DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0503; Product Identifier 2018-SW-006-AD; Amendment
39-21386; AD 2021-02-03]
RIN 2120-AA64
Airworthiness Directives; Leonardo S.p.a. Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD)
for
certain Leonardo S.p.a. (Leonardo) Model AW189 helicopters. This AD
requires various repetitive inspections of the
main rotor (MR) damper. This AD was prompted by reports of in-service
MR damper failures and the development of an improved MR damper. This
condition, if not corrected, could lead to loss of the lead-lag damping
function of the MR blade, possibly resulting in damage to adjacent
critical rotor components and subsequent loss control of the
helicopter. The actions of this AD are intended to address the unsafe
condition on these products.
DATES: This AD is effective April 1, 2021.
The Director of the Federal Register approved the incorporation by
reference of certain documents listed in this AD as of April 1, 2021.
ADDRESSES: For service information identified in this final rule
contact Leonardo S.p.A. Helicopters, Emanuele Bufano, Head of
Airworthiness, Viale G.Agusta 520, 21017 C.Costa di Samarate (Va)
Italy; telephone +39-0331-225074; fax +39-0331-229046; or at https://www.leonardocompany.com/en/home.
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. It is
also available on the internet at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0503.
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-
0503; 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 AD, the European Aviation Safety Agency (now European Union
Aviation Safety Agency) (EASA) AD, any service information that is
incorporated by reference, any comments received, and other
information. The street address for Docket Operations is U.S.
Department of Transportation, Docket Operations, M-30, West Building
Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC
20590.
FOR FURTHER INFORMATION CONTACT: Matt Fuller, AD Program Manager,
Operational Safety Branch, Airworthiness Products Section, General
Aviation & Rotorcraft Unit, FAA, 10101 Hillwood Pkwy., Fort Worth, TX
76177; telephone 817-222-5110; email matthew.fuller@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to Leonardo Model AW189
helicopters with MR damper part number (P/N) 4F6220V00251 installed.
The NPRM published in the Federal Register on May 20, 2020 (85 FR
30664). The NPRM proposed to require reducing the installation torque
of the nuts on the bolts attaching the MR damper to the MR hub. The
NPRM also proposed to require, at specified intervals, replacing the
affected MR damper; dye penetrant or eddy current inspecting the rod
end and body end of each MR damper for a crack, visually inspecting the
rod end and body end of each MR damper for a crack, and replacing any
cracked MR damper. For certain helicopters, the NPRM also proposed to
require inspecting each rod end and body end bearing for rotation, and
replacing the rod end or MR damper as applicable if there is any
rotation; inspecting the lag damper broached ring nut for damage,
correct engagement, and alignment and removing the rod end and broached
ring nut from service if any of those conditions exist. For all
helicopters, the NPRM proposed to require, at specified intervals,
inspecting the bearing friction torque of each MR damper body end and
rod end, and replacing the MR damper if the torque value exceeds 30.0
Nm (265.5 lb in); inspecting the MR damper anti-rotation block for wear
and replacing the anti-rotation block if there is wear beyond
acceptable limits; and replacing each special washer P/N 3G6220A05051
with special washer P/N 3G6220A05052. For certain MR dampers, the NPRM
proposed to require inspecting the broached ring for damage and
alignment, removing the broached ring from service if there is damage,
and replacing the broached ring if the rod end and broached ring cannot
be aligned. Finally, the NPRM proposed to require inspecting certain
serial-numbered MR dampers for correct torque of the broached ring
prior to installation on any helicopter. The proposed requirements were
intended to detect a crack in an MR damper, which if not detected and
corrected, could lead to loss of the lead-lag damping function of the
MR blade, resulting in damage of the MR damper, detachment of the MR
damper in-flight, and subsequent loss of control of the helicopter.
The NRPM was prompted by EASA AD No. 2016-0145R1, dated January 17,
2018 (EASA AD 2016-0145R1), issued by EASA, which is the Technical
Agent for the Member States of the European Union, to correct an unsafe
condition for Leonardo Model AW189 helicopters with MR damper P/N
4F6220V00251 installed. EASA advises that a MR damper failed, which
resulted in complete seizure of the body end lug and an in-flight
disconnection of the damper. EASA states that a combination of factors
may have contributed to the MR damper disconnection, and that this
condition could result in loss of the lead-lag damping function of the
MR blade, damage to adjacent critical rotor components, and subsequent
reduced control of the helicopter. The contributing factors include
cracks, slippage marks, damaged broach ring teeth, and loss of torque.
According to EASA, the AW189 MR damper is a similar design to the
MR dampers installed on Model AW139 helicopters, where multiple MR
damper failures have been reported involving the body end lug, the eye
end lug, and the rod end. To correct this condition, EASA issued a
series of superseded and revised ADs to require repetitive inspections
of certain MR dampers, and similar corrective actions as those for
Model AW139 helicopters. EASA AD 2016-0145R1 requires various one-time
and repetitive inspections of the MR damper, a torque check of the body
end, and replacing any MR damper with a crack or that fails the torque
check. EASA AD 2016-0145R1 also allows installation of a new MR damper,
P/N 8G6220V00151, as an optional terminating action for the repetitive
inspections.
Comments
The FAA gave the public the opportunity to participate in
developing this final rule, but the FAA did not receive any comments on
the NPRM or on the determination of the cost to the public.
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 issuing this AD after
evaluating all of the information provided by EASA and determining the
unsafe condition exists and is likely to exist or develop on other
helicopters of the same type design and that air safety and the public
interest require adopting these AD requirements as proposed.
Differences Between This AD and the EASA AD
The EASA AD requires contacting the manufacturer under certain
conditions, while this AD does not.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Finmeccanica Bollettino Tecnico No. 189-080,
Revision A, dated July 15, 2016, which contains procedures for visual
and dye penetrant inspections of the MR damper for cracks and for
verifying the torque of the damper body ends.
The FAA also reviewed Leonardo Helicopters Alert Service Bulletin
No. 189-102, Revision A, dated December 21, 2017, which contains
procedures for installing an MR damper with reduced torque values and
specifies replacing MR damper P/N 4F6220V00251 with new MR damper P/N
8G6220V00151.
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 reviewed Finmeccanica Bollettino Tecnico No. 189-069, dated
February 12, 2016, which contains procedures for installing a special
washer on the MR damper rod end, modifying the installation torque of
the MR damper, and inspecting the rod end bearings.
Costs of Compliance
The FAA estimates that this AD affects 3 helicopters of U.S.
Registry. The FAA estimates that operators may incur the following
costs in order to comply with this AD. Labor costs are estimated at $85
per work-hour.
Adjusting the tightening torque takes about 10 work-hours, for an
estimated cost of $850 per helicopter and $2,550 for the U.S. fleet.
Replacing an MR damper takes about 2 work-hours, and parts cost
about $18,000, for an estimated cost of $18,170 per MR damper.
Performing a dye penetrant or eddy current inspection of the MR
damper takes about 8 work-hours, for an estimated cost of $680 per
helicopter and $2,040 for the U.S fleet.
Visually inspecting the rod ends and body ends takes about 0.5
hour, for an estimated cost of $43 per helicopter and $129 for the U.S.
fleet, per inspection cycle.
Inspecting the rod ends and body ends for bearing rotation takes
about 0.5 hour, for an estimated cost of $43 per helicopter and $129
for the U.S. fleet, per inspection cycle.
Inspecting the broached ring nut takes about 0.5 hour, for an
estimated cost of $43 per helicopter and $129 for the U.S. fleet, per
inspection cycle.
Inspecting for bearing friction takes about 2 hours, for an
estimated cost of $170 per helicopter and $510 for the U.S fleet, per
inspection cycle.
Inspecting the broached ring teeth for proper alignment and
applying torque takes about 8 work-hours, for an estimated cost of $680
per helicopter and $2,040 for the U.S fleet.
Replacing a rod end takes about 3 work-hours and parts cost about
$500, for an estimated cost of $755 per rod end.
Replacing a broached ring takes about 3 work-hours and parts cost
about $100, for an estimated cost of $355 per broached ring.
Replacing a broached ring nut takes about 3 work-hours and parts
cost about $125, for an estimated cost of $380 per broached ring nut.
Replacing an anti-rotation block takes about 3 work-hours and parts
cost about $50, for an estimated cost of $305 per anti-rotation block.
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 helicopters identified in this rulemaking action.
Regulatory Findings
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 above, I certify that this AD:
(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.
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:
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