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[Federal Register Volume 81, Number 168 (Tuesday, August 30, 2016)]
[Proposed Rules]
[Pages 59526-59528]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-20672]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-7095; Directorate Identifier 2015-SW-085-AD]
RIN 2120-AA64

Airworthiness Directives; Sikorsky Aircraft Corporation 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This 
proposed AD would require removing from service the tail gearbox center 
housing (housing) when it has 12,200 or more hours time-in-service 
(TIS). This proposed AD is prompted by fatigue analysis conducted by 
Sikorsky that determined the housing required a retirement life. The 
proposed actions are intended to prevent a crack in the housing, which 
could lead to loss of tail rotor drive and loss of helicopter control.

DATES: We must receive comments on this proposed AD by October 31, 
2016.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     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 http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
7095; or in person at the Docket Operations Office between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the economic evaluation, any comments 
received, and other information. The street address for the Docket 
Operations Office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.
    For service information identified in this proposed rule, contact 
Sikorsky Aircraft Corporation, Customer Service Engineering, 124 Quarry 
Road, Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; 
email sikorskywcs@sikorsky.com.
    You may review 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: Kristopher Greer, Aerospace Engineer, 
Boston Aircraft Certification Office, Engine & Propeller Directorate, 
FAA, 1200 District Avenue, Burlington, Massachusetts 01803; telephone 
781-238-7799; email Kristopher.Greer@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to participate in this rulemaking by submitting 
written comments, data, or views. We also invite 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 time.
    We will file in the docket all comments that we receive, as well as 
a report summarizing each substantive public contact with FAA personnel 
concerning this proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring

[[Page 59527]]

expense or delay. We may change this proposal in light of the comments 
we receive.

Discussion

    We propose to adopt a new AD for Sikorsky Model S-92A helicopters 
with a housing, part number (P/N) 92358-06107-043, installed. This 
proposed AD would establish a life limit of 12,200 hours TIS for the 
housing by requiring that the housing be removed from service when it 
reaches 12,200 hours TIS. This proposed AD is prompted by an analysis 
conducted by Sikorsky on the Model S-92A helicopter for a gross weight 
increase that revealed higher than expected loads. The housing 
currently has no life limit. Sikorsky's analysis, which used updated 
load conditions and updated fatigue analysis software, determined 
housings that remain in service beyond 12,200 hours TIS present an 
unacceptable risk of cracking. This condition could result in loss of 
tail rotor drive and loss of helicopter control.

FAA's Determination

    We are proposing this AD because we evaluated all known relevant 
information and determined that an unsafe condition exists and is 
likely to exist or develop on other products of these same type 
designs.

Related Service Information

    We reviewed Sikorsky S-92 Maintenance Manual 4-00-00, Temporary 
Revision No. 4-49, dated April 10, 2015, which establishes a 
replacement interval of 12,200 hours for housing, P/N 92358-06107-043.

Proposed AD Requirements

    This proposed AD would require, before further flight, removing 
from service any tail gearbox housing, P/N 92358-06107-043, that has 
12,200 or more hours TIS.

Costs of Compliance

    We estimate that this proposed AD would affect 80 helicopters of 
U.S. Registry and that labor costs average $85 per work hour. Based on 
these estimates, we expect the following costs. Replacing the housing 
would require 24 work-hours, and parts would cost $58,000 for a total 
cost of $60,040 per helicopter.

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.
    We are 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

    We 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. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; and
    4. 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.
    We prepared an economic evaluation of the estimated costs to comply 
with this proposed AD and placed it in the AD docket.

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 (AD):

Sikorsky Aircraft Corporation: Docket No. FAA-2015-7095; Directorate 
Identifier 2015-SW-085-AD.

(a) Applicability

    This AD applies to Sikorsky Aircraft Corporation (Sikorsky) 
Model S-92A helicopters, certificated in any category, with a tail 
gearbox center housing, part number (P/N) 92358-06107-043, 
installed.

(b) Unsafe Condition

    This AD defines the unsafe condition as a crack in a tail 
gearbox center housing. This condition could result in failure of 
the tail rotor drive and consequently loss of helicopter control.

(c) Comments Due Date

    We must receive comments by October 31, 2016.

(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, remove from service any tail gearbox 
housing, P/N 92358-06107-043, that has 12,200 or more hours time-in-
service.

(f) Alternative Methods of Compliance (AMOC)

    (1) The Manager, Boston Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: Kristopher Greer, 
aerospace engineer, Boston Aircraft Certification Office, Engine & 
Propeller Directorate, FAA, 1200 District Avenue, Burlington, 
Massachusetts 01803; telephone 781-238-7799; email 
Kristopher.Greer@faa.gov.
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest 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

    For service information identified in this AD, contact Sikorsky 
Aircraft Corporation, Customer Service Engineering, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email 
sikorskywcs@sikorsky.com. You may review a copy of the information 
at the FAA, Office of the Regional Counsel, Southwest Region, 10101 
Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: 6520, Tail Rotor 
Gearbox.

[[Page 59528]]

    Issued in Fort Worth, Texas, on August 19, 2016.
Scott A. Horn,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2016-20672 Filed 8-29-16; 8:45 am]
 BILLING CODE 4910-13-P
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