DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0283; Project Identifier 2018-SW-045-AD]
RIN 2120-AA64

Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening
of comment period.

-----------------------------------------------------------------------

SUMMARY: The FAA is revising an earlier proposal for certain Leonardo
S.p.a. Model AB139 and AW139 helicopters. This action revises the
notice of proposed rulemaking (NPRM) by expanding the required actions.
This proposed AD would require various inspections of certain main
rotor (MR) dampers, as specified in a European Aviation Safety Agency
(now European Union Aviation Safety Agency) (EASA) AD, which is
proposed for incorporation by reference (IBR). This proposed AD would
also require reducing the torque of the MR damper hub attachment bolts,
installing a special washer, installing a certain part-numbered MR
damper, and prohibit installing other part-numbered MR dampers. The FAA
is proposing this airworthiness directive (AD) to address the unsafe
condition on these products. Since these actions would impose an
additional burden over those in the NPRM, the FAA is requesting
comments on this SNPRM.

DATES: The comment period for the NPRM published in the Federal
Register on March 31, 2020 (85 FR 17788), is reopened.

The FAA must receive comments on this SNPRM by October 29, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:

Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the
instructions for submitting comments.

Fax: (202) 493-2251.

Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590.

Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For material that is proposed for IBR in this AD, contact the EASA,
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999
000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may
find this material on the EASA website at https://ad.easa.europa.eu.
You may view this material at the FAA, Office of the Regional Counsel,
Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX
76177. For information on the availability of this material at the FAA,
call (817) 222-5110. It is also available in the AD docket on the
internet at https://www.regulations.gov by searching for and locating
Docket No. FAA-2020-0283.

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 SNPRM, 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 FURTHER INFORMATION CONTACT: Matt Fuller, AD Program Manager,
General Aviation & Rotorcraft Unit, Airworthiness Products Section,
Operational Safety Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX
76177; telephone (817) 222-5110; email matthew.fuller@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under ADDRESSES. Include "Docket No. FAA-2020-0283; Project Identifier
2018-SW-045-AD" at the beginning of your comments. The most helpful
comments reference a specific portion of the proposal, explain the
reason for any recommended change, and include supporting data. The FAA
will consider all comments received by the closing date and may amend
this proposal because of those comments.

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 post all comments received, without change, to
https://www.regulations.gov, including any personal information you
provide. The agency will also post a report summarizing each
substantive verbal contact received about this proposal.

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 SNPRM 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 SNPRM, 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 SNPRM. Submissions containing CBI should
be sent to Matt Fuller, AD Program Manager, General Aviation &
Rotorcraft Unit, Airworthiness Products Section, Operational Safety
Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone
(817) 222-5110; email matthew.fuller@faa.gov. Any commentary that the
FAA receives that is not specifically designated as CBI will be placed
in the public docket for this rulemaking.

Background

The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD that
would apply to certain serial-numbered Leonardo S.p.A. Model AB139 and
AW139 helicopters with an MR damper part number (P/N) 3G6220V01351,
3G6220V01352, or 3G6220V01353 installed. The NPRM published in the Federal
Register on March 31, 2020 (85 FR 17788). In the NPRM, the FAA proposed to
require, for an affected helicopter with MR damper P/N 3G6220V01351,
3G6220V01352, or 3G6220V01353 installed, reducing the installation torque
of each hub attachment bolt for each MR damper. For an affected helicopter
with MR damper P/N 3G6220V01351 or 3G6220V01352 installed, the NPRM pro-
posed to require: Repetitively inspecting the MR damper rod end (rod end)
and MR damper body end (body end) for a crack; dye penetrant inspecting or
eddy current inspecting certain rod and body ends for a crack;
repetitively inspecting the rod and body end bearings for rotation in
the damper seat and for misaligned slippage marks; repetitively
inspecting the rod end broached ring nut; and repetitively inspecting
the bearing friction torque value of the body and rod ends, and the MR
damper anti-rotation block. Depending on the results of the various
inspections, the NPRM proposed to require removing a part from service
or replacing a part. For an affected helicopter with MR damper P/N
3G6220V01351 or 3G6220V01352 installed, the NPRM also proposed to
require inspecting each rod end to determine if special washer P/N
3G6220A05052 is installed, and depending on the results, aligning the
rod ends and broached rings, replacing any broached ring that cannot be
aligned, inspecting the broached rings for wear and damage, and
replacing the broached ring and installing a special washer. Lastly,
the NPRM proposed to require installing MR damper P/N 3G220V01353,
prohibit installing MR damper P/N 3G6220V01351 and P/N 3G6220V01352 on
any helicopter, and allow the installation of MR damper P/N 3G220V01353
to constitute terminating action for all of the proposed repetitive
required actions.

