
[Federal Register Volume 88, Number 222 (Monday, November 20, 2023)]
[Rules and Regulations]
[Pages 80579-80582]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-25494]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1404; Project Identifier MCAI-2023-00451-T; 
Amendment 39-22584; AD 2023-21-12]
RIN 2120-AA64


Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate 
Previously Held by Bombardier, Inc.) Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
MHI RJ Aviation ULC Model CL-600-2B19 (Regional Jet Series 100 & 440) 
airplanes. This AD was prompted by a report of missing insulation in 
the engine pylon area. This AD requires, for certain airplanes, 
inspecting the engine pylon structure for discrepancies and repair if 
necessary. This AD also requires revising the existing maintenance or 
inspection program, as applicable, to incorporate a new certification 
maintenance requirement (CMR) task. The FAA is issuing this AD to 
address the unsafe condition on these products.

DATES: This AD is effective December 26, 2023.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of December 26, 
2023.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-1404; 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 service information identified in this final rule, 
contact MHI RJ Aviation Group, Customer Response Center, 3655 Ave. des 
Grandes-Tourelles, Suite 110, Boisbriand, Qu[eacute]bec J7H 0E2 Canada; 
North America toll-free telephone 833-990-7272 or direct-dial telephone 
450-990-7272; email: mhirj.com">thd.crj@mhirj.com; website: mhirj.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-2023-1404.

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

SUPPLEMENTARY INFORMATION: 

[[Page 80580]]

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 MHI RJ Aviation ULC 
Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. The NPRM 
published in the Federal Register on July 12, 2023 (88 FR 44226). The 
NPRM was prompted by AD CF-2023-19, dated March 13, 2023 (Transport 
Canada AD CF-2023-19) (also referred to after this as the MCAI), issued 
by Transport Canada, which is the aviation authority for Canada. The 
MCAI states there was a report of a missing 12-inch piece of insulation 
in the 14th stage bleed ducts installed in both left hand (LH) and 
right hand (RH) engine pylon areas.
    In the NPRM, the FAA proposed to require, for certain airplanes, 
inspecting the engine pylon structure for discrepancies and repair if 
necessary. The NPRM also proposed to require revising the existing 
maintenance or inspection program, as applicable, to incorporate a new 
CMR task.
    The FAA is issuing this AD to address missing or damaged insulation 
in the engine pylon area. The unsafe condition, if not addressed, could 
result in the bleed duct to radiate heat to the surrounding structure 
and, if not corrected, could lead to the loss of the structural 
integrity of the engine pylon and possible loss of the engine.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2023-1404.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Air Line Pilots Association, 
International (ALPA) who supported the NPRM without change.
    The FAA received additional comments from Air Wisconsin Airlines 
and MHI RJ Aviation ULC (MHI RJ). The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request To Refer New Temporary Revision

    MHI RJ requested that the FAA revise the proposed AD to refer to 
MHI RJ Temporary Revision 2A-77, dated May 8, 2023, which was issued to 
revise the phase-in (initial) compliance time in MHI RJ Temporary 
Revision 2A-76, dated September 29, 2022, from 40 months to 48 months.
    The FAA concurs with the request and has revised paragraph (h) of 
this AD to refer to MHI RJ Temporary Revision 2A-77, dated May 8, 2023, 
for the new CMR task. The FAA has also provided credit for using MHI RJ 
Temporary Revision 2A-76, dated September 29, 2022, in paragraph (j)(2) 
of this AD. The CMR task and interval is the same in both temporary 
revisions. In addition, there is no change to initial compliance time 
because paragraph (j) of the proposed AD did not refer to MHI RJ 
Temporary Revision 2A-76, dated September 29, 2022, for the initial 
compliance time and instead specified ``The initial compliance time for 
doing the task is within 48 months or 6,600 flight hours, whichever 
occurs first after the effective date of this AD.'' The compliance time 
change in MHI RJ Temporary Revision 2A-77, dated May 8, 2023, is within 
the initial compliance time specified in this AD.

Request To Revise Compliance Time

    MHI RJ stated it noticed that the FAA is re-starting the clock in 
paragraph (h) of the proposed AD from the effective date of the AD 
rather than the issue date of the temporary revision: MHI RJ states 
that the task interval should start from September 29, 2022, which is 
the issue date of MHI RJ Temporary Revision 2A-76. MHI RJ stated that, 
in this particular case, the start of the compliance from September 29, 
2022, is critical for safety. The FAA infers that MHI RJ is requesting 
that the agency reduce the initial compliance time specified in 
paragraph (h) of this AD by referring to the September 29, 2022, date 
instead of the effective date of this AD.
    The FAA acknowledges MHI RJ's concern. However, reducing the 
compliance time in paragraph (h) of this AD would result in a more 
restrictive compliance time that would necessitate issuing a 
supplemental NPRM, delaying the issuance of the final rule. Since the 
detailed visual inspection of spar FS654.50, spar FS672.20, and the 
firewall for discrepancies specified in paragraph (g) of this AD would 
be delayed if a supplemental NPRM is issued, any increase in the level 
of safety by reducing the compliance time in paragraph of (h) of this 
AD may be offset by delaying the inspections in paragraph (g) of this 
AD. The FAA has determined to delay this action is not appropriate in 
this case as the compliance times in this AD will ensure an acceptable 
level of safety.

Request To Clarify Compliance Time

    Air Wisconsin Airlines asked if the ``40 months'' specified in MHI 
RJ Temporary Revision 2A-76, dated September 29, 2022, is in error. Air 
Wisconsin Airlines noted that both paragraphs (g) and (h) of the 
proposed AD mention ``within 48 months.''
    The FAA agrees to clarify. As stated previously, MHI RJ Temporary 
Revision 2A-76, dated September 29, 2022, was revised by MHI RJ 
Temporary Revision 2A-77, dated May 8, 2023, to correct the ``40 
months'' and change it to ``48 months.'' The FAA has not changed this 
AD in this regard.

Request To Revise Language in Paragraph (e) of the Proposed AD

    MHI RJ requested that the proposed AD should not only mention 
missing insulation but damaged insulation as well and stated the 
sentence in paragraph (e) of the proposed AD should read: ``The FAA is 
issuing this AD to address missing or damaged insulation in the engine 
pylon area.''
    The FAA concurs and has revised paragraph (e) of this AD 
accordingly. The tasks associated with the new CMR task specifies 
inspecting for damaged insulation as well as missing insulation. 
Therefore, it is accurate to state that the FAA is issuing this AD to 
address both conditions.

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 
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 this product. 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 MHI RJ Service Bulletin 601R-54-006, Revision A, 
dated May 24, 2023. This service information specifies procedures for 
doing a detailed visual inspection of spar FS654.50, spar FS672.20, and 
the firewall for discrepancies, including corrosion, cracks, web 
waviness or flatness and damaged fasteners.
    The FAA reviewed MHI RJ Temporary Revision 2A-77, dated May 8, 
2023. This service information specifies a new CMR task, number C36-12-
133-01, ``Detailed Visual Inspection for missing insulation/heat shield 
on the 14th stage bleed duct, running through the pylon area between 
FS654 and FS672.''

[[Page 80581]]

    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.

Costs of Compliance

    The FAA estimates that this AD affects 338 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                     Estimated Costs for Required Actions *
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                                                                                    Cost per       Cost on U.S.
                          Labor cost                              Parts cost        product         operators
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6 work-hours x $85 per hour = $510...........................              $0             $510         $172,380
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* This table does not include the cost of revising the existing maintenance or inspection program.

    The FAA has determined that revising the existing maintenance or 
inspection program takes an average of 90 work-hours per operator, 
although the agency recognizes that this number may vary from operator 
to operator. Since operators incorporate maintenance or inspection 
program changes for their affected fleet(s), the FAA has determined 
that a per-operator estimate is more accurate than a per-airplane 
estimate. Therefore, the agency estimates the average total cost per 
operator to be $7,650 (90 work-hours x $85 per work-hour).
    The FAA has received no definitive data on which to base the cost 
estimates for the on-condition repairs specified in this AD.

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 adding the following new airworthiness 
directive:

2023-21-12 MHI RJ Aviation ULC (Type Certificate Previously Held by 
Bombardier, Inc.): Amendment 39-22584; Docket No. FAA-2023-1404; 
Project Identifier MCAI-2023-00451-T.

(a) Effective Date

    This airworthiness directive (AD) is effective December 26, 
2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all MHI RJ Aviation ULC (Type Certificate 
previously held by Bombardier, Inc.) Model CL-600-2B19 (Regional Jet 
Series 100 & 440) airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code: 36, Pneumatic.

(e) Unsafe Condition

    This AD was prompted by a report of missing insulation in the 
engine pylon area. The FAA is issuing this AD to address missing or 
damaged insulation in the engine pylon area. The unsafe condition, 
if not addressed, could result in the bleed duct to radiate heat to 
the surrounding structure and, if not corrected, could lead to the 
loss of the structural integrity of the engine pylon and possible 
loss of the engine.

