Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A Helicopters

[Federal Register Volume 67, Number 52 (Monday, March 18, 2002)]
[Rules and Regulations]
[Pages 11893-11895]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-6330]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-SW-46-AD; Amendment 39-12674; AD 2002-05-06]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation Model S-
76A Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD) for Sikorsky Aircraft Corporation Model S-76A helicopters that 
currently requires a service life limit on certain landing gear parts 
based on hours time-in-service (TIS). This amendment adds another 
method of calculating the life limit for certain landing gear parts 
based on cycles and requires the operator to choose and record the 
method of calculating the service life of each part in the rotorcraft 
history or equivalent record. This amendment also requires replacing 
the part based upon either the maximum hours TIS or the maximum cycles 
but not both. This amendment is prompted by the need to add flight 
cycles as a method of calculating the life limit for certain landing 
gear parts based on fatigue analyses. The actions specified by this AD 
are intended to add or revise the retirement life for certain landing 
gear parts to prevent fatigue failure of the landing gear and 
subsequent loss of control of the helicopter.

DATES: Effective April 22, 2002.

FOR FURTHER INFORMATION CONTACT: Richard Noll, Aviation Safety 
Engineer,

[[Page 11894]]

Boston Aircraft Certification Office, 12 New England Executive Park, 
Burlington, MA 01803, telephone (781) 238-7160, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 by 
superseding AD 86-09-11, Amendment 39-5298 (51 FR 17009, May 8, 1986), 
for Sikorsky Model S76A helicopters, was published in the Federal 
Register on October 12, 2001 (66 FR 52073). That action proposed 
retaining a life limit based on hours TIS but also allowing the life 
limit to be based on cycles for certain landing gear parts. That action 
also proposed selecting a method for calculating the life limit of the 
landing gear parts, recording that method in the rotorcraft history or 
equivalent records, and using only that method throughout the life of 
the part. A cycle is defined as one takeoff to a hover or other mode of 
flight and one landing.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comment received.
    The manufacturer suggests removing all references to specific dates 
and pages in the maintenance manual because those references could 
change in future revisions and lead to confusion for the operators. The 
FAA agrees; however, that information was only included in the NPRM as 
part of the discussion and was not included in the regulatory text and 
is not included in the final rule.
    That commenter also states that in Table 1 the correct part number 
for the main landing gear axle is 1945E85 and not 195E85, and the life 
limit for the main landing gear retraction actuator piston is 33,000 
and not 33,300 hours TIS. The FAA agrees and has corrected this AD 
accordingly.
    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes are minor 
corrections and will only minimally increase the economic burden on 
operators and will not increase the scope of the AD.
    The FAA estimates that 87 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 2 work hours per 
helicopter to accomplish the required actions, and that the average 
labor rate is $60 per work hour. Based on these figures, the total cost 
impact of the AD on U.S. operators is estimated to be $10,440.
    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (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); 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by removing Amendment 39-5298 (51 FR 
17009, May 8, 1986), and by adding a new airworthiness directive (AD), 
to read as follows:

2002-05-06  Sikorsky Aircraft Corporation: Amendment 39-12674, 
Docket No. 2000-SW-46-AD. Supersedes AD 86-09-11, Amendment 39-5298, 
Docket No. 86-ASW-12.

    Applicability: Model S-76A helicopters, certificated in any 
category.

    Note 1: This AD applies to each helicopter identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise modified, altered, or repaired in the area subject to the 
requirements of this AD. For helicopters that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (e) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue failures of the main and nose landing gear 
parts and subsequent loss of control of the helicopter, accomplish 
the following:
    (a) Within 50 hours time-in-service (TIS), determine either the 
hours TIS or cycles accumulated on each part listed in Table 1 or 
Table 2 of this AD, as applicable. A cycle is a takeoff to a hover 
or other mode of flight and a landing.
    (1) If neither the hours TIS nor cycles are known for an 
affected part, assume the rotorcraft's total hours TIS are the hours 
TIS for that part.
    (2) If only one history is known for the part (either hours TIS 
or cycles), use that method for tracking the remaining life of that 
part.
    (3) Thereafter, record in the rotorcraft history or equivalent 
record the selected method of calculating the life limit for each 
landing gear part, and record either the accumulated hours TIS or 
cycles for the selected method.
    (b) Before further flight, remove from service each part listed 
in the following Table 1 of this AD on or before reaching the 
applicable life limit:

                                                     Table 1
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                                                                                              Life
                Component                                     Part No.                       limit    Life limit
                                                                                           hours TIS    cycles
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(1) Main Landing Gear:
    (i) Cylinder........................  1945E2                                              30,300     136,350
    (ii) Axle Support Fitting...........  1945C12                                              9,600      43,200
    (iii) Pin, Universal to Cylinder....  1945C29                                             23,800     107,100
    (iv) Drag Brace Rod End.............  1945E35                                             38,200     171,900
    (v) Upper Torque Arm................  1945E46                                             37,900     170,550
    (vi) Lower Torque Arm...............  1945C47                                             16,200      72,900

