[Federal Register Volume 86, Number 114 (Wednesday, June 16, 2021)]
[Proposed Rules]
[Pages 31992-31994]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-12515]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0463; Project Identifier 2018-SW-050-AD]
RIN 2120-AA64


Airworthiness Directives; Leonardo S.p.a. 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 Leonardo S.p.a. (Leonardo) Model AB139 and AW139 helicopters with 
certain main rotor blades MRB installed. This proposed AD was prompted 
by a report of an in-flight loss of a main rotor blade (MRB) tip cap. 
This proposed AD would require inspecting the MRB tip cap for 
disbonding. The FAA is proposing this AD to address the unsafe 
condition on these products.

DATES: The FAA must receive comments on this proposed AD by August 2, 
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 between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, 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://customerportal.leonardocompany.com/en-US/. You may view this service 
information 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0463 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 NPRM, 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.

FOR FURTHER INFORMATION CONTACT: Bang Nguyen, Aerospace Engineer, 
Certification Section, Fort Worth ACO Branch, Compliance & 
Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 
76177; telephone (817) 222-4973; email bang.nguyen@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-2021-0463; Project Identifier 
2018-SW-050-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 NPRM.

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

[[Page 31993]]

should be sent to Bang Nguyen, Aerospace Engineer, Certification 
Section, Fort Worth ACO Branch, Compliance & Airworthiness Division, 
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-
4973; email bang.nguyen@faa.gov. Any commentary that the FAA receives 
which is not specifically designated as CBI will be placed in the 
public docket for this rulemaking.

Background

    On January 22, 2018, the FAA issued AD 2018-03-01, Amendment 39-
19174 (83 FR 4136, January 30, 2018) (AD 2018-03-01) for Agusta S.p.A. 
(now Leonardo) Model AB139 and AW139 helicopters with MRB part number 
(P/N) 3G6210A00131 with a serial number (S/N) 3615, 3634, 3667, or 3729 
installed. AD 2018-03-01 requires inspecting the MRB tip cap for 
disbonding and was prompted by EASA AD 2017-0175-E, dated September 13, 
2017 (EASA AD 2017-0175-E), issued by EASA, which is the Technical 
Agent for the Member States of the European Union. EASA advised of an 
in-flight loss of an MRB tip cap on an AW139 helicopter where the pilot 
was able to safely land the helicopter. EASA further advised that an 
investigation determined the cause as incorrect bonding procedures used 
during production on MRB P/N 3G6210A00131, S/N 3615, 3634, 3667, and 
3729. According to EASA, this condition could result in loss of an MRB 
tip cap, increased pilot workload, and reduced control of the 
helicopter. To address this unsafe condition, EASA AD 2017-0175-E 
requires a one-time inspection of the affected MRB tip caps within 5 
hours and replacing the affected MRBs within 10 hours if not replaced 
as a result of the inspection. EASA AD 2017-0175-E also prohibits 
installing the affected MRBs on a helicopter. AD 2018-03-01 requires 
the same corrective actions.

Actions Since AD 2018-03-01 Was Issued

    After the FAA issued AD 2018-03-01, EASA issued EASA AD 2018-0130, 
dated June 18, 2018 (EASA AD 2018-0130), to correct the same unsafe 
condition for Leonardo AB139 and AW139 helicopters with additional 
serial-numbered MRBs installed. EASA advises that further 
investigations after EASA AD 2017-0175-E was issued determined that 
another batch of P/N 3G6210A00131 MRBs may have been subject to the 
incorrect bonding procedure, but to a less critical extent. EASA AD 
2018-0130, which neither revises nor supersedes EASA AD 2017-0175-E, 
applies to the following serial-numbered MRBs with less than 1,200 
flight hours: 2709, 3558, 3624, 3707, 3790, 3486, 3561, 3625, 3717, 
3795, 3488, 3569, 3626, 3720, 3798, 3495, 3570, 3627, 3725, 3803, 3500, 
3574, 3628, 3726, 3807, 3501, 3575, 3633, 3734, 3812, 3502, 3582, 3636, 
3735, 3822, 3503, 3583, 3638, 3738, 3824, 3508, 3586, 3642, 3739, 3825, 
3510, 3590, 3648, 3741, 3827, 3513, 3592, 3649, 3743, 3831, 3520, 3595, 
3650, 3744, 3832, 3527, 3597, 3651, 3745, 3838, 3528, 3599, 3657, 3753, 
3841, 3529, 3602, 3665, 3754, 3842, 3531, 3603, 3672, 3761, 3847, 3536, 
3605, 3682, 3766, 3850, 3539, 3609, 3684, 3770, 3851, 3544, 3612, 3686, 
3771, 3852, 3549, 3613, 3690, 3777, 3853, 3551, 3616, 3691, 3783, 3854, 
3556, 3620, 3695, 3788, 3855, 3557, 3622, 3696, and 3789.
    Accordingly, EASA AD 2018-0130 requires within 50 flight hours (FH) 
and thereafter at intervals not to exceed 50 FH, tap inspecting the MRB 
for disbonding. If there is disbonding within permitted limits, EASA AD 
2018-0130 requires tap inspecting the disbonded area within 10 FH and 
thereafter at intervals not to exceed 10 FH. If disbonding that exceeds 
the permitted limits is found during any inspection, EASA AD 2018-0130 
requires replacing the part. EASA AD 2018-0130 also prohibits 
installing the affected part unless it is a serviceable part and 
includes a terminating action for the repetitive inspections, which is 
accumulation of 1,200 FH by an affected part without findings of 
disbonded area, or findings of disbonded area within the limits 
specified in Annex A of Leonardo Helicopters Alert Service Bulletin No. 
139-520, dated April 26, 2018 (ASB 139-520).