(f) Compliance

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

(g) Detailed Visual Inspection

    For airplanes having serial numbers 7031, 7045, 7069, 7078, 
7089, 7102, 7110, 7168, 7188, 7203, 7212, 7217, 7229, 7231, 7236, 
7243, 7257, 7258, 7269, 7271, 7276, 7284, 7290, 7302, 7304, 7306, 
7310, 7328, 7339, 7342, 7355, 7358, 7360, 7401, 7404, 7437, 7441, 
7448, 7458, 7474, 7476, 7479, 7495, 7502, 7503, 7517, 7527, 7530, 
7532, 7548, 7551, 7574, 7575, 7579, 7582, 7586, 7588, 7599, 7600, 
7606, 7609, 7623, 7632, 7648, 7657, 7658, 7664, 7667, 7674, 7681, 
7682, 7683, 7687, 7715, 7727, 7743, 7748, 7749, 7750, 7758, 7760, 
7769, 7780, 7810, 7817, 7818, 7821, 7822, 7857, 7859, 7871, 7873, 
7889, 7892, 7895, 7909, 7912, 7913, 7920, 7922, 7923, 7926, 7929, 
7932, 7935, 7937, 7954, 7961, 7964, and 8011: Within 48 months or 
6,600 flight hours, whichever occurs first after the effective date 
of this AD, do a detailed visual inspection for discrepancies of 
spar FS654.50, spar FS672.20, and the firewall, in accordance with 
Section 2.B. of the Accomplishment Instructions of MHI RJ Service 
Bulletin 601R-54-006, Revision A, dated May 24, 2023. If any 
discrepancies are found, before further flight, repair using a 
method approved by the Manager, International Validation Branch, 
FAA; or Transport Canada or MHI RJ Aviation ULC's Transport Canada 
Design Approval Organization (DAO). If approved by the DAO, the 
approval must include the DAO-authorized signature.

(h) Maintenance or Inspection Program Revision

    Within 60 days after the effective date of this AD, revise the 
existing maintenance or

[[Page 80582]]

inspection program, as applicable, to incorporate the information 
specified in MHI RJ Temporary Revision 2A-77, dated May 8, 2023, for 
certification maintenance requirements task number C36-12-133-01. 
The initial compliance time for doing the task is within 48 months 
or 6,600 flight hours, whichever occurs first after the effective 
date of this AD.

(i) No Alternative Actions or Intervals

    After the existing maintenance or inspection program has been 
revised as required by paragraph (h) of this AD, no alternative 
actions (e.g., inspections) or intervals may be used unless the 
actions and intervals are approved as an alternative method of 
compliance (AMOC) in accordance with the procedures specified in 
paragraph (k)(1) of this AD.

(j) Credit for Previous Actions

    (1) This paragraph provides credit for actions required by 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using MHI RJ Service Bulletin 601R-54-006, 
dated September 13, 2022.
    (2) This paragraph provides credit for actions required by 
paragraph (h) of this AD, if those actions were performed before the 
effective date of this AD using MHI RJ Temporary Revision 2A-76, 
dated September 29, 2022.

(k) 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, 
International Validation Branch, mail it to the address identified 
in paragraph (l)(2) of this AD or email to: [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 MHI RJ Aviation ULC's 
Transport Canada DAO. If approved by the DAO, the approval must 
include the DAO-authorized signature.

(l) Additional Information

    (1) Refer to Transport Canada AD CF-2023-19, dated March 13, 
2023, for related information. This Transport Canada AD may be found 
in the AD docket at regulations.gov under Docket No. FAA-2023-1404.
    (2) For more information about this AD, contact Fatin Saumik, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; telephone 516-228-7300; email [email protected].

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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) MHI RJ Service Bulletin 601R-54-006, Revision A, dated May 
24, 2023.
    (ii) MHI RJ Temporary Revision 2A-77, dated May 8, 2023.
    (3) For service information identified in this AD, contact MHI 
RJ Aviation Group, Customer Response Center, 3655 Ave. des Grandes-
Tourelles, Suite 110, Boisbriand, Qu[eacute]bec J7H 0E2 Canada; 
North America toll-free telephone 833-990-7272 or direct-dial 
telephone 450-990-7272; email: mhirj.com">thd.crj@mhirj.com; website: 
mhirj.com.
    (4) 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.
    (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 October 20, 2023.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2023-25494 Filed 11-17-23; 8:45 am]
BILLING CODE 4910-13-P


