preamble attached >>>
ADs updated daily at www.Tdata.com
2024-18-03 BOMBARDIER, INC.: Amendment 39-22837; Docket No. FAA-2024-1003; Project Identifier MCAI-2023-00712-T.
(a) EFFECTIVE DATE

    This airworthiness directive (AD) is effective November 12, 2024.

(b) AFFECTED ADS

    This AD replaces AD 2023-11-01, Amendment 39-22446 (88 FR 44042,  July
    11, 2023) (AD 2023-11-01).

(c) APPLICABILITY

    This AD applies to all Bombardier, Inc., Model BD-100-1A10  airplanes,
    certificated in any category.

(d) SUBJECT

    Air Transport Association (ATA) of America Code 24, Electrical  Power.

(e) UNSAFE CONDITION

    This AD was prompted by multiple reports of erratic electrical  system
    status  on  the  push  button  annunciators  (PBAs)  and  the   engine
    instrument and crew alerting system (EICAS) while on-ground and during
    flight, and  by the  determination that  certain direct  current power
    center (DCPC)  units require  additional modification  or replacement.
    The FAA is issuing this AD to address erratic indications, which could
    cause the flightcrew  to turn off  fully operational electrical  power
    sources, leading to partial or complete loss of electrical power.  The
    unsafe condition,  if not  addressed, could  result in  loss of flight
    displays and reduced controllability of the airplane.

(f) COMPLIANCE

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

(g) RECORDS CHECK

    For any left-hand (LH) DCPC unit having part number (P/N)  975GC02Y04,
    975GC02Y05, 975GC02Y06, or 975GC02Y07 that was not cleaned before  the
    effective date  of this  AD as  specified in  Safran Service  Bulletin
    975GC02Y-24-018 or replaced  before the effective  date of this  AD as
    specified  in Bombardier  Service Bulletin  100-24- 29  or  Bombardier
    Service Bulletin 350-24-004: Within  60 days after the  effective date
    of this AD, verify  the total flight hours  of the LH DCPC  unit since
    the date of  manufacture by doing  a records check  in accordance with
    paragraph 2.B.(1) of the Accomplishment Instructions of the applicable
    service bulletin identified in paragraphs (g)(1) and (2) of this AD.

(1) For airplanes having serial numbers 20001 through 20500 inclusive, use
    Bombardier  Service  Bulletin  100-24-29,  dated  April  9,  2021;  or
    Revision 01, dated July 27, 2023. As of the effective date of this AD,
    use only  Bombardier Service  Bulletin 100-24-29,  Revision 01,  dated
    July 27, 2023.

(2) For airplanes having serial numbers 20501 through 20999 inclusive, use
    Bombardier  Service  Bulletin  350-24-004,  dated  April  9,  2021; or
    Revision 01, dated July 27, 2023. As of the effective date of this AD,
    use only  Bombardier Service  Bulletin 350-24-004,  Revision 01, dated
    July 27, 2023.

(h) REPLACEMENT OF THE LH DCPC

    If, during the records check required by paragraph (g) of this AD, the
    total flight hours since  date of manufacture of  the LH DCPC unit  is
    equal to or  more than 3,500  total flight hours  as of the  effective
    date  of  this AD,  and  the LH  DCPC  was not  previously  cleaned as
    specified in Safran Service  Bulletin 957GC02Y-24-018, or replaced  as
    specified  in  Bombardier  Service  Bulletin  100-24-29  or Bombardier
    Service Bulletin 350-24-004: Within 12 months after the effective date
    of this AD, remove, replace with LH DCPC P/N 975GC02Y08, test the DCPC
    logic and protection cards, and do the functional test for the LH DCPC
    unit, in accordance with the applicable service information  specified
    in paragraphs (h)(1)  through (8) of  this AD. If  any test fails,  do
    corrective actions, and  repeat the test  before further flight  until
    the test passes.

(1) Task 24-61-01-000-801 Removal of  the DC Power Center (DCPC),  Subject
    24-61-01  DC  Power Center  (DCPC)--Removal/Installation,  Chapter 24-
    -Electrical  Power,  Bombardier  Challenger  300  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 300  AMM, Revision  82, dated
    November 9, 2023.

(2) Task 24-61-01-000-801 Removal of  the  DC Power Center (DCPC), Subject
    24-61-01  DC  Power Center  (DCPC)--Removal/Installation,  Chapter 24-
    -Electrical  Power,  Bombardier  Challenger  350  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 350  AMM, Revision  38, dated
    November 9, 2023.