The NPRM was prompted by EASA AD 2018-0112R1, dated June 4, 2018
(EASA AD 2018-0112R1), which is the most recent of a series of ADs
issued by EASA, the Technical Agent for the Member States of the
European Union, to correct an unsafe condition for certain 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. EASA advises of multiple failures of MR
damper P/Ns 3G6220V01351 and 3G6220V01352. EASA states that in some
cases these failures occurred at the eye end and body lugs resulting in
disconnection of the MR damper in-flight. EASA further states that a
combination of factors, including cracks on the MR damper rod end and
body end and in-service failure of the eye end and body lugs may have
contributed to the MR damper disconnections. Information issued by
Leonardo Helicopters advises of MR 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 piston slots.

EASA states 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.
Accordingly, EASA AD 2018-0112R1 requires various one-time and
repetitive inspections of the MR damper, a torque check of the damper
body end, and replacing any MR damper with a crack or that fails the
torque check. EASA AD 2018-0112R1 also requires replacing MR damper P/N
3G6220V01351 and 3G6220V01352 with P/N 3G220V01353, as additional tests
determined that MR 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.

Actions Since the NPRM Was Issued

Since the NPRM was issued, the FAA identified an action required by
EASA AD 2018-0112R1 that was inadvertently omitted in the NPRM and
incorrect thresholds for different actions proposed in the NPRM. The
NPRM omitted the one-time dye penetrant inspection for any MR dampers
that have accumulated 300 or more total hours time-in-service (TIS).
The NPRM also stated incorrect thresholds to inspect each rod end
bearing and body end bearing for rotation. The NPRM proposed to require
those inspections based on the total hours TIS accumulated by the MR
damper, when the thresholds for those inspections should have been
based on the total hours TIS accumulated by the rod end and body end,
independently. This SNPRM makes those updates.

The NPRM also inadvertently omitted the option to accomplish an
eddy current inspection for some inspections. This SNPRM adds that
alternative for those inspections.

Lastly, this SNPRM utilizes the FAA's new practice of proposing to
incorporate EASA AD 2018-0112R1 by reference.

Comments

The FAA gave the public the opportunity to participate in
developing this proposed AD. The FAA has considered the comment
received.

Request To Reduce the Applicability

One commenter requested removing MR damper P/N 3G6220V01353 from
the applicability. The commenter stated that the only requirement in
this AD for that P/N is to reduce the torque on the body end of the MR
damper and that procedures for this are available in the Interactive
Electronic Technical Publications (IETP). The commenter asked if the
intent is to capture any MR damper P/N 3G6220V01353 installed prior to
the current IETP revisions with an incorrect torque. The commenter
further stated that part II of Leonardo Helicopters Alert Service
Bulletin No. 139-452, Revision B, dated April 10, 2018 (ASB 139-452 Rev
B), is not applicable to MR damper P/N 3G6220V01353.

The FAA disagrees. The commenter is correct that part II of ASB
139-452 Rev B is not applicable to MR damper P/N 3G6220V01353; however,
part I of ASB 139-452 Rev B, which specifies procedures to reduce the
torque of the nut on the bolt attaching each MR damper to the MR hub,
is applicable to MR damper P/N 3G6220V01353. Additionally, the FAA
appreciates that while the procedures to reduce that torque may now be
available in the IETP, not all operators are required to accomplish
manufacturer's maintenance procedures. Where the FAA has determined
that procedures, including manufacturer's maintenance procedures, are
necessary to correct an unsafe condition, the FAA must issue an AD.

FAA's Determination

These products have been approved by the aviation authority of
another country, and are approved for operation in the United States.
Pursuant to the bilateral agreement with the State of Design Authority,
the FAA has been notified of the unsafe condition described in EASA AD
2018-0112R1 referenced above. The FAA is proposing this AD after
evaluating all the relevant information and determining the unsafe
condition described previously is likely to exist or develop in other
products of these same type designs.

Certain changes described above expand the scope of the NPRM. As a
result, the FAA has determined that it is necessary to reopen the
comment period to provide additional opportunity for the public to
comment on this SNPRM.

