[Federal Register Volume 90, Number 64 (Friday, April 4, 2025)]
[Rules and Regulations]
[Pages 14719-14723]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-05852]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0346; Project Identifier MCAI-2025-00052-E; 
Amendment 39-23003; AD 2025-07-02]
RIN 2120-AA64


Airworthiness Directives; BRP-Rotax GmbH & Co KG (Formerly BRP-
POWERTRAIN GMBH & CO KG and Bombardier-Rotax GmbH) Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain BRP-Rotax GmbH & Co KG (Rotax) Model 912 iSc2 Sport, 912 iSc3 
Sport, 915 iSc2 C24, and 915 iSc3 C24 engines. This AD was prompted by 
a report of deviations during the manufacturing process that caused 
incorrect application of a certain thread-locker to certain sprag 
clutch housing and oil spray nozzles. This AD requires repetitive 
operational checks of the battery backup function with removal of the 
engine from service if insufficient battery power is found, one-time 
inspections of the oil spray nozzle and generator stator assembly, and, 
depending on the results of the inspections, replacement with parts 
eligible for installation. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective April 21, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of April 21, 
2025.
    The FAA must receive comments on this AD by May 19, 2025.

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

[[Page 14720]]

No. FAA-2025-0346; 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 
street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For Rotax material identified in this AD, contact Rotax, 
Rotaxstrasse 1, A-4623 Gunskirchen, Austria; phone: +43 7246 601 0; 
website: flyrotax.com.
     You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (817) 222-5110. It is also available at 
regulations.gov under Docket No. FAA-2025-0346.

FOR FURTHER INFORMATION CONTACT: Kenneth Steeves, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: (781) 238-7765; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments to an address listed under 
ADDRESSES. Include ``Docket No. FAA-2025-0346; Project Identifier MCAI-
2025-00052-E'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the final rule, 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 
this final rule 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 final rule.

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Kenneth 
Steeves, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590. Any commentary that the FAA receives which is not 
specifically designated as CBI will be placed in the public docket for 
this rulemaking.

Background

    The European Union Aviation Safety Agency (EASA), which is the 
Technical Agent for the Member States of the European Union, has issued 
EASA Emergency AD 2025-0019-E, dated January 16, 2025 (referred to 
after this as the MCAI), to address an unsafe condition on Rotax 912 
iSc Sport, 915 iSc A, 915 iSc C24, 916 iSc A, 916 iSc B, and 916 iSc 
C24 series engines, all models, all serial numbers. The MCAI states 
that the manufacturer reported an occurrence from the production line 
of an excessive amount of thread-locker applied at the sprag clutch 
housing and oil spray nozzle of several engines. Further investigation 
by the manufacturer revealed that this abnormality was caused by a 
deviation in the manufacturing process. Improper application of thread-
locker can cause blockage of the oil nozzle, potentially leading to 
inadequate cooling and damage to the generators. This condition, if not 
corrected, could lead to engine in-flight shutdown and forced landing, 
damage to the airplane, and injury to the occupants.
    The FAA is also permitting the owner/operator (pilot) holding at 
least a private pilot certificate to perform an operational check to 
ensure the availability of the battery backup function in accordance 
with paragraph (g)(1) of this AD. The FAA is also requiring that 
compliance with the applicable paragraphs of this AD be entered into 
the engine maintenance records in accordance with 14 CFR 43.9(a) and 
91.417(a)(2)(v). This action could be performed equally well by a pilot 
or a mechanic. This is an exception to the FAA's standard maintenance 
regulations.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2025-0346.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed Rotax Alert Service Bulletin ASB-912 i-016 R1/ASB-
915 i-016 R1/ASB-916 i-006 R1, Revision 1, dated December 20, 2024 
(published as a single document). This material specifies procedures 
for performing an operational check of the battery backup function, 
inspecting the oil spray nozzle and generator stator assembly, and 
replacing the oil spray nozzle.
    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.

FAA's Determination

    These products have been approved by the aviation authority of 
another country and are 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 is issuing this AD after determining 
that the unsafe condition described previously is likely to exist or 
develop on other products of the same type design.

AD Requirements

    This AD requires repetitive operational checks of the battery 
backup function with removal of the engine from service if insufficient 
battery power is found, one-time inspections of the oil spray nozzle 
and generator stator assembly, and, depending on the results of the 
inspections, replacement with parts eligible for installation.