(3) Task  24-61-01-400-801  Installation of  the DC  Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Removal/Installation, Chapter
    24 --Electrical Power, Bombardier Challenger 300 Aircraft  Maintenance
    Manual,  Part Two,  Publication  No.  CH 300  AMM, Revision  82, dated
    November 9, 2023.

(4) Task  24-61-01-400-801  Installation of  the DC  Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Removal/Installation, Chapter
    24 --Electrical Power, Bombardier Challenger 350 Aircraft  Maintenance
    Manual,  Part Two,  Publication  No.  CH 350  AMM, Revision  38, dated
    November 9, 2023.

(5) For airplanes having serial number 20001 through 20500 inclusive,  use
    paragraph  2.D.  of  the  Accomplishment  Instructions  of  Bombardier
    Service Bulletin 100-24-30, dated November 29, 2022.

(6) For airplanes having serial number 20501 through 20999 inclusive,  use
    paragraph  2.D.  of  the  Accomplishment  Instructions  of  Bombardier
    Service Bulletin 350-24-005, dated November 29, 2022.

(7) Task 24-61-01-720-801 Functional Test  of the DC Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Adjustment/Test, Chapter  24-
    -Electrical  Power,  Bombardier  Challenger  300  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 300  AMM, Revision  82, dated
    November 9, 2023.

(8) Task 24-61-01-720-801 Functional Test  of the DC Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Adjustment/Test, Chapter  24-
    -Electrical  Power,  Bombardier  Challenger  350  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 350  AMM, Revision  38, dated
    November 9, 2023.

(i) EXCEPTION TO THE SERVICE INFORMATION

    Although  the  note  in   paragraph  2.B.(4)  of  the   Accomplishment
    Instructions of Bombardier Service Bulletin 100-24-29, dated April  9,
    2021, and  Revision 01,  dated July  27, 2023;  and Bombardier Service
    Bulletin 350-24-004, dated April 9, 2021, and Revision 01, dated  July
    27, 2023,  specify that  actions will  reset "the  unit total  flight
    hours to  zero at  date of  incorporation," this  AD does not include
    that requirement.

(j) MODIFICATION

    For  LH  DCPC  P/N  975GC02Y07  units  that  were  cleaned  before the
    effective date  of this  AD as  specified in  Safran Service  Bulletin
    975GC02Y-24-018, or replaced before the  effective date of this AD  as
    specified  in  Bombardier  Service  Bulletin  100-24-29  or Bombardier
    Service Bulletin 350-24-004: Within 12 months after the effective date
    of  this AD,  modify each  LH DCPC  P/N 975GC02Y07  into LH  DCPC  P/N
    975GC02Y08, in  accordance with  paragraph 2.C.  of the Accomplishment
    Instructions  of  the   applicable  service  bulletin   identified  in
    paragraph (j)(1) or  (2) of this  AD. Before further  flight after the
    modification, test the DCPC  logic and protection cards  in accordance
    with  paragraph  2.D.  of  the  Accomplishment  Instructions  of   the
    applicable service bulletin identified  in paragraph (j)(1) or  (2) of
    this  AD,  and  do  the  functional test  for  the  LH  DCPC  unit, in
    accordance  with  the  applicable  service  information  specified  in
    paragraph (j)(3) or (4) of this  AD. If any test fails, do  corrective
    actions, and  repeat the  test before  further flight  until the  test
    passes.

(1) For airplanes having serial number 20001 through 20500 inclusive,  use
    Bombardier Service Bulletin 100-24-30, dated November 29, 2022.

(2) For airplanes having serial number 20501 through 20999 inclusive,  use
    Bombardier Service Bulletin 350-24-005, dated November 29, 2022.

(3) Task 24-61-01-720-801 Functional Test  of the DC Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Adjustment/Test, Chapter  24-
    -Electrical  Power,  Bombardier  Challenger  300  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 300  AMM, Revision  82, dated
    November 9, 2023.

(4) Task 24-61-01-720-801 Functional Test  of the DC Power Center  (DCPC),
    Subject 24-61-01 DC Power Center (DCPC)--Adjustment/Test, Chapter  24-
    -Electrical  Power,  Bombardier  Challenger  350  Aircraft Maintenance
    Manual,  Part Two,  Publication  No.  CH 350  AMM, Revision  38, dated
    November 9, 2023.

