[Federal Register Volume 88, Number 67 (Friday, April 7, 2023)]
[Rules and Regulations]
[Pages 20732-20735]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-07090]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0889; Project Identifier AD-2021-00614-T; 
Amendment 39-22373; AD 2023-05-04]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This AD 
was prompted by reports of ram air turbine (RAT) pump barrel assembly 
failures, which caused the RAT to fail to provide hydraulic power. The 
failures were determined to be caused by variations in the bronze metal 
used during manufacturing, which can result in varying fatigue 
properties. This AD requires an inspection or records review to 
determine the part number of the RAT pump and control module (PCM) and 
of the RAT assembly, and replacement of any RAT PCM or any RAT assembly 
having certain part numbers. 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 May 12, 2023.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of May 12, 
2023.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2022-0889; 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 Blvd., 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 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-2022-0889.

FOR FURTHER INFORMATION CONTACT: Douglas Tsuji, Senior Aerospace 
Engineer, Systems and Equipment Section, FAA, Seattle ACO Branch, 2200 
South 216th St, Des Moines, WA 98198; phone: 206-231-3548; 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 all The Boeing Company 
Model 787-8, 787-9, and 787-10 airplanes. The NPRM published in the 
Federal Register on September 21, 2022 (87 FR 57653). The NPRM was 
prompted by reports of RAT pump barrel assembly failures, which caused 
the RAT to fail to provide hydraulic power. The failures were 
determined to be caused by variations in the bronze metal used during 
manufacturing, which can result in varying fatigue properties. In the 
NPRM, the FAA proposed to require an inspection or records review to 
determine the part number of the RAT PCM and of the RAT assembly, and 
replacement of any RAT PCM or any RAT assembly having certain part 
numbers. In the NPRM, the FAA also proposed to prohibit the 
installation of affected parts. The FAA is issuing this AD to address 
fatigue or cracking of the RAT hydraulic pump bronze cylinder block. 
This condition, if not addressed, could cause failure of the RAT pump 
and subsequent loss of backup hydraulic power for the flight controls, 
which can result in loss of continued safe flight and landing.

[[Page 20733]]

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from the Air Line Pilots Association, 
International (ALPA) who supported the NPRM without change.
    The FAA received additional comments from United Airlines (UAL), 
who supported the NPRM and also had additional comments, and from 
Boeing. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Request To Revise a RAT Assembly Part Number

    Boeing requested that paragraphs (j)(1) and (2) of the proposed AD 
be revised to specify RAT assembly part number (P/N) 7000011H08, 
instead of P/N 700011H08.
    The FAA agrees with the commenter's request to fix this 
typographical error and has revised paragraphs (j)(1) and (2) of this 
AD accordingly.

Request To Revise the Applicability

    Boeing requested that the proposed AD be revised to specify that it 
applies only to the airplanes identified in Boeing Alert Requirements 
Bulletin B787-81205-SB290039-00 RB, Issue 002, dated October 26, 2021, 
instead of all Model 787-8, 787-9, and 787-10 airplanes. Boeing claimed 
that Model 787 airplanes delivered after the incorporation of CN-
AA82746B were configured with the current version of the RAT assembly 
and PCM. Boeing added that, by design and process, there are no 
alternative installation configurations permitted either in production 
or in service.
    The FAA disagrees with the commenter's request. As stated in the 
NPRM, the FAA considers the RAT PCMs and RAT assemblies to be rotable 
parts, and has determined that these parts could later be installed on 
airplanes that were initially delivered with acceptable RAT PCMs and 
RAT assemblies, thereby subjecting those airplanes to the unsafe 
condition. The FAA acknowledges there is a low possibility that 
airplanes delivered with the latest parts have had those parts 
replaced, but the possibility does exist. The FAA has not changed this 
AD regarding this issue.

Request To Clarify Related AD

    UAL requested clarification of how the requirements of AD 2016-07-
25, Amendment 39-18470 (71 FR 21720, April 13, 2016) (AD 2016-07-25) 
impact the requirements of the proposed AD. UAL noted that Boeing Alert 
Requirements Bulletin B787-81205-SB290039-00 RB, Issue 002, dated 
October 26, 2021, provides an alternative method of compliance (AMOC) 
for AD 2016-07-25 to incorporate Boeing Alert Requirements Bulletin 
B787-81205-SB290039-00 RB, Issue 002, dated October 26, 2021, on 
aircraft in the applicability of AD 2016-07-05.
    The FAA agrees to clarify. AD 2016-07-25 will not affect this AD. 
AD 2016-07-25 requires changes to the RAT assembly's volume fuse to 
address potential failure of the RAT pump at low speeds. AD 2016-07-25 
requires installation of a new RAT assembly, P/N 7000011H08, with a 
compliance time of within 36 months after May 18, 2016. This AD 
requires replacing any RAT assembly having P/N 7000011H08 with P/N 
7000011H09. The RAT assembly P/N 7000011H09 incorporates the previous 
volume fuse changes and the new pump barrel changes. The AMOC to AD 
2016-07-25 associated with Boeing Alert Requirements Bulletin B787-
81205-SB290039-00 RB Issue 002, dated October 26 2021, essentially 
allows installation of the RAT assembly having P/N 7000011H09 in lieu 
of P/N 7000011H08. The FAA has not changed this AD regarding this 
issue.

