[Federal Register Volume 89, Number 58 (Monday, March 25, 2024)]
[Proposed Rules]
[Pages 20562-20565]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-05962]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0758; Project Identifier MCAI-2023-00671-T]
RIN 2120-AA64


Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

[[Page 20563]]


ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Bombardier, Inc., Model BD-100-1A10 airplanes. This 
proposed AD was prompted by the discovery of a single-point failure 
within the left-hand and right-hand heater current monitor (HCM) units. 
This proposed AD would require installing a monitor circuit comprising 
relays external to the HCM units. This proposed AD would also require 
revising the normal and non-normal procedure sections of the existing 
airplane flight manual (AFM) to add new procedures associated with 
revised crew alerting system (CAS) messages. The FAA is proposing this 
AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by May 9, 
2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow 
the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0758; 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 NPRM, the mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For Bombardier service information identified in this 
NPRM, 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 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.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
telephone 516-228-7300; email [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2024-0758; Project Identifier 
MCAI-2023-00671-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to 
Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, 
Suite 410, Westbury, NY 11590; telephone 516-228-7300; email [email protected]. Any commentary that the FAA receives which is not 
specifically designated as CBI will be placed in the public docket for 
this rulemaking.

Background

    Transport Canada, which is the aviation authority for Canada, has 
issued Transport Canada AD CF-2023-33, dated May 10, 2023 (Transport 
Canada AD CF-2023-33) (also referred to after this as the MCAI), to 
correct an unsafe condition on certain Bombardier, Inc., Model BD-100-
1A10 airplanes. The MCAI states that during a review of the air data 
system, Bombardier discovered that a single-point failure exists within 
the left-hand and right-hand HCM units. The HCM unit is designed with a 
single programmable logic device (PLD), which is responsible for the 
control and monitoring functions of the HCM unit. The PLD could fail in 
a way that it would erroneously energize the heater control relay and 
switch the heaters off. This failure could lead to un-annunciated loss 
of ice protection on the air data probes, resulting in the potential 
display of misleading airspeed, and erroneous indications to the 
flightcrew.
    The FAA is proposing 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-2024-0758.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Bombardier Service Bulletin 100-30-06 and 
Bombardier Service Bulletin 350-30-001, both dated December 29, 2022. 
The service information specifies procedures to install a monitoring 
circuit comprising relays external to the HCM units, including 
reworking the plate assembly, installing relay bracket assemblies, 
installing relays and a rail terminal module, installing wires for the 
relays, and performing operational testing. These documents are 
distinct since they apply to different airplane serial numbers.
    The FAA also reviewed the following service information, which 
specifies new normal procedures to follow after installation of the 
monitoring circuit. These documents are distinct since they apply to 
different airplane serial numbers.
     BEFORE STARTING ENGINES section, Subsection 04-02, Chapter 
4, Normal Procedures, Bombardier Challenger 300 AFM (Imperial Version), 
Publication No. CSP 100-1, Revision 72, dated May 11, 2023. (For 
obtaining the procedures for Bombardier Challenger 300 AFM (Imperial 
Version), Publication No. CSP 100-1, use Document Identification No. CH 
300 AFM-I.)

[[Page 20564]]

     BEFORE STARTING ENGINES section, Subsection 04-02, Chapter 
4, Normal Procedures, Bombardier Challenger 350 AFM, Publication No. CH 
350 AFM, Revision 38, dated May 11, 2023. (For obtaining the procedures 
for Bombardier Challenger 350 AFM, Publication No. CH 350 AFM, use 
Document Identification No. CH 350 AFM.)
    The FAA reviewed the following service information, which specifies 
non-normal procedures to follow after installation of the monitoring 
circuit. These documents are distinct since they apply to different 
airplane serial numbers.
     Subsection 05-27, Ice & Rain Protection, Chapter 5, Non-
Normal Procedures, Bombardier Challenger 300 AFM (Imperial Version), 
Publication No. CSP 100-1, Revision 72, dated May 11, 2023. (For 
obtaining the procedures for Bombardier Challenger 300 AFM (Imperial 
Version), Publication No. CSP 100-1, use Document Identification No. CH 
300 AFM-I.)
     Subsection 05-27, Ice & Rain Protection, Chapter 5, Non-
Normal Procedures, Bombardier Challenger 350 AFM, Publication No. CH 
350 AFM, Revision 38, dated May 11, 2023. (For obtaining the procedures 
for Bombardier Challenger 350 AFM, Publication No. CH 350 AFM, use 
Document Identification No. CH 350 AFM.)
    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 the ADDRESSES section.

FAA's Determination

    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 and 
service information referenced above. The FAA is issuing this NPRM 
after determining that the unsafe condition described previously is 
likely to exist or develop on other products of the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information already described. This AD also requires 
revising the existing AFM.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 343 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                      Estimated Costs for Required Actions
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            Labor cost                    Parts cost          Cost per product        Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Up to 70 work-hours x $85 per hour  Up to $2,324.........  Up to $8,274.........  Up to $2,837,982.
 = Up to $5,950.00.
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    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all the costs of this 
proposed 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.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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:

Bombardier, Inc.: Docket No. FAA-2024-0758; Project Identifier MCAI-
2023-00671-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by May 9, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Bombardier, Inc., Model BD-100-1A10 
airplanes, certificated in any category, serial numbers 20003 
through 20936 inclusive.

(d) Subject

    Air Transport Association (ATA) of America Code 30, Ice and Rain 
Protection.

