Document ID: FAA-2020-0907-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Airbus Helicopters
Posted Date: 2020-10-15T04:00Z

[Federal Register Volume 85, Number 200 (Thursday, October 15, 2020)]
[Proposed Rules]
[Pages 65285-65288]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-22744]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0907; Product Identifier 2017-SW-072-AD]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters

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 Airbus Helicopters Model AS350B3 helicopters. This proposed AD 
would require modifying the electrical system of the throttle twist 
grip, inspecting the routing of a microswitch electrical harness, and 
correcting the electrical harness routing if it is incorrect. This 
proposed AD was prompted by reports of the engine remaining in idle 
when the twist grip was turned from the ``forced idle'' position to the 
``flight'' position. 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 November 
30, 2020.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     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-
0907; or in person at Docket Operations

[[Page 65286]]

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 receipt.
    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 view the 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.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to participate in this rulemaking by submitting 
written comments, data, or views. 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 time.
    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 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 comments received.

Confidential Business Information

    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 George Schwab, Aviation Safety Engineer, Safety 
Management Section, Rotorcraft Standards Branch, FAA, 10101 Hillwood 
Pkwy., Fort Worth, TX 76177; telephone 817-222-5110. Any commentary 
that the FAA receives which is not specifically designated as CBI will 
be placed in the public docket for this rulemaking.

Discussion

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued a series of ADs, most recently EASA AD No. 
2017-0035, dated February 20, 2017 (EASA AD 2017-0035), to correct an 
unsafe condition for Airbus Helicopters (formerly Eurocopter) Model AS 
350 B3 helicopters with ARRIEL 2B engines installed. EASA advises of an 
initial report of the microswitch pin jammed in the pushed-in position 
resulting in the engine remaining in idle when the twist grip had been 
turned back to the ``flight'' position during an autorotation training 
exercise. This condition could also occur during governor failure 
training when the twist grip is turned in the low flow rate direction. 
EASA also advises of two later reports of this condition, with one of 
those reports related to an incorrectly routed electrical harness. EASA 
advises that this condition, if not detected and corrected, could lead 
to reduced control of the helicopter.
    EASA initially issued AD No. 2006-0094, dated April 21, 2006, which 
required repetitive testing of the microswitch and established a life 
limit for the microswitch. Subsequent EASA AD action required reducing 
that life limit, inspecting the travel of the collective lever, 
performing an additional check of the collective lever for free travel, 
and installing a terminating action modification that was available for 
certain helicopter configurations. That modification gave priority to 
the HydroMechanical Unit (HMU) flight position when the microswitch 
failed to operate correctly at forced idle. EASA most recently issued 
AD 2017-0035, which prompted this AD action, to include all of the 
previous AD requirements and expand the terminating action modification 
to other helicopter configurations.

FAA's Determination

    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 of the 
unsafe condition described in its AD. The FAA is proposing this AD 
because the FAA evaluated all known relevant information and determined 
that an unsafe condition is likely to exist or develop on other 
products of the same type designs.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Airbus Helicopters Alert Service Bulletin (ASB) 
No. AS350-67.00.43, Revision 3, dated June 16, 2016, which specifies 
procedures, based on different configurations, to modify the electrical 
operation to give priority to the HMU flight position when the 
microswitch does not operate correctly at forced idle (corresponds to 
Airbus Helicopters Modification (MOD) 073357). This service information 
also specifies instructions to inspect the routing of microswitch 
electrical harness number ``53K''.
    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.

Other Related Service Information

    The FAA also reviewed Eurocopter ASB No. 05.00.49, Revision 3, 
dated March 8, 2012. This service information specifies procedures, for 
helicopters without MOD 073357 installed, for repetitive testing of the 
microswitch, a life limit for the microswitch, inspecting the travel of 
the collective lever, and verifying correct wiring harness 
installation.

Proposed AD Requirements

    This proposed AD would require, based on helicopter configuration, 
modifying the electrical system of the throttle twist grip. This 
proposed AD would also require inspecting the routing of a microswitch 
electrical harness, and depending on the routing of that electrical 
harness, correcting the routing.

[[Page 65287]]

Differences Between This Proposed AD and the EASA AD

    The EASA AD specifies a repetitive test of the microswitch, a life 
limit for the microswitch, and inspecting the travel of the collective 
lever, until the terminating action of modifying the electrical system 
of the throttle twist grip and inspecting the routing of a microswitch 
electrical harness are completed. This proposed AD would only require 
modifying the electrical system of the throttle twist grip and 
inspecting the routing of a microswitch electrical harness. The EASA AD 
specifies performing that terminating action in a compliance time of 
calendar months. This proposed AD would require performing the required 
actions before the next practice autorotation, before the next 
simulated governor failure, or within 330 hours time-in-service, 
whichever occurs first.

Costs of Compliance

    The FAA estimates that this proposed AD would affect 517 
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.
    Modifying the electrical system and inspecting the electrical 
harness routing would take about 30 work-hours and parts would cost 
about $9,692 for an estimated cost of $12,242 per helicopter and 
$6,329,114 for the U.S. fleet.

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, I certify this proposed regulation:
    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 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

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 (AD):

Airbus Helicopters: Docket No. FAA-2020-0907; Product Identifier 
2017-SW-072-AD.

(a) Applicability

    This AD applies to Airbus Helicopters Model AS350B3 helicopters, 
certificated in any category, with a Turbomeca ARRIEL 2B engine 
installed.

