[Federal Register Volume 79, Number 13 (Tuesday, January 21, 2014)]
[Rules and Regulations]
[Pages 3303-3305]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-31459]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0636; Directorate Identifier 2012-SW-065-AD; 
Amendment 39-17709; AD 2013-25-13]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation 
(Sikorsky) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for 
Sikorsky Model S-70, S-70A, and S-70C helicopters. This AD establishes 
a new life limit based on a prorated formula for certain identified 
components (parts) installed on Model S-70, S-70A, and S-70C 
helicopters after being previously installed on certain military model 
helicopters. This AD was prompted by the discovery that certain parts 
have been interchanged between military helicopter models with 
different life limits and the possibility that these same parts can be 
interchanged with civilian models with different life limits. The 
actions are intended to establish a pro-rated in service life limit for 
each identified part to prevent fatigue failure of a part and 
subsequent loss of control of the helicopter.

DATES: This AD is effective February 25, 2014.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of February 25, 
2014.

ADDRESSES: 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 [email protected]. You may review a copy of the referenced 
service information at the FAA, Office of the Regional Counsel, 
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 
76137.

Examining the AD Docket

    You may examine the AD docket on the Internet 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 AD, the economic evaluation, any 
comments received, and other information. The street address for the 
Docket Operations Office (phone: 800-647-5527) is U.S. Department of 
Transportation, Docket Operations Office, M-30, West Building Ground 
Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Michael Davison, Flight Test Engineer, 
Boston Aircraft Certification Office, Engine & Propeller Directorate, 
12 New England Executive Park, Burlington, Massachusetts 01803; 
telephone (781) 238-7156; email [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    On July 23, 2013, at 78 FR 44045, the Federal Register published 
our notice of proposed rulemaking (NPRM), which proposed to amend 14 
CFR part 39 by adding an AD that would apply to Sikorsky Model S-70, S-
70A, and S-70C helicopters. The NPRM proposed inserting the component 
life prorating formula into the airworthiness limitation section of the 
maintenance manual or instructions for continued airworthiness, 
calculating the new life limit for each part by applying the formula, 
and establishing life limits for certain parts without applying the 
formula. Furthermore, the NPRM proposed updating the component log or 
equivalent record with the new in-service life limit and replacing each 
part that has reached or exceeded its new life limit with an airworthy 
part. Lastly, the NPRM proposed prohibiting installation of any 
applicable part on a Model S-70, S-70A, or S-70C helicopter if the 
number of hours is unknown or if certain parts have been previously 
installed on a Model UH-60M helicopter. The NPRM was prompted by the 
discovery that certain parts with identical part numbers but different 
life limits have been interchanged between military helicopter models 
and the possibility that these same parts can be interchanged with 
civilian models with different life limits.
    The proposed requirements were intended to establish a pro-rated in 
service life limit for each identified part to prevent fatigue failure 
of a part and subsequent loss of control of the helicopter.

Comments

    We gave the public the opportunity to participate in developing 
this AD, but we did not receive any comments on the NPRM (78 FR 44045, 
July 23, 2013).

FAA's Determination

    We have reviewed the relevant information and determined that an

[[Page 3304]]

unsafe condition exists and is likely to exist or develop on other 
products of these same type designs and that air safety and the public 
interest require adopting the AD requirements as proposed.

Costs of Compliance

    We estimate that this AD affects 9 helicopters of U.S. Registry.
    We estimate that the cost to insert pages into the aircraft's 
airworthiness limitation section is negligible.

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

    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) Is not a ``significant rule'' under 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.

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 (AD):

2013-25-13 Sikorsky Aircraft Corporation (Sikorsky): Amendment 39-
17709; Docket No. FAA-2013-0636; Directorate Identifier 2012-SW-065-
AD.

(a) Applicability

    This AD applies to Model S-70, S-70A, and S-70C helicopters, 
certificated in any category, with the following parts installed:
    (1) Spindle and liner assembly, part number (P/N) 38023-10374-
041;
    (2) Main Rotor Hub, P/N 70070-10046-055 and -056;
    (3) Main Rotor Spindle nut, P/N 70102-08105-102;
    (4) Main Rotor Control Horn, P/N 70102-08111-047;
    (5) Main Rotor Hub, P/N 70103-08112-041 and -047;
    (6) Rotating Swashplate, P/N 70104-08001-044 and -045;
    (7) Main Rotor Shaft Extension, P/N 70351-08186-043;
    (8) Main Rotor Gear Box Housing, P/N 70351-38110-043, -044, and 
-045;
    (9) Main Rotor Shaft, P/N 70351-38131-042;
    (10) Output Bevel Gear and Shaft, P/N 70358-06620-101 and -102;
    (11) Left Tie Rod Assembly, P/N 70400-08115-043, -045, -046, and 
-047;
    (12) Forward Bellcrank Support Assembly, P/N 70400-08162-042;
    (13) Lateral Servo Bellcrank, P/N 70400-08166-041; or
    (14) Tail Rotor Servo Assembly, P/N 70410-06520-044 through -
046.

(b) Unsafe Condition

    This AD defines the unsafe condition as a critical part 
remaining in service beyond its life limit due to previously being 
installed on a different helicopter model with higher usage and 
flight loads. This condition could result in fatigue failure of a 
critical part and subsequent loss of control of the helicopter.