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 about the 
unsafe condition described in its AD. The FAA is proposing this AD 
after evaluating all known relevant information and determining that 
the unsafe condition described previously 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 ASB 139-520. This service information specifies 
procedures for repetitively inspecting the tip cap on a certain batch 
of MRBs for disbonding using a tap test and replacing the MRB if 
disbonding is not within permitted limits.
    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 in This NPRM

    This proposed AD would require, for helicopters with affected MRBs 
with less than 1,200 total hours time-in-service (TIS) installed, 
within 50 hours TIS, tap inspecting each MRB tip cap for disbonding 
using a tap hammer or equivalent. If there is no disbonding, tap 
inspecting the MRB tip cap at intervals not to exceed 50 hours TIS 
would be required. If there is any disbonding that does not exceed the 
specified limits in ASB 139-520, tap inspecting the MRB would be 
required at intervals not to exceed 10 hours TIS. If there is any 
disbonding that exceeds the specified limits in ASB 139-520, removing 
the MRB from service would be required before further flight. The 
accumulation of 1,200 total hours TIS on the affected part without 
findings of any disbonded area or with findings of any disbonded area 
that is within the permitted limits in Annex A of ASB 139-520 would 
constitute terminating action for the proposed repetitive inspections. 
This proposed AD would also prohibit installing any MRB that is 
identified in the applicability section on any helicopter.

Differences Between This Proposed AD and the EASA AD

    EASA AD 2018-0130 allows replacing an affected part with a 
serviceable part, which is marked with the letter ``R'' (repaired tip 
cap) as the last digit of the serial number, as a terminating action 
for the repetitive inspections specified in that AD, whereas this 
proposed AD would not.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 114 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.
    Tap inspecting an MRB tip cap would require 1 work-hour, for a cost 
per helicopter of $85 per inspection cycle for a total U.S. fleet cost 
of $9,690. Replacing 1 MRB, if required, would take 4 work-hours, and 
required parts would cost $141,725, for a total cost of $142,065 per 
MRB.
    The FAA has included all known costs in its cost estimate. 
According to

[[Page 31994]]

the manufacturer, however, some of the costs of this proposed AD may be 
covered under warranty, thereby reducing the cost impact on affected 
operators.

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) 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

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:

Leonardo S.p.a.: Docket No. FAA-2021-0463; Project Identifier 2018-
SW-050-AD.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by August 2, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Leonardo S.p.a. Model AB139 and AW139 
helicopters, certificated in any category, with a main rotor blade 
(MRB) that has less than 1,200 total hours time-in-service (TIS) and 
has part number 3G6210A00131 with any serial number listed in Table 
1 of Leonardo Helicopters Alert Service Bulletin No. 139-520, dated 
April 26, 2018 (ASB 139-520), installed.

(d) Subject

    Joint Aircraft Service Component (JASC) Code: 6210, Main Rotor 
Blades.

(e) Unsafe Condition

    This AD was prompted by a report of disbonding of an MRB tip 
cap, which if not detected and corrected, could result in loss of 
the MRB tip cap, severe vibrations, and subsequent loss of control 
of the helicopter.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    (1) Within 50 hours TIS after the effective date of this AD, 
using a tap hammer or equivalent, tap inspect each MRB tip cap for 
disbonding in the area depicted in Figure 1 of ASB 139-520.
    (i) If there is no disbonding, tap inspect each MRB tip cap as 
required by paragraph (g)(1) of this AD at intervals not to exceed 
50 hours TIS.
    (ii) If there is any disbonding that does not exceed the limits 
specified in Annex A, paragraphs 2.3 and 2.4 of ASB 139-520, tap 
inspect the MRB tip cap as required by paragraph (g)(1) of this AD 
at intervals not to exceed 10 hours TIS.
    (iii) If there is any disbonding that exceeds the limits 
specified in Annex A, paragraphs 2.3 and 2.4 of ASB 139-520, remove 
the MRB from service before further flight.
    (2) Accumulation of 1,200 total hours TIS on the affected part 
without findings of any disbonded area or with findings of any 
disbonded area that is within the permitted limits specified in 
Annex A, paragraphs 2.3 and 2.4 of ASB 139-520, constitutes 
terminating action for the repetitive inspections required by 
paragraphs (g)(1)(i) and (ii) of this AD.
    (3) As of effective date of this AD, do not install any MRB that 
is identified in paragraph (c) of this AD on any helicopter.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (i)(1) of 
this AD. Information may be emailed to: 9-AVS-AIR-730-AMOC@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(i) Related Information

    (1) For more information about this AD, contact Bang Nguyen, 
Aerospace Engineer, Certification Section, Fort Worth ACO Branch, 
Compliance & Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort 
Worth, TX 76177; telephone (817) 222-4973; email 
bang.nguyen@faa.gov.
    (2) For service information identified in this AD, 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://customerportal.leonardocompany.com/en-US/. You may view this 
referenced service information 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.
    (3) The subject of this AD is addressed in European Aviation 
Safety Agency (now European Union Aviation Safety Agency (EASA) AD 
2018-0130, dated June 18, 2018. You may view the EASA AD at https://www.regulations.gov in Docket No. FAA-2021-0463.

    Issued on June 9, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-12515 Filed 6-15-21; 8:45 am]
BILLING CODE 4910-13-P