Differences Between This AD and the MCAI

    Where the MCAI applies to Rotax Model 915 iSc A, 916 iSc A, 916 iSc 
B and 916 iSc C24 series engines, all models, all serial numbers, this 
AD does not, as these engine models do not have an FAA type 
certificate.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 
551 et seq.) authorizes agencies to dispense with notice and comment 
procedures for rules when the agency, for ``good cause,'' finds that 
those procedures are ``impracticable, unnecessary, or contrary to the 
public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to

[[Page 14721]]

make rules effective in less than thirty days, upon a finding of good 
cause.
    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies forgoing notice and comment prior to adoption of this rule 
because deviations during the manufacturing process of certain sprag 
clutch housing and oil spray nozzles could cause blockage of the oil 
nozzle and damage to the generators which, if not corrected, could lead 
to engine in-flight shutdown and forced landing, damage to the 
airplane, and injury to the occupants. Since this condition can result 
rapidly and without warning, the FAA has determined that these engines 
will need to be inspected within 25 flight hours or within 12 months, 
whichever occurs first after the effective date of this AD. These 
compliance times are shorter than the time necessary for the public to 
comment and for publication of the final rule. Accordingly, notice and 
opportunity for prior public comment are impracticable and contrary to 
the public interest pursuant to 5 U.S.C. 553(b).
    In addition, the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days, 
for the same reasons the FAA found good cause to forgo notice and 
comment.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because the FAA has determined 
that it has good cause to adopt this rule without prior notice and 
comment, RFA analysis is not required.

Costs of Compliance

    The FAA estimates that this AD affects 25 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspect oil spray nozzle and generator  8.50 work-hours x $85                 $0         $722.50      $18,062.50
 stator assembly.                        per hour = $722.50.
----------------------------------------------------------------------------------------------------------------

    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 engines 
that might need these replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace oil spray nozzle......................  8 work-hours x $85 per hour =               $500          $1,180
                                                 $680.
Replace generator stator assembly.............  8 work-hours x $85 per hour =              2,000           2,680
                                                 $680.
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this 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

    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, and
    (2) Will not affect intrastate aviation in Alaska.

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:

2025-07-02 BRP-Rotax GmbH & Co KG (formerly BRP-POWERTRAIN GMBH & CO 
KG and Bombardier-Rotax GmbH): Amendment 39-23003; Docket No. FAA-
2025-0346; Project Identifier MCAI-2025-00052-E.

(a) Effective Date

    This airworthiness directive (AD) is effective April 21, 2025.

[[Page 14722]]

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to BRP-Rotax GmbH & Co KG (formerly BRP-
POWERTRAIN GMBH & CO KG and Bombardier-Rotax GmbH) (Rotax) Model 912 
iSc2 Sport, 912 iSc3 Sport, 915 iSc2 C24, and 915 iSc3 C24 engines 
that are equipped with an affected part as defined in paragraph 
(h)(1) of this AD.

(d) Subject

    Joint Aircraft System Component (JASC) Code 8120, Exhaust 
Turbocharger; 8550, Reciprocating Engine Oil System.

(e) Unsafe Condition

    This AD was prompted by a report of deviations during the 
manufacturing process of certain sprag clutch housing and oil spray 
nozzles, including incorrect application of a certain thread-locker. 
The FAA is issuing this AD to prevent blockage of the oil nozzle, 
inadequate cooling, and damage to the generators. The unsafe 
condition, if not addressed, could result in engine in-flight 
shutdown and forced landing, damage to the airplane, and injury to 
the occupants.

(f) Compliance

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

(g) Required Actions

    (1) Before further flight after the effective date of this AD 
and thereafter before each flight, perform a first start of the 
battery prior to starting the engine under normal procedure as an 
operational check to ensure the availability of the battery backup 
function.
    (i) In order to check the sufficient state of battery capacity, 
do not use an additional external power source for this operational 
check.
    (ii) The owner/operator (pilot) holding at least a private pilot 
certificate may perform the action required by paragraph (g)(1) of 
this AD for your engine and must enter compliance with the 
applicable paragraphs of this AD into the engine maintenance records 
in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The record 
must be maintained as required by 14 CFR 91.417, 121.380, or 
135.439.
    (2) If, during the operational check required by paragraph 
(g)(1) of this AD, the battery capacity is determined to be 
insufficient, before further flight, remove the engine from service.
    (3) Within 25 flight hours or 12 months, whichever occurs first 
after the effective date of this AD, perform a one-time inspection 
of the oil spray nozzle in accordance with the Accomplishment/
Instructions, paragraph 3.4.1) of Rotax Alert Service Bulletin ASB-
912 i-016 R1/ASB-915 i-016 R1/ASB-916 i-006 R1, Revision 1, dated 
December 20, 2024 (published as a single document) (Rotax ASB-912 i-
016 R1/ASB-915 i-016 R1/ASB-916 i-006 R1).
    (4) If, during the inspection required by paragraph (g)(3) of 
this AD, any oil spray nozzle fails to meet the serviceability 
criteria specified in the Accomplishment/Instructions, paragraph 
3.4.1) of Rotax ASB-912 i-016 R1/ASB-915 i-016 R1/ASB-916 i-006 R1, 
before further flight, replace the oil spray nozzle with a part 
eligible for installation, in accordance with the Accomplishment/
Instructions, paragraph 3.5.2) of Rotax ASB-912 i-016 R1/ASB-915 i-
016 R1/ASB-916 i-006 R1.
    (5) Within 25 flight hours or 12 months, whichever occurs first 
after the effective date of this AD, perform a one-time inspection 
of the generator stator assembly in accordance with the 
Accomplishment/Instructions, paragraph 3.5.1) of Rotax ASB-912 i-016 
R1/ASB-915 i-016 R1/ASB-916 i-006 R1.
    (6) If, during the inspection required by paragraph (g)(6) of 
this AD, any generator stator assembly fails to meet the 
serviceability criteria specified in the Accomplishment/
Instructions, paragraph 3.5.1) of Rotax ASB-912 i-016 R1/ASB-915 i-
016 R1/ASB-916 i-006 R1, before further flight, replace the 
generator stator assembly with a part eligible for installation.

