DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0316; Project Identifier MCAI-2020-00461-E]
RIN 2120-AA64

Airworthiness Directives; GE Aviation Czech s.r.o. (Type
Certificate Previously Held by WALTER Engines a.s., Walter a.s., and
MOTORLET a.s.) Turboprop Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all GE Aviation Czech s.r.o. (GEAC) H75-200, H80-100, and H80-200
model turboprop engines. This proposed AD was prompted by several
reports of engine gas generator speed (Ng) rollbacks occurring below
idle on GEAC H75-200, H80-100, and H80-200 model turboprop engines.
This proposed AD would require an inspection of a certain part number
(P/N) fuel control unit (FCU) and, if deficiencies are detected,
replacement of the FCU with a part eligible for installation. 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 June 4,
2021.

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 https://www.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.

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.

For service information identified in this NPRM, contact GE
Aviation Czech, Beranov[yacute]ch 65 199 02 Praha 9--Let[ncaron]any,
Czech Republic; phone: +420 222 538 111. You may view this service
information 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 (781)
238-7759.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0316; 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.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aviation Safety
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803;
phone: (781) 238-7146; fax: (781) 238-7199; email:
barbara.caufield@faa.gov.

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-2021-0316; Project Identifier
MCAI-2020-00461-E" 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 this
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
https://www.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
Barbara Caufield, Aviation Safety Engineer, ECO Branch, FAA, 1200
District Avenue, Burlington, MA 01803. 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 Community, has
issued EASA AD 2020-0082, dated April 1, 2020 (referred to after this
as "the MCAI"), to address the unsafe condition on these products.
The MCAI states:

Several occurrences have been reported of engine gas generator
speed (Ng) rollbacks below idle on engines equipped with an affected
part.

The investigation determined that, during these events, the engine
control lever (ECL) was set to idle, and identified as contributing
factors specific environmental temperatures, possibly in combination
with a high power off-take. The idle setting may be used in flight, in
particular during the approach phase.

This condition, if not detected and corrected, may lead to loss of
engine power and eventually, on a single engine aeroplane, possibly
result in loss of control.

To address this potential unsafe condition, GEAC issued the ASB
providing applicable instructions.

For the reason described above, this [EASA] AD requires, for
engines installed on single-engine aircraft, repetitive functional
checks of the affected part and, eventually, replacement with
serviceable part.

You may obtain further information by examining the MCAI in the AD
docket at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0316.

FAA's Determination

This product has been approved by EASA and is approved for
operation in the United States. Pursuant to our bilateral agreement
with the European Community, EASA has notified the FAA of the unsafe
condition described in the MCAI and service information. The FAA is
issuing this NPRM because the agency evaluated all the relevant
information provided by EASA and determined the unsafe condition
described previously is likely to exist or develop in other products of
the same type design.

Related Service Information Under 1 CFR Part 51

The FAA reviewed GE Aviation Czech Alert Service Bulletin (ASB) No.
ASB-H80-73-00-00-0052[00]/ASB-H75-73-00-00-0022[00] (single document),
Revision 00, dated February 6, 2020. This service information specifies
procedures for performing a functional inspection of the FCU, part
number (P/N) LUN 6590.07-8, and replacing the FCU. 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.

Proposed AD Requirements in This NPRM

This proposed AD would require a functional inspection of the FCU,
P/N LUN 6590.07-8, and, if deficiencies are detected, replacement of
the FCU with a part eligible for installation. This proposed AD would
also require removal and replacement of the FCU, P/N LUN 6590.07-8,
during the next engine overhaul or within 44 months, whichever occurs
first after the effective date of this AD.

Differences Between This Proposed AD and the Service Information or
MCAI

The requirement in EASA AD 2020-0082, dated April 1, 2020, to
perform a functional inspection and if applicable, corrective action,
is limited to GEAC H75-200, H80-100, and H80-200 model turboprop
engines installed on single engine airplanes. This proposed AD does not
base compliance on the type of airplane on which the affected engines
are installed. In addition, paragraph (g)(2) of this proposed AD
requires operators to perform steps 1 through 7 of paragraph 2.1.1 in
the ASB while the ASB specifies doing steps 1 through 8. The FAA
confirmed with the manufacturer that the reference to step 8 in the ASB
is an error.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 33 engines installed on airplanes of U.S. registry.

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

Estimated Costs

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

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 adding the following new airworthiness
directive: