[Federal Register Volume 89, Number 22 (Thursday, February 1, 2024)]
[Rules and Regulations]
[Pages 6425-6428]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-01969]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1037; Project Identifier AD-2023-00511-T; 
Amendment 39-22655; AD 2024-01-04]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2020-26-
08, which applied to The Boeing Company Model 787-8, 787-9, and 787-10 
airplanes powered by Rolls-Royce Trent 1000 engines. AD 2020-26-08 
required repetitive inspections of the inner fixed structure (IFS) 
forward upper fire seal and thermal insulation blankets in the forward 
upper area of the thrust reverser (TR) for damage and applicable on-
condition actions. Since the FAA issued AD 2020-26-08, the FAA 
determined that a new upper splitter fairing assembly is needed to 
prevent damage to the fire seal and thermal insulation blanket. This AD 
continues to require the actions specified in AD 2020-26-08 and 
requires determining if an affected part number of the upper splitter 
fairing assembly is installed on the engine, replacing an affected 
upper splitter fairing assembly part number with a new upper splitter 
fairing assembly part number, inspecting the IFS forward upper fire 
seal and thermal insulation blanket for any damage, and applicable on-
condition actions. This AD also prohibits the installation of affected 
parts. The FAA is issuing this AD to address the unsafe condition on 
these products.

DATES: This AD is effective March 7, 2024.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of March 7, 
2024.
    The Director of the Federal Register approved the incorporation by 
reference of a certain other publication listed in this AD as of 
January 27, 2021 (85 FR 83755, December 23, 2020).

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-1037; 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 service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Boulevard, MC 110-SK57, Seal Beach, 
CA 90740-5600; telephone 562-797-1717; website myboeingfleet.com.
     You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 South 
216th Street, 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-2023-1037.

FOR FURTHER INFORMATION CONTACT: Tak Kobayashi, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; telephone 
206-231-3553; email [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2020-26-08, Amendment 39-21363 (85 FR 
83755, December 23, 2020) (AD 2020-26-08). AD 2020-26-08 applied to The 
Boeing Company Model 787-8, 787-9, and 787-10 airplanes powered by 
Rolls-Royce Trent 1000 engines. AD 2020-26-08 required repetitive 
inspections of the IFS forward upper fire seal and thermal insulation 
blankets in the forward upper area of the TR for damage and applicable 
on-condition actions.
    The NPRM published in the Federal Register on May 25, 2023 (88 FR 
33851). The NPRM was prompted by a

[[Page 6426]]

determination that a new upper splitter fairing assembly part number 
(P/N) KH99185 should be required to prevent damage to the fire seal and 
thermal insulation blanket. In the NPRM, the FAA proposed to continue 
to require the actions specified in AD 2020-26-08 and require 
determining if upper splitter fairing assembly P/N KH60375 is installed 
on the engine, replacing upper splitter fairing assembly P/N KH60375 
with a new upper splitter fairing assembly part number, inspecting the 
IFS forward upper fire seal and thermal insulation blanket for any 
damage, and applicable on-condition actions.
    The FAA issued a supplemental NPRM (SNPRM) to amend 14 CFR part 39 
to supersede AD 2020-26-08. The SNPRM published in the Federal Register 
on October 31, 2023 (88 FR 74372). The SNPRM was prompted by the FAA 
identifying an additional affected upper splitter fairing assembly, P/N 
KH11560, that must be replaced to address the unsafe condition. In the 
SNPRM, the FAA revised the NPRM by proposing replacement of the 
additional upper splitter fairing assembly. The FAA is issuing this AD 
to address the damage to the IFS forward upper fire seal and the 
thermal insulation blankets of the TR due to airflow through structural 
gapping that could occur at the interface between the leading edge of 
the IFS and the engine splitter structure during flight. Failure of the 
IFS forward upper fire seal could cause the loss of seal pressurization 
and degrade the ability to detect and extinguish an engine fire, 
resulting in an uncontrolled fire. Damage to the TR insulation blanket 
could result in thermal damage to the TR inner wall, the subsequent 
release of engine exhaust components, and consequent damage to critical 
areas of the airplane. Furthermore, damage to the TR inner wall and IFS 
forward upper fire seal could compromise the integrity of the firewall 
and its ability to contain an engine fire, resulting in an uncontrolled 
fire.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from The Air Line Pilots Association, 
International and The Boeing Company, who both supported the SNPRM 
without change.

