Airworthiness Directives; Various Restricted Category Helicopters

[Federal Register Volume 85, Number 210 (Thursday, October 29, 2020)]
[Rules and Regulations]
[Pages 68429-68431]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-23929]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0625; Product Identifier 2016-SW-007-AD; Amendment 
39-21315; AD 2020-22-19]
RIN 2120-AA64


Airworthiness Directives; Various Restricted Category 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 
various restricted category helicopters, originally manufactured by 
Sikorsky Aircraft Corporation (Sikorsky), Model EH-60A, HH-60L, S-70, 
S-70A, S-70C, S-70C(M), S-70C(M1), and UH-60A. This AD requires initial 
and recurring inspections of the main rotor (M/R) blade spindle cuff 
for a crack. This AD was prompted by multiple reports of a cracked M/R 
blade spindle cuff. These actions are intended to prevent an unsafe 
condition on these products.

DATES: This AD is effective December 3, 2020.

ADDRESSES: For service information identified in this final rule, 
contact your local Sikorsky Field Representative or Sikorsky's Service 
Engineering Group at Sikorsky Aircraft Corporation, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-946-4337 (1-800-Winged-S); email 
[email protected]. Operators may also log on to the 
Sikorsky 360 website at https://www.sikorsky360.com. 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.

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-
0625; 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, 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: Kristopher Greer, Aerospace Engineer, 
Boston ACO Branch, Compliance and Airworthiness Division, FAA, 1200 
District Avenue, Burlington, Massachusetts 01803; telephone 781-238-
7799; email [email protected].

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 various restricted 
category helicopters, originally manufactured by Sikorsky, Model EH-
60A, HH-60L, S-70, S-70A, S-70C, S-70C(M), S-70C(M1), and UH-60A, with 
an M/R blade spindle cuff part number 70150-09109-041 installed. The 
NPRM published in the Federal Register on July 9, 2020 (85 FR 41221).
    The NPRM was prompted by multiple reports of a cracked M/R blade 
spindle cuff. In 2008, Sikorsky reported an M/R blade spindle cuff on a 
Model UH-60A helicopter that cracked across the lower inboard bolt 
holes. Investigation determined the crack was caused by a non-
conforming hole edge break, specifically a burr, introduced during an 
overhaul at a non-Sikorsky overhaul facility. Sikorsky issued Sikorsky 
Safety Advisory No. SSA-S70-08-002, dated December 11, 2008 (SSA-S70-
08-002), for Black Hawk Model H-60- and S-70-series helicopters to 
inform operators of the incident and recommend compliance with 
Sikorsky's preventative maintenance inspections. The safety advisory 
also recommended that operators with M/R blades

[[Page 68430]]

overhauled by a non-Sikorsky repair facility contact that facility to 
verify whether the hole edge radius requirement was met during the 
overhaul.
    In 2015, the FAA received an additional report of an M/R blade 
spindle cuff on a military model helicopter that cracked. Investigation 
from this reporting has revealed no anomalies at the crack initiation 
site. In each instance, a crack initiated at a bolt hole and spread to 
either an adjacent bolt hole or to the free edge. Due to design 
similarity, Model EH-60A, HH-60L, S-70, S-70A, S-70C, S-70C(M), S-
70C(M1), and UH-60A helicopters are all affected by this unsafe 
condition.
    Accordingly, the NPRM proposed to require initial and recurring 
inspections of the M/R blade spindle cuff for a crack. The proposed 
requirements were intended to detect a crack, prevent failure of an M/R 
blade spindle cuff, loss of an M/R blade, and loss of control of the 
helicopter.

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

    The FAA is issuing this AD after evaluating all known relevant 
information and determining that an unsafe condition exists and is 
likely to exist or develop on other helicopters of these same type 
designs and that air safety and the public interest require adopting 
the AD requirements as proposed.

Related Service Information

    The FAA reviewed SSA-S70-08-002. This service information 
recommends, for helicopters with M/R blades overhauled by non-Sikorsky 
M/R blade repair facilities, contacting the facilities to verify 
whether the hole edge radius requirement was met during cuff 
replacement. The safety advisory also recommends operators conduct 10 
hour/14 day visual inspections and follow the inspection procedures 
regarding sudden onset of low frequency vibration or an out of track 
condition.
    The FAA also reviewed Sikorsky Technical Manual Preventative 
Maintenance Services 10 Hour/14 Day (30 Hour/42 Day) Inspection 
Checklist TM 1-70-PMS-1, dated December 1, 2014, for Sikorsky Model S-
70 helicopters. This service information contains procedures for the 10 
hour/14 day and 30 hour/42 day inspections.

Costs of Compliance

    The FAA estimates that this AD affects 204 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.
    Inspecting the M/R blade spindle cuffs takes about 1 work-hour for 
an estimated cost of $85 per helicopter and $17,340 for the U.S. fleet. 
Replacing an M/R blade spindle cuff takes about 175 work-hours and 
required parts cost about $10,000 for a total estimated replacement 
cost of $24,875 per M/R blade spindle cuff.

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

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:

2020-22-19 Various Restricted Category Helicopters: Amendment 39-
21315; Docket No. FAA-2020-0625; Product Identifier 2016-SW-007-AD.

(a) Applicability

    This airworthiness directive (AD) applies to various restricted 
category helicopters originally manufactured by Sikorsky Aircraft 
Corporation, Model EH-60A, HH-60L, S-70, S-70A, S-70C, S-70C(M), S-
70C(M1), and UH-60A helicopters with a main rotor (M/R) blade 
spindle cuff part number 70150-09109-041 installed; type certificate 
holders include but are not limited to ACE Aeronautics, LLC; BHI H60 
Helicopters, LLC; Billings Flying Service Inc.; Carson Helicopters; 
Delta Enterprise; High Performance Helicopters Corp.; Northwest 
Rotorcraft LLC; Pickering Aviation, Inc.; PJ Helicopters Inc.; 
Sikorsky Aircraft Corporation; SixtyHawk TC, LLC; Skydance Blackhawk 
Operations, LLC; Timberline Helicopters, Inc.; and Unical Aviation, 
Inc.

(b) Unsafe Condition

    This AD defines the unsafe condition as a crack in an M/R blade 
spindle cuff. This condition could result in failure of an M/R blade 
spindle cuff, loss of an M/R blade, and loss of control of the 
helicopter.

(c) Effective Date

    This AD becomes effective December 3, 2020.

(d) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(e) Required Actions

    Before further flight, unless already done within the last 10 
hours time-in-service (TIS), and thereafter at intervals not to 
exceed 10 hours TIS from the last inspection:
    (1) Using 10X or higher power magnification, visually inspect 
each M/R blade spindle cuff for a crack. Pay particular attention to 
the area around each bolt hole and the upper and lower surfaces of 
the leading and trailing edges of each M/R blade spindle cuff.
    (2) If there is a crack, replace the M/R blade spindle cuff 
before further flight.

[[Page 68431]]

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Boston ACO Branch, FAA, may approve AMOCs for 
this AD. Send your proposal to: Kristopher Greer, Aerospace 
Engineer, Boston ACO Branch, Compliance and Airworthiness Division, 
FAA, 1200 District Avenue, Burlington, Massachusetts 01803; 
telephone 781-238-7799; email [email protected].
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, the FAA suggests 
that you notify your principal inspector, or lacking a principal 
inspector, the manager of the local flight standards district office 
or certificate holding district office before operating any aircraft 
complying with this AD through an AMOC.

(g) Additional Information

    Sikorsky Safety Advisory No. SSA-S70-08-002, dated December 11, 
2008, and Sikorsky Technical Manual Preventative Maintenance 
Services 10 Hour/14 Day (30 Hour/42 Day) Inspection Checklist 1-70-
PMS-1, dated December 1, 2014, which are not incorporated by 
reference, contain additional information about the subject of this 
AD. For service information identified in this AD, contact your 
local Sikorsky Field Representative or Sikorsky's Service 
Engineering Group at Sikorsky Aircraft Corporation, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-946-4337 (1-800-Winged-S); email 
[email protected]. Operators may also log on to 
the Sikorsky 360 website at https://www.sikorsky360.com. You may 
view a copy of the service information at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-
321, Fort Worth, TX 76177.
    Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor 
Head--Main Rotor Spindle Cuff.

    Issued on October 23, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-23929 Filed 10-28-20; 8:45 am]
BILLING CODE 4910-13-P

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