(k) REPLACEMENT  OF  CERTAIN  LH  DCPC  P/N  975GC02Y04,  975GC02Y05,  AND
    975GC02Y06

    For  LH  DCPC P/N  975GC02Y04,  975GC02Y05, and  975GC02Y06  that were
    cleaned before the  effective date of  this AD as  specified in Safran
    Service  Bulletin 975GC02Y-24-018,  or replaced  before the  effective
    date of this AD as specified in Bombardier Service Bulletin 100-24- 29
    or Bombardier Service Bulletin 350-24-004: Within 12 months after  the
    effective  date  of  this  AD,  remove,  replace  with  LH  DCPC   P/N
    975GC02Y08,  test the  DCPC logic  and  protection  cards, and  do the
    functional  test  for  the  LH  DCPC  unit,  in  accordance  with  the
    applicable material specified in paragraphs (h)(1) through (8) of this
    AD. If  any test  fails, do  corrective actions,  and repeat  the test
    before further flight until the test passes.

(l) PARTS INSTALLATION PROHIBITION

    As of 60 days from the effective date of this AD, it is prohibited  to
    install an  LH DCPC  with P/N  975GC02Y04, 975GC02Y05,  975GC02Y06, or
    975GC02Y07, on any airplane.

(m) ADDITIONAL AD PROVISIONS

(1) Alternative Methods of Compliance (AMOCs): The Manager,  International
    Validation 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 International
    Validation Branch, mail it to the address identified in  paragraph (n)
    of this AD. Information may be emailed to: 9-AVS-NYACO-COS@faa.gov.

(2) Contacting the Manufacturer: For any requirement in this AD to  obtain
    instructions   from   a  manufacturer,   the   instructions  must   be
    accomplished using  a method  approved by  the Manager,  International
    Validation Branch,  FAA; or  Transport Canada;  or Bombardier,  Inc.'s
    Transport Canada  Design Approval  Organization (DAO).  If approved by
    the DAO, the approval must include the DAO-authorized signature.

(n) ADDITIONAL INFORMATION

    For  more  information  about  this  AD,  contact  Steven Dzierzynski,
    Aviation  Safety  Engineer,  FAA,  1600  Stewart  Avenue,  Suite  410,
    Westbury,  NY   11590;  telephone   516-228-7300;  email   9-avs-nyaco
    -cos@faa.gov.

(o) 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 this AD specifies otherwise.

(3) The following material was approved for IBR on November 12, 2024.

(i) Bombardier  Service Bulletin  100-24-29, Revision  01, dated  July 27,
    2023.

(ii) Bombardier Service Bulletin  350-24-004, Revision 01, dated  July 27,
     2023.

(iii) Subject  24-61-01  DC  Power   Center  (DCPC)--Removal/Installation,
      Chapter  24--Electrical  Power, Bombardier  Challenger  300 Aircraft
      Maintenance Manual, Part Two,  Publication No. CH 300  AMM, Revision
      82, dated November 9, 2023:

(A) Task 24-61-01-000-801 Removal of the DC Power Center (DCPC);

(B) Task 24-61-01-400-801 Installation of the DC Power Center (DCPC); and

(C) Task 24-61-01-720-801 Functional Test of the DC Power Center (DCPC).

NOTE 1 TO PARAGRAPH (o)(3)(iii): For obtaining the tasks specified in  the
Bombardier  Challenger   300  Aircraft   Maintenance  Manual,   Part  Two,
Publication No. CH 300 AMM, use Document Identification No. CH 300 AMM.

(iv) Subject  24-61-01  DC  Power   Center   (DCPC)--Removal/Installation,
     Chapter  24--Electrical  Power,  Bombardier  Challenger  350 Aircraft
     Maintenance Manual, Part  Two, Publication No.  CH 350 AMM,  Revision
     38, dated November 9, 2023:

(A) Task 24-61-01-000-801 Removal of the DC Power Center (DCPC);

(B) Task 24-61-01-400-801 Installation of the DC Power Center (DCPC); and

(C) Task 24-61-01-720-801 Functional Test of the DC Power Center (DCPC).

NOTE 2 TO PARAGRAPH (o)(3)(iv):  For obtaining the tasks specified  in the
Bombardier  Challenger   350  Aircraft   Maintenance  Manual,   Part  Two,
Publication No. CH 350 AMM, use Document Identification No. CH 350 AMM.

(4) The following material was approved for IBR on August 15, 2023 (88  FR
    44042, July 11, 2023).

(i) Bombardier Service Bulletin 100-24-29, dated April 9, 2021.

(ii) Bombardier Service Bulletin 100-24-30, dated November 29, 2022.

(iii) Bombardier Service Bulletin 350-24-004, dated April 9, 2021.

(iv) Bombardier Service Bulletin 350-24-005, dated November 29, 2022.

(5) For  Bombardier  material identified  in this  AD, contact  Bombardier
    Business Aircraft Customer Response Center, 400 Cote-Vertu Road  West,
    Dorval,  Quebec  H4S   1Y9,  Canada;  telephone   514-855-2999;  email
    ac.yul@aero.bombardier.com; website bombardier.com.

