DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-5806; Directorate Identifier 2015-SW-083-AD;
Amendment 39-18331; AD 2015-22-53]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Final rule; request for comments.

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SUMMARY: We are publishing a new airworthiness directive (AD) for
Airbus Helicopters Model AS350B3 helicopters. This AD was sent
previously to all known U.S. owners and operators of these helicopters
and supersedes Emergency AD 2015-22-52, dated October 28, 2015. This AD
requires revising the rotorcraft flight manual (RFM) to stop performing
the yaw load compensator check during preflight procedures and instead
perform it during post-flight procedures after rotor shut-down. This AD
also requires the yaw servo hydraulic switch
to be in the ``ON'' position before taking off. This AD is prompted by
two accidents and one incident of Airbus Helicopters Model AS350B3
helicopters. From preliminary investigations, loss of tail rotor (T/R)
control during takeoff was evident in each event. These actions are
intended to prevent takeoff without hydraulic pressure in the T/R
hydraulic system, loss of T/R flight control, and subsequent loss of
control of the helicopter.

DATES: This AD becomes effective December 16, 2015 to all persons
except those persons to whom it was made immediately effective by
Emergency AD 2015-22-53, issued on October 30, 2015, which contains the
requirements of this AD.
We must receive comments on this AD by February 1, 2016.

ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Docket: Go to http://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 http://www.regulations.gov
by searching for and locating Docket No. FAA-2015-
5806; or in person at the Docket Operations Office between 9 a.m. and 5
p.m., Monday through Friday, except Federal holidays. The AD docket
contains this AD, the European Aviation Safety Agency (EASA) AD, the
economic evaluation, any comments received, and other information. The
street address for the Docket Operations Office (telephone 800-647-
5527) is in the ADDRESSES section. Comments will be available in the AD
docket shortly after receipt.
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 http://www.airbushelicopters.com/techpub. You may review 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: Stephen Barbini, Flight Test Engineer,
Regulations and Policy Group, Rotorcraft Directorate, FAA, 10101
Hillwood Pkwy, Fort Worth, TX 76177; telephone (817) 222-5110; email
stephen.barbini@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments prior to it becoming effective. However, we
invite you to participate in this rulemaking by submitting written
comments, data, or views. We also invite comments relating to the
economic, environmental, energy, or federalism impacts that resulted
from adopting this AD. The most helpful comments reference a specific
portion of the AD, 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 them only one time. We will file in the docket all comments that
we receive, as well as a report summarizing each substantive public
contact with FAA personnel concerning this rulemaking during the
comment period. We will consider all the comments we receive and may
conduct additional rulemaking based on those comments.

Discussion

On October 28, 2015 we issued Emergency AD 2015-22-52 for Airbus
Helicopters Model AS350B3 helicopters with a dual hydraulic system that
prohibited performing the yaw load compensator check (collective
switch) during preflight procedures and instead required performing it
during post-flight procedures. Emergency AD 2015-22-52 also required
the yaw servo hydraulic switch (collective switch) to be in the ``ON''
(forward) position before taking off. Emergency AD 2015-22-52 was sent
previously to all known U.S. owners and operators of these helicopters.
The actions in Emergency AD 2015-22-52 were intended to prevent takeoff
without hydraulic pressure in the T/R hydraulic system, loss of T/R
flight control, and subsequent loss of control of the helicopter.
Emergency AD 2015-22-52 was prompted by two accidents and one
incident of Airbus Helicopters Model AS350B3 helicopters with a dual
hydraulic system installed. From preliminary investigations, loss of T/
R control during takeoff was evident in each event. Each event
experienced a counterclockwise rotational yaw immediately after
takeoff. It was also noted that the anti-torque pedals felt jammed or
locked in the neutral position by the pilots in the two non-fatal
events. The conditions in the events are indicative of takeoffs without
hydraulic T/R assistance caused by a lack of pressure in the T/R
hydraulic system. When taking off without T/R hydraulic assistance with
the switch on the collective grip in the ``OFF'' (aft) position, the
yaw load compensator remains discharged and degrades the T/R hydraulic
system, which significantly increases the pilot T/R control load and
prevents sufficient T/R thrust for takeoff.
Based on the accidents and incident, EASA, which is the Technical
Agent for the Member States of the European Union, issued EASA AD No.
2015-0178, dated August 26, 2015, to correct an unsafe condition for
Airbus Helicopters Model AS 350 B3 helicopters, equipped with a dual
hydraulic system identified as modification OP 3082 or OP 3346. EASA
advises of a perceived loss of T/R control that mimics jamming during
take-off if the T/R hydraulic preflight checks are not performed in
accordance with the checklist in the RFM. According to EASA, performing
the T/R hydraulic preflight checks improperly may result in reduced
function of the T/R hydraulic system, thereby significantly increasing
the T/R control load for the pilot.
After we issued Emergency AD 2015-22-52, we received comments
noting an error in terminology and a defect in reporting compliance
that resulted in confusion in how to comply with Emergency AD 2015-22-
52. Specifically, we referred to the collective switch for the yaw load
compensator check, when we should have referred to the ACCU TST switch.
Activating the collective switch after rotor shut-down will have no
effect due to the absence of hydraulic pressure in the system. We also
omitted a method of recording compliance. Therefore, on October 30,
2015, we issued Emergency AD 2015-22-53 to supersede Emergency AD 2015-
22-52 to correct the error in terminology and the defect in recording
compliance. Emergency AD 2015-22-53 requires revising the normal
operating procedures section of the RFM to prohibit performing the yaw
load compensator check (ACCU TST switch) during preflight procedures
and instead require performing it during post-flight procedures after
rotor shut-down. Emergency AD 2015-22-53 also requires revising the RFM
to state that the yaw servo hydraulic switch (collective switch) must be in the
``ON'' (forward) position before taking off. Emergency AD 2015-22-53
was also sent previously to all known U.S. owners and operators of
these helicopters.

FAA's Determination

This helicopter has been approved by the aviation authority of
France and is approved for operation in the United States. Pursuant to
our bilateral agreement with France, EASA, its technical
representative, has notified us of the unsafe condition described in
the EASA AD. We are issuing this AD because we evaluated all
information provided by EASA and determined the unsafe condition exists
and is likely to exist or develop on other helicopters of this same
type design.

Related Service Information

Airbus Helicopters issued Service Bulletin No. AS350-67.00.66,
Revision 1, dated October 22, 2015 (SB AS350-67.00.66), which specifies
inserting specific pages of the bulletin into the RFM. These pages
revise the preflight and post-flight hydraulic checks by moving the T/R
yaw load compensator check from preflight to post-flight. These pages
also revise terminology within the flight manuals for the different
engine configurations.
Airbus Helicopters also issued Safety Information Notice No. 2944-
S-29, Revision 0, dated August 26, 2015 (SIN 2944-S-29), which warns
that attempting to take off without T/R hydraulic assistance (which may
be caused by the yaw servo hydraulic switch on the collective grip in
the ``OFF'' (aft) position) might be incorrectly perceived as T/R
control failure (jam), which could lead to loss of control of the
helicopter if not quickly identified and corrected. SIN 2944-S-29 also
advises of the RFM update that revises the run-up hydraulic check
starting procedures to no longer specify ``pressing'' the yaw servo
hydraulic switch. To mitigate this potential error, the yaw load
compensator check has been moved from preflight to post-flight
procedures. Further, SIN 2944-S-29 states the yaw servo hydraulic
switch, which is located on the collective grip, is also called the
hydraulic pressure switch or hydraulic cut off switch in various RFMs.

AD Requirements

This AD requires, before further flight, revising the RFM to stop
performing the yaw load compensator check (ACCU TST switch) during
preflight procedures and instead perform the yaw load compensator check
during post-flight procedures after rotor shut-down. This AD also
requires revising the RFM to state that the yaw servo hydraulic switch
(collective switch) must be in the ``ON'' (forward) position before
taking off.

Differences Between This AD and the EASA AD

The EASA AD requires revising the RFM by incorporating procedures
contained in Airbus Helicopters Service Bulletin No. AS350-67.00.66,
Revision 0, dated August 26, 2015, and informing all flight crew of the
RFM changes. This AD requires revising the RFM by inserting a copy of
this AD or by making pen and ink changes.

Interim Action

We consider this AD to be an interim action. The design approval
holder is currently developing a terminating action that will address
the unsafe condition identified in this AD. Once this terminating
action is developed, approved, and available, we might consider
additional rulemaking.

Costs of Compliance

We estimate that this AD affects 427 helicopters of U.S. Registry.
We estimate that operators may incur the following costs in order to
comply with this AD at an average labor rate of $85 per work-hour. It
takes about 0.5 work-hour to revise an RFM for a cost of $43 per
helicopter and $18,361 for the U.S. fleet.

FAA's Justification and Determination of the Effective Date

Providing an opportunity for public comments prior to adopting
these AD requirements would delay implementing the safety actions
needed to correct this known unsafe condition. Therefore, we found and
continue to find that the risk to the flying public justifies waiving
notice and comment prior to the adoption of this rule because the
previously described unsafe condition can adversely affect the
controllability of the helicopter and the initial required action must
be accomplished before further flight.
Since it was found that immediate corrective action was required,
notice and opportunity for prior public comment before issuing this AD
were impracticable and contrary to public interest and good cause
existed to make the AD effective immediately by Emergency AD 2015-22-
53, issued on October 30, 2015, to all known U.S. owners and operators
of these helicopters. These conditions still exist and the AD is hereby
published in the Federal Register as an amendment to section 39.13 of
the Federal Aviation Regulations (14 CFR 39.13) to make it effective to
all persons.

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.
We are 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

We determined that 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, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979);
3. Will not affect intrastate aviation in Alaska to the extent that
it justifies making a regulatory distinction; and
4. 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.
We prepared an economic evaluation of the estimated costs to comply
with this AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.

Adoption of 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

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 (AD):