DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0570; Product Identifier 2019-SW-121-AD]
Airworthiness Directives; Airbus Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to supersede Airworthiness Directive
2018-26-02 for Airbus Helicopters (previously Eurocopter France) Model
AS350B3, EC130B4, and EC130T2 helicopters. AD 2018-26-02 requires
inspecting the pilot's and co-pilot's throttle twist for proper
operation. Since the FAA issued AD 2018-26-02, the FAA received a
public comment that prompted additional review. This proposed AD would
retain the requirements of AD 2018-26-02 and add calendar time
compliance times for the required actions. The actions of this proposed
AD are intended to address an unsafe condition on these products.
DATES: The FAA must receive comments on this proposed AD by July
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow
online instructions for sending your comments electronically.
Mail: Send comments to the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590-0001.
Hand Delivery: Deliver to the "Mail" address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2020-0570;
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 proposed AD, the European Aviation Safety Agency (now European
Union Aviation Safety Agency) (EASA) AD, any comments received, and
other information. The street address for Docket Operations is listed
above. Comments will be available in the AD docket shortly after
For service information identified in this proposed rule, contact
Airbus Helicopters, 2701 N Forum Drive, Grand Prairie, TX 75052;
telephone 972-641-0000 or 800-232-0323; fax 972-641-3775; or at https://
www.airbus.com/helicopters/services/technical-support.html. You may
the view this referenced service information at the FAA, Office of the
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321,
Fort Worth, TX 76177.
FOR FURTHER INFORMATION CONTACT: George Schwab, Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-5110;
The FAA invites you to participate in this rulemaking by submitting
written comments, data, or views. The FAA also invites comments
relating to the economic, environmental, energy, or federalism impacts
that might result from adopting the proposals in this document. The
most helpful comments reference a specific portion of the proposal,
explain the reason for any recommended change, and include supporting
data. To ensure the docket does not contain duplicate comments,
commenters should send only one copy of written comments, or if
comments are filed electronically, commenters should submit only one
The FAA will file in the docket all comments received, as well as a
report summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this proposal,
the FAA will consider all comments received on or before the closing
date for comments. The FAA will consider comments filed after the
comment period has closed if it is possible to do so without incurring
expense or delay. The FAA may change this proposal in light of the
The FAA issued AD 2018-26-02, Amendment 39-19532 (83 FR 66093,
December 26, 2018) ("AD 2018-26-02") for Airbus Helicopters Model
AS350B3 and EC130B4 helicopters with an ARRIEL 2B1 engine with the two-
channel Full Authority Digital Engine Control (FADEC) and with new
twist grip modification (MOD) 073254 (for Model AS350B3 helicopters) or
MOD 073773 (for Model EC130B4 helicopters) installed, and Model AS350B3
and EC130T2 helicopters with an ARRIEL 2D engine installed. AD 2018-26-
02 requires repetitively inspecting the wiring, performing an
insulation test, inspecting the pilot and copilot throttle twist grip
controls, and testing the pilot and copilot throttle twist grip
controls for proper functioning.
AD 2018-26-02 was prompted by EASA AD No. 2017-0059, dated April 6,
2017 (EASA AD 2017-0059), issued by EASA, which is the Technical Agent
for the Member States of the European Union. EASA advised that the
switches in the engine "IDLE" or "FLIGHT" control system could be
affected by the corrosive effects of a salt-laden atmosphere, which
could lead to engine power loss. EASA advised that this condition, if
not detected and corrected, could, in case of failure of the other
switch, prevent the pilot from switching from "IDLE" to "FLIGHT"
mode during training of autorotation landing, making aborting the
autorotation impossible, resulting in unintended touchdown.
Actions Since AD 2018-26-02 Was Issued
Since the FAA issued AD 2018-26-02, the FAA received comments from
one commenter. The commenter requested the FAA clarify why the
compliance time for the repetitive inspections required in AD 2018-26-
02 is given in terms of hours time-in-service (TIS) without also
requiring calendar compliance times. The commenter stated that a lot of
operators do not operate their aircraft 660 hours TIS in a year and
asked whether the FAA is concerned with calendar time. The FAA agrees.
Since the unsafe condition involves corrosion, which has a direct
relationship between calendar time and airworthiness, it is necessary
to add calendar time compliance times for all required actions
including the repetitive inspections in this proposed AD.