Conclusion

    The FAA reviewed the relevant data, considered the 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. This AD is adopted as proposed in the 
SNPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-
SB720007-00 RB, Issue 001, dated December 12, 2022. This service 
information specifies replacing the upper splitter fairing assembly 
with a new upper splitter fairing assembly with ramp fairing 
incorporated and doing a general visual inspection of the IFS forward 
upper fire seal and thermal insulation blanket of the left and right TR 
halves for any damage. This service information also specifies 
applicable on-condition actions, including replacing the IFS forward 
upper fire seal and thermal insulation blanket of each TR half if 
damage is found. The procedures in the service information apply to 
each affected engine.
    The FAA also reviewed Boeing Alert Requirements Bulletin B787-
81205-SB780041-00 RB, Issue 002, dated December 21, 2021. This service 
information contains procedures for repetitive inspections of the IFS 
forward upper fire seal and thermal insulation blanket of the left and 
right TR halves for any damage. This service information also specifies 
applicable on-condition actions, including replacing the IFS forward 
upper fire seal and thermal insulation blanket of each TR half if 
damage is found. The procedures in the service information apply to 
each affected engine.
    This AD also requires Boeing Alert Requirements Bulletin B787-
81205-SB780041-00 RB, Issue 001, dated March 31, 2020, which the 
Director of the Federal Register approved for incorporation by 
reference as of January 27, 2021 (85 FR 83755, December 23, 2020).
    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 ADDRESSES.

Costs of Compliance

    The FAA estimates that this AD affects 13 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                   Parts
            Action                Labor cost        cost         Cost per product        Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Inspection (retained actions   2 work-hours x           $0  $170 per inspection cycle  $2,210 per inspection
 from AD 2020-26-08).           $85 per hour =                                          cycle.
                                $170 per
                                inspection
                                cycle.
Inspection or records review   1 work-hour x             0  $85......................  $1,105.
 (new action).                  $85 per hour =
                                $85.
Replacement of each upper      71 work-hours x     230,000  $236,035.................  $3,068,455.
 splitter fairing assembly      $85 per hour =
 (new action).                  $6,035.
Inspection (new action)......  2 work-hours x            0  $170.....................  $2,210.
                                $85 per hour =
                                $170.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements 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 replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
            Action                  Labor cost             Parts cost                  Cost per product
----------------------------------------------------------------------------------------------------------------
Fire seal replacement.........  2 work-hours x     $1,383 per TR half.......  $1,553 per TR half (4 TR halves
                                 $85 per hour =                                per airplane).
                                 $170 per TR half.
Thermal insulation blanket      1 work-hour x $85  $18,214 per TR half......  $18,299 per TR half.
 replacement.                    per hour = $85
                                 per TR half.
----------------------------------------------------------------------------------------------------------------


[[Page 6427]]

    According to the manufacturer, some of the costs of this AD may be 
covered under warranty by Goodrich, thereby reducing the cost impact on 
affected operators. The FAA does not control warranty coverage for 
affected operators. As a result, the FAA has included all known costs 
in the cost estimate.

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,
    (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:
0
a. Removing Airworthiness Directive 2020-26-08, Amendment 39-21363 (85 
FR 83755, December 23, 2020); and
0
b. Adding the following new Airworthiness Directive:

2024-01-04 The Boeing Company: Amendment 39-22655; Docket No. FAA-
2023-1037; Project Identifier AD-2023-00511-T.

(a) Effective Date

    This airworthiness directive (AD) is effective March 7, 2024.

(b) Affected ADs

    This AD replaces AD 2020-26-08, Amendment 39-21363 (85 FR 83755, 
December 23, 2020) (AD 2020-26-08).

(c) Applicability

    This AD applies to The Boeing Company Model 787-8, 787-9, and 
787-10 airplanes, certificated in any category, with Rolls-Royce 
Trent 1000 engines installed.

(d) Subject

    Air Transport Association (ATA) of America Code 72, Turbine/
turboprop engine.

