[Federal Register Volume 86, Number 171 (Wednesday, September 8, 2021)]
[Rules and Regulations]
[Pages 50219-50222]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-19243]


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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; Amendment 
39-21698; AD 2021-17-15]
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 
Leonardo S.p.a. Model AB139 and AW139 helicopters with certain main 
rotor blades installed. This AD was prompted by a report of an in-
flight loss of a main rotor blade (MRB) tip cap. This AD requires 
inspecting the MRB tip cap for disbonding. The FAA is issuing this AD 
to address the unsafe condition on these products.

DATES: This AD is effective October 13, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of October 13, 
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://customerportal.leonardocompany.com/en-US/. 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 information on the availability of this material at the FAA, 
call (817) 222-5110. It is also available at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0463.

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 final rule, the 
European Aviation Safety Agency (now European Union Aviation Safety 
Agency) (EASA) AD, any comments received, and other information. The 
street address for

[[Page 50220]]

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: 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:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to Leonardo S.p.a. Model 
AB139 and AW139 helicopters with an MRB that has less than 1,200 total 
hours time-in-service (TIS) and has part number (P/N) 3G6210A00131 with 
any serial number (S/N) listed in Table 1 of Leonardo Helicopters Alert 
Service Bulletin No. 139-520, dated April 26, 2018 (ASB 139-520), 
installed. The NPRM published in the Federal Register on June 16, 2021 
(86 FR 31992). In the NPRM, the FAA proposed to require, within 50 
hours TIS, tap inspecting each MRB tip cap for disbonding using a tap 
hammer or equivalent. If there is no disbonding, the NPRM proposed to 
require tap inspecting the MRB tip cap at intervals not to exceed 50 
hours TIS. If there is any disbonding that does not exceed the 
specified limits in ASB 139-520, the NPRM proposed to require tap 
inspecting the MRB at intervals not to exceed 10 hours TIS. If there is 
any disbonding that exceeds the specified limits in ASB 139-520, the 
NPRM proposed to require removing the MRB from service before further 
flight. The NPRM also specified that 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. Finally, the NPRM proposed to 
prohibit installing any MRB that is identified in the applicability 
section of this AD on any helicopter.
    The NPRM was prompted by reports of incorrect bonding procedures on 
certain MRBs, 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.
    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 
S.p.a.) Model AB139 and AW139 helicopters with MRB P/N 3G6210A00131 
with an 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 flight hours (FH) and replacing the 
affected MRBs within 10 FH 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.
    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 S.p.a. Model 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 FH: 
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 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 ASB 139-520.

Discussion of Final Airworthiness Directive

    The FAA received no comments on the NPRM or on the determination of 
the costs.

Conclusion

    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 reviewed the relevant 
data and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these helicopters.

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.

Differences Between This 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 S/N, as a terminating action for the 
repetitive inspections specified in that AD, whereas this AD does not.

[[Page 50221]]

Costs of Compliance

    The FAA estimates that this AD affects 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 AD.
    Tap inspecting an MRB tip cap takes 1 work-hour, for a cost per 
helicopter of $85 per inspection cycle for a total U.S. fleet cost of 
$9,690 per inspection cycle. Replacing 1 MRB, if required, takes 4 
work-hours, and required parts 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 the manufacturer, however, some of the costs of this 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 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.

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

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:

2021-17-15 Leonardo S.p.a.: Amendment 39-21698; Docket No. FAA-2021-
0463; Project Identifier 2018-SW-050-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective October 13, 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) 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.

(j) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Leonardo Helicopters Alert Service Bulletin No. 139-520, 
dated April 26, 2018.
    (ii) [Reserved]
    (3) 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/.

[[Page 50222]]

    (4) 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.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: fr.inspection@nara.gov, or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on August 13, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-19243 Filed 9-7-21; 8:45 am]
BILLING CODE 4910-13-P


