service information (``Revision 1 of Boeing Service Bulletin 777-53-
0087'') includes a sealant callout of BMS 5-45 or an optional BMS 5-
95, only BMS 5-45 is allowed.
(6) Where Boeing Alert Requirements Bulletin 777-53A0100 RB,
dated March 16, 2023, specifies doing actions ``in accordance with
the original issue of Boeing Alert Requirements Bulletin 777-57A0122
RB,'' for this AD, the exceptions specified in paragraph (h)(6)(i)
through (v) of this AD apply to that referenced service information
(``the original issue of Boeing Alert Requirements Bulletin 777-
57A0122 RB'') and the corrections identified in Boeing Multi
Operator Message MOM-MOM-24-0054-01B, dated January 26, 2024, apply
to that referenced service information.
(i) Where the ``Compliance'' paragraph of the referenced service
information identifies ``Tables 1 through 50,'' the correct number
of tables is Tables 1 through 54.
(ii) The referenced service information does not specify the
application of cap seals to underwing longeron fasteners, fastener
heads, and fastener threads and collars for the airplane groups and
configurations identified in paragraphs (h)(6)(ii)(A) through (D) of
this AD. For those airplane groups and configurations, the
application of a cap seal to the underwing longeron fasteners at the
locations identified in Figures 81 and 144 is required during
installation of the underwing longeron and must be applied using a
cap sealing procedure with thickness greater than or equal to the
dimensions given in Figure 1 to paragraph (h)(3) of this AD.
(A) Groups 7 and 8, Configurations 5 through 8, on the left
side.
(B) Group 9, Configurations 1 and 2, on the left side.
(C) Groups 7 and 8, Configurations 2, 6, 10, and 14, on the
right side.
(D) Group 9, Configurations 1 and 3, on the right side.
(iii) For any inspection that may require the removal of
fastener cap seals, if the cap seal is removed, a cap seal of BMS 5-
45 sealant must be reapplied using a cap sealing procedure with a
thickness equal to or greater than the dimensions specified in
Figure 1 to paragraph (h)(3) of this AD before further flight after
completion of the inspection.
(iv) The referenced service information does not require the
restoration of any sealant removed to accomplish high frequency eddy
current and ultrasonic inspections external to the fuel tank in
Figures 1, 7, 11, and 17. Following completion of any inspection
required by those figures, replacement of the sealant described in
paragraph (h)(6)(iv)(A) and repair of the sealant described in
paragraph (h)(6)(iv)(B) of this AD, as applicable, is required.
(A) Where any sealant was removed from the heads of fasteners,
before further flight, cover and fillet seal the fasteners using BMS
5-45 or BMS 5-95 sealant.
Note 5 to paragraph (h)(6)(iv)(A): Guidance for accomplishing
the actions required by paragraph (h)(6)(iv)(A) of this AD can be
found in the Boeing Standard Overhaul Practices Manual (SOPM)
section 20-50-19.
(B) Following any sealant replacement required by paragraph
(h)(6)(iv)(A) of this AD, where any secondary fuel barrier coating
was removed, before further flight, repair the secondary fuel
barrier using BMS 5-81 sealant.
Note 6 to paragraph (h)(6)(iv)(B): Guidance for accomplishing
the actions required by paragraph (h)(6)(iv)(B) of this AD can be
found in Boeing Model 777 Aircraft Maintenance Manual (AMM) section
28-11-00.
(v) The Effectivity of the referenced service information does
not include Boeing Model 777F series airplanes having line numbers
1713, 1717, 1720, and 1724 through 1742 inclusive. For those
airplanes the applicable actions for Group 6 must be done.
(i) Terminating Action for AD 2023-17-14
For airplanes on which a front spar lower chord modification
specified in Boeing Alert Requirements Bulletin 777-57A0122 RB is
done as part of the requirements of paragraphs (g) and (h)(6) of
this AD, the modification requirements of paragraph (g) of AD 2023-
17-14 are terminated for the applicable side (left or right) on
which the modification was done.
(j) Alternative Methods of Compliance (AMOCs)
(1) The Manager, AIR-520, Continued Operational Safety 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 Continued Operational
Safety Branch, send it to the attention of the person identified in
paragraph (k)(1) of this AD. Information may be emailed to:
[email protected].
[[Page 81320]]
(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, AIR-
520, Continued Operational Safety 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
(1) For more information about this AD, contact Luis Cortez-
Muniz, Aviation Safety Engineer, FAA, 2200 South 216th St., Des
Moines, WA 98198; phone: 206-231-3958; email: [email protected].
(2) Material identified in this AD that is not incorporated by
reference is available at the address specified in paragraph (l)(3)
of this AD.
(l) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the material listed in this
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this material as applicable to do the actions
required by this AD, unless the AD specifies otherwise.
(i) Boeing Alert Requirements Bulletin 777-53A0100 RB, dated
March 16, 2023.
(ii) Boeing Multi Operator Message MOM-MOM-24-0054-01B, dated
January 26, 2024.
(3) For Boeing material, 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; website myboeingfleet.com.
(4) You may view this material 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 material at the National Archives and
Records Administration (NARA). For information on the availability
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].
Issued on August 1, 2024.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft
Certification Service.
[FR Doc. 2024-23117 Filed 10-7-24; 8:45 am]
BILLING CODE 4910-13-P