(e) Unsafe Condition

    This AD was prompted by a review of the air data system where 
Bombardier discovered that a single-point failure exists within the 
left-hand and right-hand heater current monitor (HCM) units. The FAA 
is issuing this AD to address the failure of the programmable logic 
device in the left-hand and right-hand HCM units. The unsafe 
condition, if not addressed, could lead to un-annunciated loss of 
ice protection on the air data probes, resulting in the potential 
display of misleading airspeed, and erroneous indications to the 
flightcrew.

[[Page 20565]]

(f) Compliance

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

(g) Monitoring Circuit Installation and Tests

    Within 60 months from the effective date of this AD, install a 
monitoring circuit comprising relays external to the HCM units, in 
accordance with sections 2.B. and 2.C. of the Accomplishment 
Instructions of the applicable service information specified in 
paragraph (g)(1) or (2) of this AD.
    (1) Bombardier Service Bulletin 100-30-06, dated December 29, 
2022 (for airplane serial numbers 20003 through 20500 inclusive).
    (2) Bombardier Service Bulletin 350-30-001, dated December 29, 
2022 (for airplane serial numbers 20501 through 20936 inclusive); as 
applicable.

(h) Revision of Existing Airplane Flight Manual (AFM)

    Within 60 months from the effective date of this AD, and after 
the completion of the actions required by paragraph (g) of this AD, 
revise the existing AFM as specified in paragraphs (h)(1) through 
(4) of this AD, as applicable.
    (1) For airplane serial numbers 20003 through 20500 inclusive: 
Revise Chapter 4, Normal Procedures, to include the information in 
BEFORE STARTING ENGINES section, Subsection 04-02, Bombardier 
Challenger 300 AFM (Imperial Version), Publication No. CSP 100-1, 
Revision 72, dated May 11, 2023.
    Note 1 to paragraph (h)(1): For obtaining the procedures 
specified in paragraphs (h)(1) and (2) of this AD for Bombardier 
Challenger 300 AFM (Imperial Version), Publication No. CSP 100-1, 
use Document Identification No. CH 300 AFM-I.
    (2) For airplane serial numbers 20003 through 20500 inclusive: 
Revise Chapter 5, Non-Normal Procedures, to include the information 
in Subsection 05-27, Ice & Rain Protection, Bombardier Challenger 
300 AFM (Imperial Version), Publication No. CSP 100-1, Revision 72, 
dated May 11, 2023.
    (3) For airplane serial numbers 20501 through 20936 inclusive: 
Revise Chapter 4, Normal Procedures, to include the information in 
BEFORE STARTING ENGINES section, Subsection 04-02, Bombardier 
Challenger 350, Publication No. CH 350 AFM, Revision 38, dated May 
11, 2023.
    Note 2 to paragraph (h)(3): For obtaining the procedures 
specified in paragraphs (h)(3) and (4) of this AD for Bombardier 
Challenger 350 AFM, Publication No. CH 350 AFM, use Document 
Identification No. CH 350 AFM.
    (4) For airplane serial numbers 20501 through 20936 inclusive: 
Revise Chapter 5, Non-Normal Procedures, to include the information 
in Subsection 05-27, Ice & Rain Protection, Bombardier Challenger 
350, Publication No. CH 350 AFM, Revision 38, dated May 11, 2023.

(i) Additional AD Provisions

    The following provisions also apply to this AD:
    (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 (j)(2) of this AD. Information may be emailed to: 9-
[email protected]. Before using any approved AMOC, notify your 
appropriate principal inspector, or lacking a principal inspector, 
the manager of the responsible Flight Standards Office.
    (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.

(j) Additional Information

    (1) Refer to Transport Canada AD CF-2023-33, dated May 10, 2023, 
for related information. This Transport Canada AD may be found in 
the AD docket at regulations.gov under Docket No. FAA-2024-0758.
    (2) 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 [email protected].

(k) 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.
    (i) BEFORE STARTING ENGINES section, Subsection 04-02, Chapter 
4, Normal Procedures, Bombardier Challenger 300 AFM (Imperial 
Version), Publication No. CSP 100-1, Revision 72, dated May 11, 
2023.
    Note 3 to paragraph (k)(2)(i): For obtaining the procedures 
specified in paragraphs (k)(2)(i) and (ii) of this AD for Bombardier 
Challenger 300 AFM (Imperial Version), Publication No. CSP 100-1, 
use Document Identification No. CH 300 AFM-I.
    (ii) Subsection 05-27, Ice & Rain Protection, Chapter 5, Non-
Normal Procedures, Bombardier Challenger 300 AFM (Imperial Version), 
Publication No. CSP 100-1, Revision 72, dated May 11, 2023.
    (iii) BEFORE STARTING ENGINES section, Subsection 04-02, Chapter 
4, Normal Procedures, Bombardier Challenger 350 AFM, Publication No. 
CH 350 AFM, Revision 38, dated May 11, 2023.
    Note 4 to paragraph (k)(2)(iii): For obtaining the procedures 
specified in paragraphs (k)(2)(iii) and (iv) of this AD for 
Bombardier Challenger 350 AFM, Publication No. CH 350 AFM, use 
Document Identification No. CH 350 AFM.
    (iv) Subsection 05-27, Ice & Rain Protection, Chapter 5, Non-
Normal Procedures, Bombardier Challenger 350 AFM, Publication No. CH 
350 AFM, Revision 38, dated May 11, 2023.
    (v) Bombardier Service Bulletin 100-30-06, dated December 29, 
2022.
    (vi) Bombardier Service Bulletin 350-30-001, dated December 29, 
2022.
    (3) For service information 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.
    (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 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 March 15, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-05962 Filed 3-22-24; 8:45 am]
BILLING CODE 4910-13-P