    Note 1 to paragraph (g)(6): Guidance for removal and 
installation of the generator stator assembly for Rotax Model 912 
iSc2 Sport and 912 iSc3 Sport engines may be found in Rotax Heavy 
Maintenance Manual MMH-912i, Part No. 898752, Chapter 24-20-00. 
Guidance for removal and installation of the generator stator 
assembly for Rotax Model 915 iSc2 C24 and 915 iSc3 C24 engines may 
be found in the Rotax Heavy Maintenance Manual MMH-915 I A/C24, Part 
No. 898861, Chapter 24-20-00.

(h) Definitions

    (1) For the purpose of this AD, an ``affected part'' is a 
generator stator assembly, or an oil spray nozzle assembly having 
part number (P/N) 456540 manufactured before October 31, 2024, that 
is:
    (i) Installed on an engine with a serial number specified in the 
Appendix to Rotax ASB-912 i-016 R1/ASB-915 i-016 R1/ASB-916 i-006 
R1; or
    (ii) Known to have been delivered as a spare part, as specified 
in Planning Information, Paragraph 1.1, Criterion B), of Rotax ASB-
912 i-016 R1/ASB-915 i-016 R1/ASB-916 i-006 R1; or
    (iii) Unable to be excluded from the criteria listed in 
paragraph (h)(1)(i) or (ii) of this AD.
    (iv) A generator stator assembly or an oil spray nozzle assembly 
is not considered an ``affected part'' if it has been in operation 
for 200 flight hours or more without a required maintenance action 
due to generator stator assembly cooling issues.
    (2) For the purpose of this AD, a ``part eligible for 
installation'' is any of the following:
    (i) An oil spray nozzle having P/N 456540, manufactured after 
October 31, 2024.
    (ii) For Rotax Model 912 iSc2 Sport and 912 iSc3 Sport engines, 
a generator stator assembly having P/N 891095.
    (iii) For Rotax Model 915 iSc2 C24 and 915 iSc3 C24 engines, a 
generator stator assembly having P/N 889562.

(i) Terminating Action

    The actions specified in paragraphs (g)(3) through (6) of this 
AD constitute terminating action for all the requirements of 
paragraph (g)(1) of this AD.

(j) Credit for Previous Actions

    You may take credit for the actions required by paragraphs 
(g)(3) through (6) of this AD if you performed those actions before 
the effective date of this AD using Rotax Service Bulletin SB-912 i-
016/SB-915 i-016/SB-916 i-006, dated December 16, 2024 (published as 
a single document).

(k) 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 local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (l)(1) of 
this AD and email to: [email protected].

(l) Additional Information

    (1) For more information about this AD, contact Kenneth Steeves, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (781) 238-7765; email: 
[email protected].
    (2)) Material identified in this AD that is not incorporated by 
reference is available at the address specified in paragraph (m)(3) 
of this AD.

(m) 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 the AD specifies otherwise.
    (i) BRP-Rotax GmbH & Co KG (Rotax) Alert Service Bulletin ASB-
912 i-016 R1/ASB-915 i-016 R1/ASB-916 i-006 R1, Revision 1, dated 
December 20, 2024 (published as a single document).
    (ii) [Reserved]
    (3) For Rotax material identified in this AD, contact BRP-Rotax 
GmbH & Co KG, Rotaxstrasse 1, A-4623 Gunskirchen, Austria; phone: 
+43 7246 601 0; website: flyrotax.com.
    (4) You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (817) 222-5110.
    (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].


[[Page 14723]]


    Issued on April 1, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-05852 Filed 4-1-25; 4:15 pm]
BILLING CODE 4910-13-P