(b) Unsafe Condition

    This AD defines the unsafe condition as failure of the 
electrical operation of the throttle twist grip, which can prevent 
switching from ``IDLE'' mode to ``FLIGHT'' mode. During autorotation 
training or during governor failure training (when the throttle grip 
is turned in the low flow direction), this condition prohibits 
recovery from a practice autorotation and compels the pilot to 
continue the autorotation to the ground. This condition could result 
in unintended touchdown to the ground at a flight-idle power 
setting, damage to the helicopter, and injury to occupants.

(c) Comments Due Date

    The FAA must receive comments by November 30, 2020.

(d) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(e) Required Actions

    Before the next practice autorotation, before the next simulated 
governor failure, or within 330 hours time-in-service, whichever 
occurs first, modify the electrical operation of the throttle twist 
grip to give priority to the HydroMechanical Unit flight position 
when the microswitch does not operate correctly at forced idle 
(corresponds to Airbus Helicopters Modification (MOD) 073357) as 
follows:
    (1) For helicopters without MOD 073087 and without MOD 073135 
installed:
    (i) Install box ``69K'' on the Full Authority Digital Engine 
Control plate, relay ``81K'' on frame X1310, install fuses on the 
console end comprising circuit-breaker panels ``31 ALPHA'' and ``32 
ALPHA,'' and modify the electrical wiring by following the 
Accomplishment Instructions, paragraph 3.B.2.a. of Airbus 
Helicopters Alert Service Bulletin No. AS350-67.00.43, Revision 3, 
dated June 16, 2016 (ASB AS350-67.00.43), except you are not 
required to discard parts.
    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following paragraph 3.B.2.e. of 
ASB AS350-67.00.43. If the wiring routing is incorrect, before 
further flight, correct the wiring routing by following paragraph 
3.B.2.f. of ASB AS350-67.00.43.
    (2) For helicopters with MOD 073087 (series) and without MOD 
073135 installed:
    (i) Install relays ``54K'' and ``81K'' on frame X1310 and modify 
the electrical wiring by following paragraph 3.B.2.b. of ASB AS350-
67.00.43.
    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following paragraph 3.B.2.e. of 
ASB AS350-67.00.43. If the wiring routing is incorrect, before 
further flight, correct the wiring routing by following paragraph 
3.B.2.f. of ASB AS350-67.00.43.
    (3) For helicopters with MOD 073087 (retrofit) and without MOD 
073135 installed:
    (i) Install relay ``81K'' on frame X1310 and modify the 
electrical wiring by following paragraph 3.B.2.c. of ASB AS350-
67.00.43.
    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following paragraph 3.B.2.e. of 
ASB AS350-67.00.43. If the wiring routing is incorrect, before 
further flight, correct the wiring routing by following paragraph 
3.B.2.f. of ASB AS350-67.00.43.
    (4) For helicopters with MOD 073087 and with MOD 073135 
installed:
    (i) Install relay ``81K'' on frame X1310 and modify the 
electrical wiring by following paragraph 3.B.2.d. of ASB AS350-
67.00.43.
    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following paragraph 3.B.2.e. of 
ASB AS350-67.00.43. If the wiring routing is incorrect, before 
further flight, correct the wiring routing by following paragraph 
3.B.2.f. of ASB AS350-67.00.43.
    (5) For helicopters with MOD 073084 and with MOD 073222 
installed:
    (i) Install relay ``81K'' on frame X1310 and modify the 
electrical wiring by following paragraph 3.B.2.g. of ASB AS350-
67.00.43, except you are not required to scrap parts.

[[Page 65288]]

    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following paragraph 3.B.2.e. of 
ASB AS350-67.00.43. If the wiring routing is incorrect, before 
further flight, correct the wiring routing by following paragraph 
3.B.2.f. of ASB AS350-67.00.43.
    (6) For helicopters with optional Autopilot ``81K'' and without 
MOD 073222 installed:
    (i) Position relay ``81K'' on frame X1310 by following paragraph 
3.B.2.h. of ASB AS350-67.00.43.
    (ii) Inspect the routing of microswitch electrical harness 
``53K'' for correct installation by following ASB AS350-67.00.43, 
step 3.B.2.e. If the wiring routing is incorrect, before further 
flight, correct the wiring routing by following paragraph 3.B.2.f. 
of ASB AS350-67.00.43.

(f) Special Flight Permits

    Special flight permits are prohibited.

 (g) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Rotorcraft Standards Branch, FAA, may approve 
AMOCs for this AD. Send your proposal to: George Schwab, Aviation 
Safety Engineer, Safety Management Section, Rotorcraft Standards 
Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 
817-222-5110; email 9-ASW-FTW-AMOC-Requests@faa.gov.
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, the FAA suggests 
that you notify your principal inspector, or lacking a principal 
inspector, the manager of the local flight standards district office 
or certificate holding district office before operating any aircraft 
complying with this AD through an AMOC.

 (h) Additional Information

    (1) Eurocopter Alert Service Bulletin No. 05.00.49, Revision 3, 
dated March 8, 2012, which is not incorporated by reference, 
contains additional information about the subject of this AD. For 
service information identified in this AD, 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 
view the referenced service information at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-
321, Fort Worth, TX 76177.
    (2) The subject of this AD is addressed in European Aviation 
Safety Agency (now European Union Aviation Safety Agency) (EASA) AD 
No. 2017-0035, dated February 20, 2017. You may view the EASA AD on 
the internet at https://www.regulations.gov in the AD Docket.

 (i) Subject

    Joint Aircraft Service Component (JASC) Code: 7697, Engine 
Control System Wiring.

    Issued on October 6, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-22744 Filed 10-14-20; 8:45 am]
BILLING CODE 4910-13-P