(c) Effective Date

    This AD becomes effective February 25, 2014.

(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

    (1) Within 25 hours time-in-service (TIS):
    (i) Insert into the airworthiness limitation section of the 
maintenance manual or instructions for continued airworthiness the 
component life prorating formula in Section 1.1.3, Component Life 
Prorating, pages 1-25 and 1-26, of Sikorsky Technical Manual TM 1-
70-23AW-2, Change 3, dated April 15, 2012.
    (ii) Using the service life limits in Table 1 to Paragraph (e) 
of this AD, apply the component life prorating formula and calculate 
the new life limit for each specified part. If the number of hours 
of a part is unknown, that part cannot be installed on a Sikorsky 
Model S-70, S-70A, or S-70C helicopter. Do not calculate a new life 
limit for the part where the Model SH-60 life limit is higher than 
the life limit on Models S-70, S-70A, and S-70C.

                                            Table 1 to Paragraph (e)
----------------------------------------------------------------------------------------------------------------
                                                                  S-70, S-70A, S-
                  P/N                       Part description        70C service       UH-60M         SH-60B/F
                                                                       life        service life    service life
----------------------------------------------------------------------------------------------------------------
38023-10374-041.......................  Spindle and Liner                  8,000           6,400          10,000
                                         Assembly.
70070-10046-055 and -056..............  Main Rotor Hub..........           5,100           3,100          \1\N/A
70102-08105-102.......................  Main Rotor Spindle Nut..           8,000           6,400          10,000
70102-08111-047.......................  Main Rotor Control Horn.    20,000/1,300          10,000         \1\ N/A
                                                                   \2\/2,500 \2\
70103-08112-041 and -047..............  Main Rotor Hub..........           5,100           3,100         \1\ N/A
70104-08001-044-045...................  Rotating Swashplate.....          11,000           4,600           9,600
70351-08186-043.......................  Main Rotor Shaft                  14,000           4,900          16,000
                                         Extension.
70351-38110-043, -044, and -045.......  Main Rotor Gear Box               11,000           4,000           9,000
                                         Housing.
70351-38131-042.......................  Main Rotor Shaft........          17,000           5,200          19,000
70358-06620-101 and -102..............  Output Bevel Gear and              5,000           1,800         \1\ N/A
                                         Shaft.

[[Page 3305]]

 
70400-08115-043, -045, -046, and -047.  Left Tie Rod Assembly...          14,000           4,600           6,300
70400-08162-042.......................  Forward Bellcrank           14,000/2,500           5,600           7,600
                                         Support Assembly.                   \3\
70400-08166-041.......................  Lateral Servo Bellcrank.          20,000          11,000          14,000
70410-06520-044 through -046..........  Tail Rotor Servo                  15,000          11,000         \1\ N/A
                                         Assembly.
----------------------------------------------------------------------------------------------------------------
\1\ There is no service life limit listed because the parts on Model SH-60B/F have a different P/N than the
  parts on Models S-70, S-70A, and S-70C.
\2\ For serial number (S/N) 32479930 through 324791859, with CAGE code 60078, the life limit is 1,300 hours TIS.
For S/N A241-07543 through A241-07594, A241-07706 through A241-07755, A241-07768 through A241-07771, A241-07800
  through A241-07831, R241-00101 through R241-00355, R241-00701 through R241-00966, and R241-01001 through R241-
  01166, the life limit is 2,500 hours TIS.
\3\ For S/N A-367-00001 through A367-00035, with CAGE code 78286, the life limit is 2,500 hours TIS.

    (iii) Record the newly-established life limit of each part on 
the part's component log card or equivalent record.
    (2) After establishing the new life limit, replace each part 
that has reached or exceeded its new life limit with an airworthy 
part before further flight.
    (3) Do not install the following parts on a Model S-70, S-70A, 
or S-70C helicopter if they have been previously installed on a 
Model UH-60M helicopter:
    (i) Bolt, self retaining, P/N 70103-08801-102;
    (ii) Bifilar, P/N 70107-08400-046;
    (iii) Aft Bellcrank, P/N 70400-08102-045;
    (iv) Aft Walking Beam Assembly, P/N 70400-08104-048; or
    (v) Close Tolerance Bolt, P/N 70400-26802-102 and -103.

(f) Alternative Methods of Compliance (AMOC)

    (1) The Manager, Boston Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: Michael Davison, 
Flight Test Engineer, Boston Aircraft Certification Office, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, 
Massachusetts 01803; telephone (781) 238-7156; email 
[email protected].
    (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) Subject

    Joint Aircraft Service Component (JASC) Code: 6220 Main Rotor 
Hub, 6230 Main Rotor Mast/Swashplate, 6320 Main Rotor Gearbox, 6310 
Engine/Transmission Coupling, 6510 Tail Rotor Drive Shaft.

(h) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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) Pages 1-25 and 1-26, Section 1.1.3, Component Life 
Prorating, of Sikorsky Technical Manual TM 1-70-23AW-2, Change 3, 
dated April 15, 2012.
    (ii) Reserved.
    (3) For Sikorsky 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 [email protected].
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137. 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, call (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Fort Worth, Texas, on December 5, 2013.
Kim Smith,
Directorate Manager, Rotorcraft Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-31459 Filed 1-17-14; 8:45 am]
BILLING CODE 4910-13-P