(e) Unsafe Condition

    This AD was prompted by reports of Rolls-Royce Trent 1000 
powered airplanes having damage to the thrust reverser inner fixed 
structure (IFS) forward upper fire seal and damage to thermal 
insulation blankets in the forward upper area of the thrust reverser 
(TR). The FAA is issuing this AD to address the damage to the IFS 
forward upper fire seal and the thermal insulation blankets of the 
TR due to airflow through structural gapping that could occur at the 
interface between the leading edge of the IFS and the engine 
splitter structure during flight. Failure of the IFS forward upper 
fire seal could cause the loss of seal pressurization and degrade 
the ability to detect and extinguish an engine fire, resulting in an 
uncontrolled fire. Damage to the TR insulation blanket could result 
in thermal damage to the TR inner wall, the subsequent release of 
engine exhaust components, and consequent damage to critical areas 
of the airplane. Furthermore, damage to the TR inner wall and IFS 
forward upper fire seal could compromise the integrity of the 
firewall and its ability to contain an engine fire, resulting in an 
uncontrolled fire.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Retained Actions, With Additional Service Information, Revised 
Affected Airplanes, and New Terminating Action

    This paragraph restates the requirements of paragraph (g) of AD 
2020-26-08, with additional service information, revised affected 
airplanes, and new terminating action. For airplanes with an 
original airworthiness certificate or original export certificate of 
airworthiness issued on or before the effective date of this AD and 
for airplanes listed in the ``Effectivity'' section of Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022: Except as specified by paragraph (h) of this AD, 
at the applicable times specified in the ``Compliance'' paragraph of 
Boeing Alert Requirements Bulletin B787-81205-SB780041-00 RB, Issue 
001, dated March 31, 2020, or Boeing Alert Requirements Bulletin 
B787-81205-SB780041-00 RB, Issue 002, dated December 21, 2021, do 
all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
B787-81205-SB780041-00 RB, Issue 001, dated March 31, 2020, or 
Boeing Alert Requirements Bulletin B787-81205-SB780041-00 RB, Issue 
002, dated December 21, 2021. Accomplishing the actions required by 
paragraph (i)(2) of this AD terminates the actions required by this 
paragraph.

    Note 1 to paragraph (g): Guidance for accomplishing the actions 
required by paragraph (g) of this AD can be found in Boeing Alert 
Service Bulletin B787-81205-SB780041-00, Issue 001, dated March 31, 
2020, which is referred to in Boeing Alert Requirements Bulletin 
B787-81205-SB780041-00 RB, Issue 001, dated March 31, 2020; or in 
Boeing Alert Service Bulletin B787-81205-SB780041-00, Issue 002, 
dated December 21, 2021, which is referred to in Boeing Alert 
Requirements Bulletin B787-81205-SB780041-00 RB, Issue 002, dated 
December 21, 2021.

(h) Retained Exceptions to Service Information Specifications for 
Paragraph (g) of This AD, With Additional Service Information

    This paragraph restates the exceptions specified in paragraph 
(h) of AD 2020-26-08, with additional service information. Where 
Boeing Alert Requirements Bulletin B787-81205-SB780041-00 RB, Issue 
001, dated March 31, 2020, or Boeing Alert Requirements Bulletin 
B787-81205-SB780041-00 RB, Issue 002, dated December 21, 2021, uses 
the phrase ``the Issue 001 date of Requirements Bulletin B787-81205-
SB780041-00 RB,'' this AD requires using January 27, 2021, (the 
effective date of AD 2020-26-08).

(i) New Required Actions

    (1) For airplanes with original airworthiness certificate or 
original export certificate of airworthiness issued on or before the 
effective date of this AD and for airplanes listed in the 
``Effectivity'' section of Boeing Alert Requirements Bulletin B787-
81205-SB720007-00 RB, Issue 001, dated December 12, 2022: Within 7 
years after the effective date of this AD, or within 7 years

[[Page 6428]]

after the date of issuance of the original airworthiness certificate 
or original export certificate of airworthiness, whichever occurs 
later, inspect the airplane to determine the part number of the 
upper splitter fairing assembly installed on each engine. A review 
of airplane maintenance records is acceptable in lieu of this 
inspection if the part number of the upper splitter fairing assembly 
can be conclusively determined from that review. For engines on 
which no upper splitter fairing assembly part number (P/N) KH60375 
or P/N KH11560 is installed, the actions required by paragraph (g) 
of this AD are no longer required for that engine.
    (2) If, during any inspection or records review required by 
paragraph (i)(1) of this AD, an upper splitter fairing assembly P/N 
KH60375 or P/N KH11560 is found on any engine of an airplane: Except 
as specified by paragraph (j) of this AD, at the applicable times 
specified in the ``Compliance'' paragraph of Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022, do all applicable actions identified in, and in 
accordance with, the Accomplishment Instructions of Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022, for each affected engine. Accomplishing the 
actions required by this paragraph on all affected engines of an 
airplane terminates the actions required by paragraph (g) of this AD 
for that airplane.

    Note 2 to paragraph (i)(2):  Guidance for accomplishing the 
actions required by paragraph (i)(2) of this AD can be found in 
Boeing Alert Service Bulletin B787-81205-SB720007-00, Issue 001, 
dated December 12, 2022, which is referred to in Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022.

(j) Exceptions to Service Information Specifications for Paragraph 
(i)(2) of This AD

    (1) Where the Compliance Time column of table 5 in the 
``Compliance'' paragraph of Boeing Alert Requirements Bulletin B787-
81205-SB720007-00 RB, Issue 001, dated December 12, 2022, uses the 
phrase ``the Issue 001 date of Requirements Bulletin B787-81205-
SB720007-00 RB,'' this AD requires using ``the effective date of 
this AD.''
    (2) Where the service information referenced in Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022, specifies to remove the existing upper splitter 
fairing assembly P/N KH60375, this AD requires removing the existing 
upper splitter fairing assembly P/N KH60375 or P/N KH11560.

(k) Parts Installation Prohibition

    (1) For airplanes with an original airworthiness certificate or 
original export certificate of airworthiness issued after the 
effective date of this AD, except for airplanes listed in Boeing 
Alert Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, 
dated December 12, 2022: As of the effective date of this AD, no 
person may install an engine with an upper splitter fairing assembly 
P/N KH60375 or P/N KH11560 on any airplane.
    (2) For airplanes with original airworthiness certificate or 
original export certificate of airworthiness issued on or before the 
effective date of this AD and for airplanes listed in Boeing Alert 
Requirements Bulletin B787-81205-SB720007-00 RB, Issue 001, dated 
December 12, 2022, on which, during the actions required by 
paragraph (i)(1) of this AD, no upper splitter fairing assembly P/N 
KH60375 or P/N KH11560 was installed on both engines: After 
accomplishing the inspection or records review required by paragraph 
(i)(1) of this AD, no person may install an engine with an upper 
splitter fairing assembly P/N KH60375 or P/N KH11560 for replacement 
of an engine on those airplanes.

(l) 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 AIR-520, Continued 
Operational Safety Branch, send it to the attention of the person 
identified in paragraph (m) of this AD. Information may be emailed 
to [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by The Boeing Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, AIR-
520, Continued Operational Safety Branch, 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.

(m) Related Information

    For more information about this AD, contact Tak Kobayashi, 
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, 
WA 98198; telephone 206-231-3553; email [email protected].

(n) 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 this AD specifies otherwise.
    (3) The following service information was approved for IBR on 
March 7, 2024.
    (i) Boeing Alert Requirements Bulletin B787-81205-SB720007-00 
RB, Issue 001, dated December 12, 2022.
    (ii) Boeing Alert Requirements Bulletin B787-81205-SB780041-00 
RB, Issue 002, dated December 21, 2021.
    (4) The following service information was approved for IBR on 
January 27, 2021 (85 FR 83755, December 23, 2020).
    (i) Boeing Alert Requirements Bulletin B787-81205-SB780041-00 
RB, Issue 001, dated March 31, 2020.
    (ii) [Reserved]
    (5) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Boulevard, MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; website myboeingfleet.com.
    (6) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th Street, Des Moines, WA. For information on the 
availability of this material at the FAA, call 206-231-3195.
    (7) 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 January 6, 2024.
Caitlin Locke,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2024-01969 Filed 1-31-24; 8:45 am]
BILLING CODE 4910-13-P