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.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin B787-81205-
SB290039-00 RB, Issue 002, dated October 26, 2021. This service 
information specifies procedures for replacing any RAT PCM having part 
number (P/N) 7001267H06 with P/N 7001267H07, and replacing any RAT 
assembly having P/N 7000011H08 with P/N 7000011H09. 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 148 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Inspection or records review........  1 work-hour x $85 per                $0              $85          $12,580
                                       hour = $85.
----------------------------------------------------------------------------------------------------------------


                                      Estimated Costs for Optional Actions
----------------------------------------------------------------------------------------------------------------
                Action                        Labor cost               Parts cost            Cost per product
----------------------------------------------------------------------------------------------------------------
Replace RAT PCM......................  5 work-hours x $85 per   Up to $95,210..........  Up to $95,635.
                                        hour = $425.
Replace RAT assembly.................  5 work-hours x $85 per   Up to $680,912.........  Up to $681,337.
                                        hour = $425.
----------------------------------------------------------------------------------------------------------------

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

[[Page 20734]]

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 adding the following new airworthiness 
directive:

2023-05-04 The Boeing Company: Amendment 39-22373; Docket No. FAA-
2022-0889; Project Identifier AD-2021-00614-T.

(a) Effective Date

    This airworthiness directive (AD) is effective May 12, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 787-8, 787-9, 
and 787-10 airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 29, Hydraulic 
power.

(e) Unsafe Condition

    This AD was prompted by reports of ram air turbine (RAT) 
assembly failures, which caused the RAT to fail to provide hydraulic 
power. The failures were determined to be caused by variations in 
the bronze metal used during manufacturing, which can result in 
varying fatigue properties. The FAA is issuing this AD to address 
fatigue or cracking of the RAT hydraulic pump bronze cylinder block. 
This condition, if not addressed, could cause failure of the RAT 
pump and subsequent loss of backup hydraulic power for the flight 
controls, which can result in loss of continued safe flight and 
landing.

(f) Compliance

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

(g) Inspection

    For airplanes with an original airworthiness certificate or 
original export certificate of airworthiness issued on or before the 
effective date of this AD: Within 60 months after the effective date 
of this AD, inspect the RAT pump and control module (PCM) and the 
RAT assembly to determine the part number. A review of airplane 
maintenance records is acceptable in lieu of this inspection if the 
RAT PCM and the RAT assembly part numbers can be conclusively 
determined from that review.

(h) Replacements

    If, during the inspection required by paragraph (g), any RAT PCM 
having part number (P/N) 7001267H06 or any RAT assembly having P/N 
7000011H08 is found: Except as specified by paragraph (i) of this 
AD, at the applicable times specified in the ``Compliance'' 
paragraph of Boeing Alert Requirements Bulletin B787-81205-SB290039-
00 RB, Issue 002, dated October 26, 2021, do all applicable actions 
identified in, and in accordance with, the Accomplishment 
Instructions of Boeing Alert Requirements Bulletin B787-81205-
SB290039-00 RB, Issue 002, dated October 26, 2021.
    Note 1 to paragraph (h): Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
B787-81205-SB290039-00, Issue 002, dated October 26, 2021, which is 
referred to in Boeing Alert Requirements Bulletin B787-81205-
SB290039-00 RB, Issue 002, dated October 26, 2021.

(i) Exception to Service Information Specifications

    Where Boeing Alert Requirements Bulletin B787-81205-SB290039-00 
RB, Issue 002, dated October 26, 2021, uses the phrase ``the Issue 
001 date of Requirements Bulletin B787-81205-SB290039-00 RB,'' this 
AD requires using ``the effective date of this AD.''

(j) 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: Installation of a RAT PCM, part number 
(P/N) 7001267H06, or RAT assembly, P/N 7000011H08, is prohibited as 
of the effective date of this AD.
    (2) For airplanes with an original airworthiness certificate or 
original export certificate of airworthiness issued on or before the 
effective date of this AD, installation of a RAT PCM, P/N 
7001267H06, or RAT assembly, P/N 7000011H08, is allowed until the 
actions required by paragraph (h) of this AD are accomplished.

(k) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (h) of this AD, if those actions were performed before the 
effective date of this AD using Boeing Alert Requirements Bulletin 
B787-81205-SB290039-00 RB, Issue 001, dated November 3, 2020.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or responsible Flight Standards Office, 
as appropriate. If sending information directly to the manager of 
the certification office, send it to the attention of the person 
identified in paragraph (m)(1) 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, 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.

(m) Additional Information

    (1) For more information about this AD, contact Douglas Tsuji, 
Senior Aerospace Engineer, Systems and Equipment Section, FAA, 
Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; 
phone: 206-231-3548; email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (n)(3) and (4) of this AD.

(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.

[[Page 20735]]

    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Requirements Bulletin B787-81205-SB290039-00 
RB, Issue 002, dated October 26, 2021.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; website myboeingfleet.com.
    (4) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, [email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on March 5, 2023.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2023-07090 Filed 4-6-23; 8:45 am]
BILLING CODE 4910-13-P