Related Service Information Under 1 CFR Part 51

EASA AD 2018-0112R1 requires reducing the installation torque of
the bolts affixing each affected MR damper to the MR hub. For certain
affected MR dampers, EASA AD 2018-0112R1 requires a one-time dye
penetrant inspection of the rod and body ends, and a repetitive
detailed visual inspection of the rod and body ends. EASA AD 2018-
0112R1 allows an eddy current inspection as an alternative to those
inspections. For certain affected MR dampers, EASA AD 2018-0112R1 also
requires repetitively inspecting the rod and body end bearings for
rotation, visually inspecting the rod end broached ring nut,
accomplishing a bearing friction inspection of the body and rod end
bearings, and a detailed inspection of the anti-rotation block. EASA AD
2018-0112R1 also requires a one-time visual inspection of certain
affected MR damper rod end installations and a torque check of the MR
damper broached ring nut. For certain affected MR dampers, EASA AD
2018-0112R1 requires replacing any special washer P/N 3G6220A05051 with
a new washer P/N 3G6220A05052. If there is a crack or damage detected
in any inspection, EASA AD 2018-0112R1 requires contacting Leonardo
and, if the discrepancy is confirmed, replacing the MR damper. EASA AD
2018-0112R1 also requires corrective actions if any discrepancy is
detected in the inspections for rotation, friction, and torque. EASA AD
2018-0112R1 allows installing MR damper P/N 3G6220V01353 on a
helicopter, provided that it is installed using the correct torque
values. Lastly, EASA AD 2018-0112R1 prohibits installing MR damper P/N
3G6220V01351 and P/N 3G6220V01352 on any helicopter.

This material 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 of This SNPRM

This proposed AD would require accomplishing the actions specified
in EASA AD 2018-0112R1, described previously, as incorporated by
reference, except for any differences identified as exceptions in the
regulatory text of this AD and except as discussed under "Differences
Between this Proposed AD and the EASA AD."

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD
process, the FAA developed a process to use some civil aviation
authority (CAA) ADs as the primary source of information for compliance
with requirements for corresponding FAA ADs. The FAA has been
coordinating this process with manufacturers and CAAs. As a result, the
FAA proposes to incorporate EASA AD 2018-0112R1 by reference in the FAA
final rule. This proposed AD would, therefore, require compliance with
EASA AD 2018-0112R1 in its entirety through that incorporation, except
for any differences identified as exceptions in the regulatory text of
this proposed AD. Using common terms that are the same as the heading
of a particular section in EASA AD 2018-0112R1 does not mean that
operators need comply only with that section. For example, where the AD
requirement refers to "all required actions and compliance times,"
compliance with this AD requirement is not limited to the section
titled "Required Action(s) and Compliance Time(s)" in EASA AD 2018-
0112R1. Service information referenced in EASA AD 2018-0112R1 for
compliance will be available at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0283 after the FAA final
rule is published.

Differences Between This Proposed AD and the EASA AD

Where EASA AD 2018-0112R1 requires the compliance time of after the
last flight (ALF) of the day inspection, this proposed AD would require
the compliance time of before the first flight of the day. Some
compliance times in EASA AD 2018-0112R1 are on condition of part
removal or replacement, whereas this proposed AD would not include
those compliance times. EASA AD 2018-0112R1 requires a torque check of
the MR damper broached ring nut, whereas this proposed AD would require
a torque inspection instead to clarify that the action must be
accomplished by a mechanic that meets the requirements of 14 CFR part
65 subpart D. EASA AD 2018-0112R1 requires making sure that there are
no scratches or dents on the rod end, however it does not state
corrective action for this requirement; this proposed AD would require
removing the rod end from service if there is a scratch or dent on the
rod end. Where EASA AD 2018-0112R1 requires contacting Leonardo and
replacing the MR damper with a serviceable part, this proposed would
require replacing or removing parts from service instead. Where EASA AD
2018-0112R1 requires accomplishing applicable corrective action(s) as
specified in, and in accordance with, the instructions in service
information, this proposed AD would require removing parts from service
for some of the corrective actions instead. Where EASA AD 2018-0112R1
requires a one-time dye penetrant inspection of certain rod ends when
installed, this proposed AD would not. Instead, this proposed AD would
prohibit installing certain rod ends that are not marked with a black
dot and therefore have not been inspected.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 126 helicopters of U.S. Registry. Labor rates are estimated at
$85 per work-hour. Based on these numbers, the FAA estimates the
following costs to comply with this proposed AD.

Performing the MR damper inspections would take about 24 work-
hours, for an estimated cost of $2,040 per helicopter and $257,040 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-rotation block. Replacing an MR damper would take
about 2 work-hours and parts would cost about $18,000, for an estimated
cost of $18,170 per MR damper.

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 above, I certify this proposed
regulation:

(1) Is not a "significant regulatory action" under Executive
Order 12866,

(2) Would not affect intrastate aviation in Alaska, and

(3) Would 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

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: