DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-1180; Project Identifier MCAI-2020-00517-E]
Airworthiness Directives; Safran Helicopter Engines, S.A. (Type
Certificate Previously Held by Turbomeca, S.A.) Turboshaft Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to adopt a new airworthiness directive
for certain Safran Helicopter Engines, S.A. (Safran Helicopter Engines)
Arriel 2B, 2B1, 2C, 2C1, 2C2, 2S1 and 2S2 model turboshaft engines.
This proposed AD was prompted by reports of non-conforming fuel filter
pre-blockage pressure switches. This proposed AD would require
repetitive visual inspections of the fuel filter by-pass indicator pop-
up, a one-time operational test of the fuel filter pre-blockage
pressure switch and, depending on the findings, replacement of the fuel
filter pre-blockage pressure switch 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 April
ADDRESSES: You may send comments, using the procedures found in
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow
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.
For service information identified in this NPRM, contact Safran
Helicopter Engines, S.A., Avenue du 1er Mai, Tarnos, France; phone: +33
(0) 5 59 74 45 11. 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-2020-1180; 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: Wego Wang, Aviation Safety Engineer,
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone:
(781) 238-7134; fax: (781) 238-7199; email: email@example.com.
The FAA invites you to send any written relevant data, views, or
arguments about this proposal AD. Send your comments to an address
listed under ADDRESSES. Include "Docket No. FAA-2020-1180; Project
Identifier MCAI-2020-00517-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 Wego Wang, 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.
The European Union Aviation Safety Agency (EASA), which is the
Technical Agent for the Member States of the European Community, has
issued EASA AD 2019-0180, dated July 25, 2019 (referred to after this
as "the MCAI"), to address the unsafe condition on these products.
The MCAI states:
Occurrences have been reported of non-conforming fuel filter
pre-blockage pressure switches, manufactured before December 2016.
The non-conformity of the fuel filter pre-blockage pressure switch
can cause its non-activation in case of fuel system contamination,
with consequent opening of the by-pass without indication in the
This condition, if not detected and corrected, and in case of
fuel contamination, could lead to an uncommanded in-flight shut-
down, possibly resulting in an emergency autorotation landing on a
single engine helicopter, or to a double uncommanded in-flight shut-
down on a twin engine helicopter.
To address this potential unsafe condition, SAFRAN issued the
MSB, providing inspection instructions.
For the reasons described above, this [EASA AD] requires
repetitive daily visual checks of the fuel filter by-pass indicator
pop-up. This [EASA] AD also requires a one-time operational check of
the affected part and, depending on findings, replacement of that
part, which constitutes terminating action for the repetitive daily
checks as required by this [EASA] AD.
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-2020-1180.
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 us of the unsafe
condition described in the MCAI and service information referenced
above. The FAA is proposing this AD 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 Task 73-23-01-750-801-A01--Pre-Blockage Pressure
Switch of the Fuel Filter Tests (Electrical), dated November 30, 2012,
from the Turbomeca Arriel 2 S1 Maintenance Manual. Task 73-23-01-750-
801-A01 provides instructions for performing an operational test of the
fuel filter pre-blockage pressure switch. 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
Other Related Service Information
The FAA reviewed Safran Helicopter Engines Mandatory Service
Bulletin (MSB) No. 292 73 2869, Version B, dated December 2018. The MSB
describes procedures for identifying and securing pre-blockage pressure
switches of fuel filter part number P/N 9 550 17 200 0, which are
Proposed AD Requirements in This NPRM
This proposed AD would require repetitive visual inspections of the
fuel filter by-pass indicator pop-up, a one-time operational test of
the fuel filter pre-blockage pressure switch and, depending on the
findings, replacement of the fuel filter pre-blockage pressure switch
with a part eligible for installation.
Justification for Allowing Pilot To Perform Visual Inspection
This proposed AD would allow the visual inspections required by
paragraph (g)(1) of this NPRM to be performed by an aircrew member
holding at least a private pilot certificate. Performing a visual
inspection to determine if the fuel filter by-pass indicator pop-up has
been activated is not considered an action that must be performed by a
certified person under 14 CFR 43.3. This authorization is an exception
to our standard maintenance regulations.
Differences Between This Proposed AD and the MCAI or the Service
EASA AD 2019-0180 defines "Group 1" engines as Safran Helicopter
Engines Arriel 2B, 2B1, 2B1A, 2C, 2C1, 2C2, 2S1 and 2S2 model
turboshaft engines with an affected a fuel filter pre-blockage pressure
switch and "Group 2" engines as the same Safran Helicopter Engines
Arriel turboshaft engines not equipped with an affected fuel filter
pre-blockage pressure switch. This AD does not define or use "Group
1" or "Group 2" and identifies both the affected engines and the
affected fuel filter pre-blockage pressure switch in the Applicability
paragraph. This AD does not include Safran Helicopter Engines Arriel
2B1A model turboshaft engines since these engines are not type
certificated in the United States.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 775 engines installed on helicopters of U.S. registry.
The FAA estimates the following costs to comply with this proposed
||Cost per product
||Cost on U.S. operators
|Visual inspection of fuel filter
||1 work-hour x $85 per hour =
|Operational test of the fuel
filter pre-blockage pressure switch
||3 work-hours x $85 per hour =
The FAA estimates the following costs
to do any necessary
replacement that would be required based on the results of the proposed
inspection. The FAA has no way of determining the number of aircraft
that might need this replacement.
||Cost per product
|Replace fuel filter pre-blockage
||2 work-hours x $85 per hour =
The FAA has included all known costs
in its cost estimate.
According to the manufacturer, however, some of 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.
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
(1) Is not a "significant regulatory action" under Executive
(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
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