[Federal Register Volume 77, Number 93 (Monday, May 14, 2012)]
[Proposed Rules]
[Pages 28328-28330]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-11475]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0216; Directorate Identifier 2010-SW-025-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, which 
requires inspecting the tail rotor (T/R) pylon for a loose or missing 
fastener, a crack, damage, or corrosion and adding an internal doubler 
to the aft shear deck tunnel assembly. This proposed AD is prompted by 
the discovery of cracks in T/R pylons. The proposed actions are 
intended to detect a loose or missing fastener, a crack, damage, or 
corrosion on the T/R pylon and, if present, to repair the T/R Pylon and 
install a doubler on the aft shear deck tunnel assembly or to replace 
the T/R pylon and install the doubler on the aft shear deck tunnel 
assembly to prevent failure of the T/R pylon or other T/R components, 
and subsequent loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by July 13, 2012.

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

[[Page 28329]]

at http://www.regulations.gov 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 AD, contact 
Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical 
Support, mailstop s581a, 6900 Main Street, Stratford, CT 06614; 
telephone (800) 562-4409; email [email protected]; or at http://www.sikorsky.com. You may review the referenced service information at 
the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham 
Blvd., Room 663, Fort Worth, TX 76137.

FOR FURTHER INFORMATION CONTACT: Nicholas Faust, Aviation Safety 
Engineer, Boston Aircraft Certification Office, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803; 
telephone (781) 238-7763; email [email protected].

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 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 T/R pylon, part number (P/N) 92000-06102-041. This proposal is 
prompted by the discovery of cracks in the forward lower spar region of 
T/R pylons installed on Sikorsky
    Model S-92A helicopters. The T/R pylon supports the T/R and the 
horizontal stabilizer, and a crack in a T/R pylon could alter vibration 
characteristics of the T/R pylon, which could adversely affect fatigue 
lives of T/R components. This condition, if not corrected, could result 
in failure of the T/R pylon or other T/R components and subsequent loss 
of control of the helicopter.

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 the same type design.

Related Service Information

    We have reviewed Sikorsky Alert Service Bulletin (ASB) No. 92-53-
001, dated June 23, 2008 (ASB No. 92-53-001), and ASB No. 92-53-004B, 
Revision B, dated June 21, 2011 (ASB No. 92-53-004B). ASB No. 92-53-001 
specifies for a T/R pylon with more than 500 flight-hours a one-time 
inspection of the T/R pylon ``components and structure for obvious 
damage, cracks, corrosion, and security.'' ASB No. 92-53-004B specifies 
a one-time replacement of the T/R pylon, P/N 92000-06102-041, with T/R 
pylon, P/N 92070-20058-042, and installation of a doubler on the aft 
shear deck tunnel assembly. The ASB specifies a replacement schedule 
based on the T/R pylon's hours for specified serial numbered 
helicopters.

Proposed AD Requirements

    This proposed AD would require compliance with specified portions 
of the manufacturer's alert service bulletins. This proposal would 
require, for helicopters with 500 or more hours time-in-service (TIS), 
within 25 hours TIS and thereafter at intervals not to exceed 10 hours 
TIS, inspecting the T/R pylon for a crack, damage, corrosion, or loose 
or missing fasteners. If a crack or an area of damage or corrosion is 
found or if there is a loose or missing fastener, before further 
flight, this proposed AD would require repairing the crack, damage, or 
corrosion, and replacing any loose or missing fastener and installing a 
doubler, P/N 92070-20087-101, on the aft shear deck tunnel assembly; or 
replacing the T/R pylon, P/N 92000-06102-041, with an airworthy T/R 
pylon, P/N 92070-20058-042, and installing a doubler, P/N 92070-20087-
101, on the aft shear deck tunnel assembly. If there is no crack in the 
T/R pylon, this proposed AD would require replacing the T/R pylon, P/N 
92000-06102-041, with an airworthy T/R pylon, P/N 92070-20058-042, and 
adding a doubler, P/N 92070-20087-101, on the aft shear deck tunnel 
assembly, according to the following compliance schedule:
     For a T/R pylon with 3,750 or more hours TIS, within 12 
months;
     For a T/R pylon with 1,500 through 3,749 hours TIS, within 
24 months; and
     For a T/R pylon with 1,499 or less hours TIS, within 36 
months.
    Replacing the T/R pylon, P/N 92000-06102-041, with an airworthy T/R 
pylon, P/N 92070-20058-042, and installing doubler, P/N 92070-20087-
101, on the aft shear deck tunnel assembly, would constitute 
terminating action for the requirements of this AD.

Costs of Compliance

    We estimate that this proposed AD would affect 20 helicopters of 
U.S. Registry. We estimate that operators may incur the following costs 
in order to comply with this AD. It would take approximately 1 work-
hour per helicopter to inspect and 120 work-hours per helicopter to 
replace the T/R pylon and install the doubler. The average labor rate 
is $85 per work-hour and required parts would cost approximately 
$339,080 per helicopter. Based on these figures, we estimate the total 
cost impact of the proposed AD per helicopter to be $356,505, and the 
total cost on U.S. operators to be $7,130,100, assuming 85 inspections 
per year are performed on each helicopter and assuming replacement of 
the T/R pylon and installing the doubler on each helicopter.
    According to the Sikorsky service information, some of the costs of 
this proposed AD may be covered under warranty thereby reducing the 
cost impact on affected individuals. We do not control warranty 
coverage. Accordingly, we have included all costs in our cost estimate.

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.

[[Page 28330]]

    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

    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 (AD):

Sikorsky Aircraft Corporation: Docket No. FAA-2012-0216; Directorate 
Identifier 2010-SW-025-AD.

(a) Applicability

    This AD applies to Sikorsky Aircraft Corporation (Sikorsky) 
Model S-92A helicopters, with a tail rotor (T/R) pylon, part number 
(P/N) 92000-06102-041, certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a loose or missing 
fastener, a crack, damage, or corrosion on the T/R pylon that could 
result in failure of the T/R pylon or other T/R components, and 
subsequent loss of control of the helicopter.

(c) 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.

(d) Required Actions

    (1) For helicopters with 500 or more hours time-in-service 
(TIS), within 25 hours TIS and thereafter at intervals not to exceed 
10 hours TIS, inspect each T/R pylon for a crack, damage, corrosion, 
or a loose or missing fastener in accordance with the Accomplishment 
Instructions, paragraph 3.A.(4)(a) through paragraph 3.A.(4)(f), and 
referring to Figure 1 of Sikorsky Alert Service Bulletin (ASB) No. 
92-53-001, dated June 23, 2008, except you are not required to 
contact Sikorsky Customer Service Engineering per paragraph 
3.A.(4)(c)1 of ASB 92-53-001, dated June 23, 2008.
    (2) If there is a crack, damage, corrosion, or a loose or 
missing fastener, before further flight, either:
    (i) If within allowable tolerances, repair each crack and each 
area of damage or corrosion and replace any loose or missing 
fastener; or
    (ii) Replace the T/R pylon, (P/N) 92000-06102-041, with T/R 
pylon, P/N 92070-20058-042, as follows:
    (A) Conduct the Total Indicated Run-out procedure on the No. 4 
and No. 5 T/R drive shafts and remove the T/R pylon; and
    (B) Install the doubler, P/N 92070-20087-101, as follows:
    (1) For helicopters, serial numbers (S/Ns) 920006 through 
920082, on the aft shear deck tunnel assembly, P/N 92204-05103-041 
or -045, in accordance with the Accomplishment Instructions, 
paragraph 3.B.(1) through 3.B.(30) and while referring to Figures 1, 
2, and 4 of Sikorsky ASB No. 92-53-004B, Revision B, dated June 21, 
2011 (92-53-004B).
    (2) For helicopters, S/Ns 920083 through 920124, on the aft 
shear deck tunnel assembly, P/N 92204-05103-043, in accordance with 
the Accomplishment Instructions, paragraph 3.C.(1) through 3.C.(21) 
and referring to Figures 3 and 4 of ASB 92-53-004B.
    (3) If there is no crack in the T/R pylon, replace T/R pylon, P/
N 92000-06102-041, with T/R pylon, P/N 92070-20058-042, and install 
doubler, P/N 92070-20087-101, on the aft shear deck tunnel assembly 
as specified in paragraphs (2)(ii)(A) through (2)(ii)(B) of this AD, 
according to the following:
    (i) For a T/R pylon with 3,750 or more hours TIS, replace and 
install doubler within 12 months.
    (ii) For a T/R pylon with 1,500 through 3,749 hours TIS, replace 
and install doubler within 24 months.
    (iii) For a T/R pylon with 1,499 or less hours TIS, replace and 
install doubler within 36 months.
    (4) Replacing T/R pylon, P/N 92000-06102-041, with T/R pylon, P/
N 92070-20058-042, and installing internal tail cone doubler, P/N 
92070-20087-101, on the aft shear deck tunnel assembly, constitutes 
terminating action for the requirements of this AD.

(e) Alternative Methods of Compliance (AMOC)

    (1) The Manager, Boston Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: Nicholas Faust, 
Aviation Safety Engineer, Boston Aircraft Certification Office, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803; telephone (781) 238-7763; email 
[email protected].
    (2) For operations conducted under a Part 119 operating 
certificate or under 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.

(f) Additional Information

    For service information identified in this AD, contact Sikorsky 
Aircraft Corporation, Attn: Manager, Commercial Technical Support, 
mailstop s581a, 6900 Main Street, Stratford, CT 06614; telephone 
(800) 562-4409; email [email protected]; or at http://www.sikorsky.com. You may review this service information at the 
FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham 
Blvd., Room 663, Fort Worth, TX 76137.

(g) Subject

    Joint Aircraft Service Component (JASC) Code: 5340, Fuselage 
Main, Attach Fittings.

    Issued in Fort Worth, Texas, on May 2, 2012.
Carlton N. Cochran,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-11475 Filed 5-11-12; 8:45 am]
BILLING CODE 4910-13-P