These helicopters have been approved by EASA and are approved for
operation in the United States. Pursuant to the FAA's bilateral
agreement with the European Union, EASA has notified the FAA about the
unsafe condition described in its AD. The FAA is proposing this AD
after evaluating all known relevant information and determining that an
unsafe condition is likely to exist or develop on other helicopters of
the same type design.
Related Service Information Under 1 CFR Part 51
The FAA reviewed one document that co-publishes three Airbus
Helicopters Emergency Alert Service Bulletin (EASB) identification
numbers: No. 05.00.61, Revision 3, dated June 15, 2015, for Model
AS350B3 helicopters; No. 05.00.41, Revision 2, dated June 15, 2015, for
the non-FAA type certificated Model AS550C3 helicopter; and No. 05A009,
Revision 3, dated June 15, 2015, for Model EC130B4 helicopters. EASB
Nos. 05.00.61 and 05A009 are incorporated by reference in AD 2018-26-02
and are retained for the requirements of this AD. EASB No. 05.00.41 is
not incorporated by reference in AD 2018-26-02 and is not incorporated
by reference in this AD. This service information applies to
helicopters with an ARRIEL 2B1 engine installed and describes
procedures for a functional check and installation of protection for
micro-contacts (microswitches) 53Ka, 53Kb, and 65K (IDLE/FLIGHT mode).
The FAA also reviewed one document that co-publishes three Airbus
Helicopters EASB identification numbers: No. 05.00.77, Revision 1,
dated June 15, 2015, for Model AS350B3 helicopters; No. 05.00.52,
Revision 1, dated June 15, 2015, for the non-FAA type certificated
Model AS550C3 helicopter; and No. 05A014, Revision 1, dated June 15,
2015, for Model EC130T2 helicopters. EASB Nos. 05.00.77 and 05A014 are
incorporated by reference in AD 2018-26-02 and are retained for the
requirements of this AD. EASB No. 05.00.52 is not incorporated by
reference in this AD. This service information applies to helicopters
with an ARRIEL 2D engine installed and describes procedures for a check
of the protection for micro-contacts (microswitches) 53Ka, 53Kb, and
65K (IDLE/FLIGHT mode).
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
This proposed AD would retain the inspection requirements of AD
2018-26-02 and would include, before the next practice autorotation,
within 100 hours TIS, or 6 months, whichever occurs first, inspecting
the wiring, performing an insulation test, inspecting the pilot and
copilot throttle twist grip controls, and testing the pilot and copilot
throttle twist grip controls for proper functioning. This AD would also
include calendar time requirements for the repetitive inspections to be
completed at intervals not to exceed 330 hours TIS or 6 months,
whichever occurs first, and at intervals not to exceed 660 hours TIS or
12 months, whichever occurs first, depending on operating conditions.
Differences Between This Proposed AD and the EASA AD
The EASA AD requires the initial inspections within 10 flight hours
or 7 days; this proposed AD requires compliance before the next
autorotation training flight, 100 hours TIS, or 6 months, whichever
occurs earlier, as the unsafe condition only occurs when transitioning
the throttle in-flight from flight to idle and back to flight, such as
during a practice autorotation.
Additionally, the EASA AD requires installing Airbus Helicopters
MOD 074263; this proposed AD does not as it does not correct the unsafe
The FAA considers this proposed AD to be an interim action. If
final action is later identified, the FAA might consider further
Costs of Compliance
The FAA estimates that this proposed AD would affect 617
helicopters of U.S. Registry. The FAA estimates that operators may
incur the following costs in order to comply with this proposed AD.
Labor costs are estimated at $85 per work-hour.
Inspecting the wiring, performing an insulation test, inspecting
the pilot and copilot throttle twist grip controls, and testing the
pilot and copilot throttle twist grip controls would take about 4 work-
hours, for a total estimated cost of $340 per helicopter and $209,780
for the U.S. fleet per inspection cycle.
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, I certify this proposed regulation:
1. Is not a "significant regulatory action" under Executive Order
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
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 removing Airworthiness Directive (AD)
2018-26-02, Amendment 39-19532 (83 FR 66093, December 26, 2018), and
adding the following new AD: