DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0283; Product Identifier 2018-SW-045-AD]
Airworthiness Directives; Leonardo S.p.A. Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to adopt a new airworthiness directive
for certain Leonardo S.p.A. (Leonardo) Model AB139 and AW139
helicopters. This proposed AD would require various inspections of the
main rotor (M/R) damper, and depending on the inspection results,
removing from service or replacing certain parts. This proposed AD
would also require reducing the torque of the M/R damper hub attachment
bolts, marking parts, installing a special washer, and installing a
certain part-numbered M/R damper and prohibit installing other part-
numbered M/R dampers. This proposed AD is prompted by reports of failed
M/R dampers. The proposed actions are intended to address the unsafe
condition on these products.
DATES: The FAA must receive comments on this proposed AD by June
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
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-2020-0283;
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 Union Aviation Safety Agency (previously
European 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
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.
FOR FURTHER INFORMATION CONTACT: Matt Fuller, Senior 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
EASA, which is the Technical Agent for the Member States of the
European Union, has issued a series of superseded and revised ADs to
correct an unsafe condition for Leonardo S.p.A. Helicopters (formerly
Finmeccanica S.p.A., Helicopter Division (FHD), AgustaWestland S.p.A.,
Agusta S.p.A.), AgustaWestland Philadelphia Corporation (formerly
Agusta Aerospace Corporation), Model AB139 and AW139 helicopters, all
serial numbers (S/Ns) except S/Ns 31004, 31007, and 41237. EASA advises
of multiple failures of M/R dampers part number (P/N) 3G6220V01351 and
3G6220V01352. EASA states that in some cases these failures occurred at
the eye end and body lugs resulting in disconnection of the M/R damper
in-flight. EASA further states that a combination of factors, including
cracks on the M/R damper rod end and body end and in-service failure of
the eye end and body lugs may have contributed to the M/R damper
disconnections. Information issued by Leonardo advises of M/R damper
cracking, loose rod ends, bearing rotation in the damper seat, and
damage, incorrect engagement, and misalignment of the lag damper
broached ring nut, particularly the broached ring teeth and the damper
EASA states that this condition could result in loss of the lead-
lag damping function of the M/R blade, damage to adjacent critical
rotor components, and subsequent reduced control of the helicopter.
EASA AD No. 2018-0112R1, dated June 4, 2018 (EASA AD 2018-0112R1),
which is the most recent EASA AD, requires various one-time and
repetitive inspections of the M/R damper, a torque check of the damper
body end, and replacing any M/R damper with a crack or that fails the
torque check. EASA AD 2018-0112R1 also requires replacing M/R damper P/N
3G6220V01351 and 3G6220V01352 with P/N 3G220V01353, as additional
tests determined that M/R damper P/N 3G220V01353 does not need to be
subject to inspections for cracks, provided it is removed from service
before it reaches its retirement life.
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 designs.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Leonardo Helicopters Alert Service Bulletin No.
139-450, Revision C, dated April 10, 2018, which contains procedures
for visual and dye penetrant inspections of the M/R damper for cracks
and for verifying the torque of the M/R damper body ends (body ends).
The FAA also reviewed Leonardo Helicopters Alert Service Bulletin
No. 139-452, Revision B, dated April 10, 2018, which contains
procedures for reducing the body end nut torque.
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 require compliance with certain procedures
described in the manufacturer's service bulletin. Based on the
helicopter's S/N and the M/R damper P/N installed, this proposed AD
would require within 5 hours time-in-service (TIS) and thereafter
before the first flight of each day:
A repetitive visual inspection using a magnifying glass of
the M/R damper rod end (rod end) and body ends for a crack, and
depending on the inspection results, removing the rod end from service
or replacing the M/R damper.
A repetitive inspection of the rod and body end bearings
for rotation in the damper seat and for misaligned slippage marks, and
depending on the inspection results, removing from service the rod end
or replacing the M/R damper.
This proposed AD would also require within 10 hours TIS:
Reducing the installation torque of each hub attachment
bolt for each M/R damper.
This proposed AD would also require within 30 hours TIS, before the
M/R damper accumulates 300 hours TIS, or within 300 hours TIS since
last overhaul, whichever occurs later:
A dye penetrant inspection using a magnifying glass or
eddy current inspection of the rod and body ends for a crack, and
depending on the inspection results, removing from service the rod end
and replacing the M/R damper, or marking the rod and body ends.
This proposed AD would require within 30 hours TIS and thereafter
at intervals not to exceed 20 hours TIS until the M/R damper has
accumulated 600 hours TIS:
A repetitive visual inspection of the rod end broached
ring nut for broken teeth, improper engagement, and misalignment, and
depending on the inspection results, removing from service the broached
This AD would require within 50 hours TIS and thereafter at
intervals not to exceed 100 hours TIS:
A repetitive inspection of the bearing friction torque
value of the body and rod ends, and depending on the inspection
results, removing from service the rod end or replacing the M/R damper.
A repetitive inspection the M/R damper anti-rotation block
(block), and depending on the inspection results, removing the block
This AD would also require, within 50 hours TIS:
If special washer P/N 3G6220A05052 is installed, aligning
the rod ends and broached rings, and replacing any broached ring that
cannot be aligned.
If special washer P/N 3G6220A05052 is not installed,
inspecting the broached rings for wear and damage, and depending on the
inspection results, replacing the broached ring and installing a
This proposed AD would also require installing M/R damper P/N
3G220V01353, prohibit installing M/R damper P/N 3G6220V01351 and P/N
3G6220V01352 on any helicopter, and allow the installation of M/R
damper P/N 3G220V01353 to serve as terminating action for all the
repetitive requirements of this proposed AD.
Differences Between This Proposed AD and the EASA AD
The EASA AD requires contacting the manufacturer under certain
conditions, while this proposed AD would not.
Costs of Compliance
The FAA estimates that this proposed AD would affect 123
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.
Performing the M/R damper inspections would take about 24 work-
hours, for an estimated cost of $2,040 per helicopter and $250,920 for
the U.S. fleet, per inspection cycle.
Replacing a rod end would take about 3 work-hours and parts would
cost about $500, for an estimated cost of $755 per rod end.
Replacing a broached ring and broached ring nut would take about 3
work-hours and parts would cost about $125, for an estimated cost of
$380 per broached ring and broached ring nut.
Replacing an anti-rotation block would take about 3 work-hours and
parts would cost about $50, for an estimated cost of $305 per anti-
Replacing an M/R damper would take about 2 work-hours and parts
would cost about $18,000, for an estimated cost of $18,170 per M/R
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 adding the following new airworthiness