(6) 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.

(7) You may view this material at the National Archives and Records Admin-
    istration (NARA). For information on the availability of this material
    at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations  or
    email fr.inspection@nara.gov.

Issued on September 3, 2024. Victor Wicklund, Deputy Director,  Compliance
& Airworthiness Division, Aircraft Certification Service.

FOR  FURTHER  INFORMATION  CONTACT:  Steven  Dzierzynski,  Aviation Safety
Engineer,  FAA,  1600  Stewart  Avenue,  Suite  410,  Westbury,  NY 11590;
telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.
PREAMBLE 

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-1003; Project Identifier MCAI-2023-00712-T;
Amendment 39-22837; AD 2024-18-03]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2023-11-
01, which applied to certain Bombardier, Inc., Model BD-100-1A10
airplanes. AD 2023-11-01 required a records check and replacement of
affected left-hand (LH) direct current power center (DCPC) units. AD
2023-11-01 also provided optional terminating action for the records
check and replacement. This AD was prompted by multiple reports of
erratic electrical system status on the push button annunciators (PBAs)
and the engine instrument and crew alerting system (EICAS) while on-
ground and during flight, and by the determination that certain DCPC
units require additional modification or replacement. This AD requires
checking maintenance records of certain airplanes, replacing certain
DCPC units, and modifying certain DCPC units. This AD also expands the
applicability of AD 2023-11-01 and 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 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.

The Director of the Federal Register approved the incorporation by
reference of certain other publications listed in this AD as of August
15, 2023 (88 FR 44042, July 11, 2023).

ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-1003; 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, the mandatory continuing airworthiness
information (MCAI), 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 Bombardier material identified in this AD, contact
Bombardier Business Aircraft Customer Response Center, 400 C[ocirc]te-
Vertu Road West, Dorval, Qu[eacute]bec H4S 1Y9, Canada; telephone 514-
855-2999; email bombardier.com">ac.yul@aero.bombardier.com; website bombardier.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-2024-1003.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.

SUPPLEMENTARY INFORMATION:

Background


The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2023-11-01, Amendment 39-22446 (88 FR
44042, July 11, 2023) (AD 2023-11-01). AD 2023-11-01 applied to certain
Bombardier, Inc., Model BD-100-1A10 airplanes. AD 2023-11-01 required a
records check and replacement of affected LH DCPC units, and provided
optional terminating action for those actions. The FAA issued AD 2023-
11-01 to address erratic indications, which could cause the flight crew
to turn off fully-operational electrical power sources, leading to
partial or complete loss of electrical power resulting in loss of
flight displays and reduced controllability of the airplane.

The NPRM published in the Federal Register on April 26, 2024 (89 FR
32380). The NPRM was prompted by AD CF-2023-35, dated May 26, 2023,
issued by Transport Canada, which is the aviation authority for Canada
(Transport Canada AD CF-2023-35) (also referred to as the MCAI). The
MCAI states that airplanes could experience misleading electrical
system status indications (PBA and EICAS) as a result of contamination
of electrical contacts in the LH DCPC internal communication data bus.

In the NPRM, the FAA proposed to continue to require checking the
airplane records and replacement of affected LH DCPC units. The NPRM
also proposed to require modification of certain LH DCPC units,
prohibit installation of affected parts, and expand the applicability
of AD 2023-11-01. The FAA is issuing this AD to address the unsafe
condition on these products.

You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2024-1003.

Discussion of Final Airworthiness Directive

Comments


The FAA received a comment from Bombardier, Inc. (Bombardier), who
also stated its support for the NPRM. The following presents the
comment received on the NPRM and the FAA's response to that comment.

Request To Extend the Compliance Time


Bombardier requested that the proposed AD be revised to extend the
proposed compliance time to March 31, 2026. Bombardier asserted that,
due to changes made in the airplane flight manual (AFM), which
introduced the "Unexpected Electrical Indications" procedure
instructing pilots not to act on erratic indications related to the
electrical power generation and distribution system, the medium risk
was mitigated and the severity of a misleading indication event was
lowered from potentially catastrophic to major. Even if such events
still occur after the implementation of Bombardier Service Bulletins
100-24-30 and 350-24-005, following implementation of the AFM revision,
Bombardier considers these events a reliability issue and stated its
commitment to work with the supplier to correct the effects of such
events. Bombardier further asserted that, when analyzed in conjunction
with the probability of occurrence, the risk becomes low. Additionally,
Bombardier attested that, based on its provisions, a shorter compliance
time will create additional pressure on the U.S. operators, exposing
them to a potential grounding scenario, necessitating the need for
Bombardier to apply for an alternative method of compliance (AMOC) to
support this AD.