[[Page 11895]]

 
    (vii) Axle..........................  1945E85                                             23,380     105,210
    (viii) Rod End, Positioning Rod.....  1945E235                                            19,100      85,950
    (ix) Retraction Actuator:
        (A) Outer Cylinder..............  1945E302,1945F302                                    7,100      31,950
        (B) Piston......................  1945E314                                            33,000     148,500
        (C) Piston Rod End..............  01-747-061                                           8,000      36,000
(2) Nose Landing Gear:
    (i) Fork............................  1944E60                                             42,500     191,250
    (ii) Cylinder.......................  1944C2,1944E2                                       18,500      83,250
    (iii) Drag Brace Actuator:
        (A) Cylinder Terminal...........  1944D201                                            28,800     129,600
        (B) Piston Rod..................  1944E204                                            22,000      99,000
----------------------------------------------------------------------------------------------------------------

    (c) For helicopters modified by Supplemental Type Certificate 
(STC) SH568NE, before further flight, remove from service each part 
listed in the following Table 2 of this AD on or before reaching the 
applicable life limit:

                                                     Table 2
----------------------------------------------------------------------------------------------------------------
                                                                                              Life
                Component                                     Part No.                       limit    Life limit
                                                                                           hours TIS    cycles
----------------------------------------------------------------------------------------------------------------
(1) Main Landing Gear:
    (i) Cylinder........................  1945E2, 2071-2                                      24,000     108,000
    (ii) Piston.........................  1945E4, 2071-4                                      28,600     128,700
    (iii) Axle Support Fitting..........  1945C12, 2071-12                                     7,400      33,300
    (iv) Pin, Universal to Cylinder.....  1945C29, 2071-29                                    16,000      72,000
    (v) Pin, Positioning Rod to Upper     1945A32, 2071-32                                    25,000     112,500
     Torque Arm.
    (vi) Drag Brace Rod End.............  1945E35, 2071-35                                    23,864     107,388
    (vii) Upper Torque Arm..............  1945E46, 2071-46                                    26,829     120,730
    (viii) Lower Torque Arm.............  1945C47, 2071-47                                    11,928      53,676
    (ix) Lower Drag Brace...............  1945E74, 2071-74                                    46,000     207,000
    (x) Retraction Brace................  1945E76A11, 1945E76A12                              41,000     184,500
                                          2071-76-11, 2071-76-12
    (xi) Axle...........................  1945E85, 2071-85                                    23,380     105,210
    (xii) Rod End, Positioning Rod......  1945E235, 2071-235                                  13,600      61,200
    (xiii) Retraction Actuator:
        (A) Outer Cylinder..............  1945E302, 1945F302                                   7,100      31,950
        (B) Piston......................  1945E314                                            33,000     148,500
        (C) Piston Rod End..............  01-747-061                                           8,000      36,000
(2) Nose Landing Gear:
    (i) Axle............................  1944B85, 2070-85                                    49,833     224,248
    (ii) Fork...........................  1944E60, 2070-60                                    32,000     144,000
    (iii) Piston........................  1944E4, 2070-4                                      35,878     161,451
    (iv) Cylinder.......................  1944C2, 1944E2, 2070-2                              13,500      60,750
    (v) Drag Brace Actuator:
        (A) Cylinder Terminal...........  1944D201, 2070-201                                  23,000     103,500
        (B) Piston Terminal.............  1944E212B, 2070-212                                 40,000     180,000
        (C) Piston Rod..................  1944E204                                            22,000      99,000
----------------------------------------------------------------------------------------------------------------

    (d) This AD revises the Limitations section of the maintenance 
manual by establishing or revising the retirement lives for the 
affected parts shown in Tables 1 and 2 of this AD and establishing 
cycle counting as an additional method to determine retirement for 
the affected parts. Installing STC SH568NE affects the retirement 
life of certain parts.
    (e) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Boston Aircraft Certification 
Office, FAA. Operators shall submit their requests through an FAA 
Principal Maintenance Inspector, who may concur or comment and then 
send it to the Manager, Boston Aircraft Certification Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Boston Aircraft Certification Office.

    (f) Special flight permits may be issued in accordance with 14 
CFR 21.197 and 21.199 to operate the helicopter to a location where 
the requirements of this AD can be accomplished.
    (g) This amendment becomes effective on April 2, 2002.

    Issued in Fort Worth, Texas, on March 5, 2002.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 02-6330 Filed 3-15-02; 8:45 am]
BILLING CODE 4910-13-U

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