The FAA disagrees with the request. Bombardier provided no
substantiating data to support the need for an extension of the
proposed compliance time. In developing an appropriate compliance time
for this action, the FAA considered the safety implications, the time
necessary to accomplish the required actions, the availability of
required parts, and normal maintenance schedules for timely
accomplishment of the required actions. Considering these items, the
FAA has determined that the specified compliance time, as proposed, is
appropriate to ensure an acceptable level of safety. The FAA has not
changed this AD because of this comment. However, under the provisions
of paragraph (m)(1) of this AD, the FAA will consider requests for
approval of alternative compliance times if sufficient data are
submitted to substantiate that the change would provide an acceptable
level of safety.

Conclusion


This product has been approved by the aviation authority of another
country and is approved for operation in the United States. Pursuant to
the FAA's bilateral agreement with this State of Design Authority, it
has notified the FAA of the unsafe condition described in the MCAI
referenced above. The FAA reviewed the relevant data, considered the
comment 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 this product. Except for minor editorial changes,
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 Bombardier Service Bulletins 100-24-29 and 350-24-
004, both Revision 01, both dated July 27, 2023. This material
specifies procedures for a records check to determine the total flight
hours and replacement of affected LH DCPC units (part numbers
975GC02Y04, 975GC0Y05, 975GC02Y06, and 975GC02Y07). These documents are
distinct since they apply to different airplane configurations.

The FAA also reviewed Subject 24-61-01 DC Power Center (DCPC)--
Removal/Installation, Chapter 24--Electrical Power, Bombardier
Challenger 300 Aircraft Maintenance Manual, Part Two, Publication No.
CH 300 AMM, Revision 82, dated November 9, 2023, which specifies:

procedures for removing DCPC units in Task 24-61-01-000-801
Removal of the DC Power Center (DCPC);

procedures for installing DCPC units in Task 24-61-01-400-801
Installation of the DC Power Center (DCPC); and

procedures for testing DCPC units in Task 24-61-01-720-801
Functional Test of the DC Power Center (DCPC).

For obtaining these tasks for the Bombardier Challenger 300
Aircraft Maintenance Manual, Part Two, Publication
No. CH 300 AMM, use Document Identification No. CH 300 AMM.

The FAA also reviewed Subject 24-61-01 DC Power Center (DCPC)--
Removal/Installation, Chapter 24--Electrical Power, Bombardier
Challenger 350 Aircraft Maintenance Manual, Part Two, Publication No.
CH 300 AMM, Revision 38, dated November 9, 2023, which specifies:

procedures for removing DCPC units in Task 24-61-01-000-
801 Removal of the DC Power Center (DCPC);

procedures for installing DCPC units in Task 24-61-01-400-801
Installation of the DC Power Center (DCPC); and

procedures for testing DCPC units in Task 24-61-01-720-801
Functional Test of the DC Power Center (DCPC).

For obtaining these tasks for the Bombardier Challenger 350
Aircraft Maintenance Manual, Part Two, Publication No. CH 350 AMM, use
Document Identification No. CH 350 AMM.

This AD would also require the following material, which the
Director of the Federal Register approved for incorporation by
reference as of August 15, 2023 (88 FR 44042, July 11, 2023).

Bombardier Service Bulletin 100-24-29, dated April 9, 2021.

Bombardier Service Bulletin 100-24-30, dated November 29, 2022.

Bombardier Service Bulletin 350-24-004, dated April 9, 2021.

Bombardier Service Bulletin 350-24-005, dated November 29, 2022.

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 356 airplanes of U.S. registry.

The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

ACTION
LABOR COST
PARTS COST
COST PER PRODUCT
COST ON U.S. OPERATORS
Records check 1 work-hours x $85 per hour = $85
$0
$85
$30,260
New actions (modification) 2 work-hours x $85 per hour = $170
0
170
60,520

The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of any
required actions. The FAA has no way of determining the number of
aircraft that might need this on-condition action:

Estimated Costs of On-Condition Actions

LABOR COST PARTS COST COST PER PRODUCT
7 work-hours x $85 per hour = $595 Up to $35,000 Up to $35,595

According to the manufacturer, some or all of the costs of this AD
may be covered under warranty, 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


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]


2. The FAA amends Sec. 39.13 by:

a. Removing Airworthiness Directive (AD) 2023-11-01, Amendment 39-22446
(88 FR 44042, July 11, 2023); and

b. Adding the following new AD: