[Federal Register Volume 66, Number 51 (Thursday, March 15, 2001)]
[Proposed Rules]
[Pages 15062-15063]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-6389]



[[Page 15062]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-SW-05-AD]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation Model S-
76A, S-76B, and S-76C Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NRPM).

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SUMMARY: This document proposes superseding an existing airworthiness 
directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-
76A, S-76B, and S-76C helicopters. That AD currently requires, before 
further flight, performing a fluorescent penetrant inspection (FPI) of 
the main rotor shaft assembly (shaft). Also, a recurring FPI and visual 
inspection for a cracked shaft are required by that AD. That AD also 
requires replacing the shaft with an airworthy shaft before further 
flight if a crack is found. This action would require replacing certain 
serial numbered shafts with an airworthy shaft before further flight. 
This proposal is prompted by a further investigation and a 
determination that the inspections can be safely eliminated if certain 
serial numbered shafts are removed from service before further flight. 
The actions specified by the proposed AD are intended to prevent 
failure of the shaft and subsequent loss of control of the helicopter.

DATES: Comments must be received by April 16, 2001.

ADDRESSES: Submit comments to Docket No. 2001-SW-05-AD in one of the 
following ways:
     Mail comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2001-SW-05-AD, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas 76137. You may also send a request for a copy of 
the NPRM to that address. If you want us to acknowledge receipt of your 
mailed comments, you must include a self-addressed, stamped postcard on 
which the Docket Number is written. We will date-stamp your postcard 
and mail it back to you.
     E-mail comments to [email protected].
    You may examine this Docket (including any comments and service 
information) at the FAA, Office of the Regional Counsel, Southwest 
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137 between 9 
a.m. and 3 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Wayne Gaulzetti, Aviation Safety 
Engineer, Boston Aircraft Certification Office, 12 New England 
Executive Park, Burlington, MA 01803, telephone (781) 238-7156, fax 
(781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to submit any written relevant data, views, or 
arguments. Submit your comments as specified under the ADDRESSES 
caption. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify it. We will file a report in the Docket that 
summarizes each FAA contact with the public during the comment period 
that is related to the substantive part of this rule.
    We will consider comments received by the closing date. The 
proposals or format contained in this document may be changed because 
of the comments received.

Discussion

    On November 3, 2000, the FAA issued AD 2000-23-51, to require a 
one-time FPI of the shaft. That AD was prompted by the discovery of a 
cracked shaft having 477 hours time-in-service. On November 9, 2000, 
the FAA issued superseding Emergency AD 2000-23-52 to require an 
initial and recurring FPI and a daily visual inspection of the shaft 
and replacing any shaft found cracked with an airworthy shaft. The 
requirements of that AD are intended to prevent failure of the shaft 
and subsequent loss of control of the helicopter.
    Since the issuance of that AD, further investigation and 
engineering analysis have revealed that daily visual inspections are 
unnecessary and that certain shafts require an immediate and repetitive 
FPI and a new retirement life while certain others require replacing 
before further flight. The inspections and new retirement life for 
certain serial numbered shafts are addressed in AD 2001-03-51, Docket 
2001-SW-01-AD. This AD would require, before further flight, replacing 
certain shafts installed on the Sikorsky Model S-76A helicopters. The 
FAA has reviewed Sikorsky Aircraft Corporation Alert Service Bulletin 
No. 76-66-32A (319A), Revision A, dated January 17, 2001, which 
specifies removing certain shafts from service and implementing a 
recurring FPI for certain other shafts.
    We have identified an unsafe condition that is likely to exist or 
develop on other Sikorsky Model S-76A helicopters of the same type 
design. The proposed AD would require, before further flight, replacing 
each shaft, part number 76351-09030-all dash numbers, serial number 
B015-00700 through B015-00706, with an airworthy shaft.

Regulatory Impact

    We estimate that 3 helicopters of U.S. registry would be affected 
by this proposed AD, that it would take approximately 5 work hours per 
helicopter to replace the shafts, and that the average labor rate is 
$60 per work hour. Required parts would cost approximately $19,000 per 
helicopter. Based on these figures, the total cost impact of the AD on 
U.S. operators is estimated to be $57,900.
    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that 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); 
and (3) if promulgated, 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. You can get a copy of 
the draft regulatory evaluation prepared for this action from the Rules 
Docket. A copy of it may be obtained by contacting the Rules Docket at 
the mailing address listed under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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.

[[Page 15063]]

Sec. 39.13  [Amended]

    2. FAA amends Sec. 39.13 by removing Amendment 39-12095 (66 FR 
8507, February 1, 2001), and by adding the following new airworthiness 
directive (AD):

         Federal Aviation Administration (FAA), Docket No. 2001-SW-05-AD, Sikorsky Aircraft Corporation
                       [Subject: Model S-76A, S-76B, and S-76C Main Rotor Shaft Assembly]
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(a) Comment Due Date................................  FAA must receive comments by April 16, 2001.
(b) Affected Documents..............................  This AD supersedes AD 2000-23-52, Amendment 39-12095,
                                                       Docket No. 2000-SW-61-AD.
(c) Applicability...................................  Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-
                                                       76B, and S-76C helicopters with main rotor shaft assembly
                                                       (shaft), part number (P/N) 76351-09030--all dash numbers,
                                                       installed, certificated in any category.
(d) Unsafe Condition................................  To prevent failure of the shaft and subsequent loss of
                                                       control of the helicopter.
(e) Compliance......................................  Required before further flight, unless accomplished
                                                       previously.
(f) Required Actions................................  Replace each affected shaft, serial number B015-00700
                                                       through B015-00706, with an airworthy shaft.
(g) Other Provisions................................  (1) Alternative Methods of Compliance (AMOC):
                                                      (i) You may use an AMOC or adjust the time you need to
                                                       meet the requirements of this AD if your alternative
                                                       provides an acceptable level of safety and if the
                                                       Manager, Boston Aircraft Certification Office (ACO),
                                                       approves your alternative.
                                                         (ii) Submit your request for approval through an FAA
                                                          Principal Maintenance Inspector, who may add comments
                                                          and then forward it to the Manager, Boston ACO.
                                                         (iii) You can get information about the existence of
                                                          already approved AMOC's by contacting the FAA, Boston
                                                          Aircraft Certification Office, 12 New England
                                                          Executive Park, Burlington, MA 01803, telephone (781)
                                                          238-7156, fax (781) 238-7199.
                                                      (2) Modifications, Alterations, or Repairs:
                                                         This AD applies to each helicopter identified in the
                                                          applicability paragraph, even if it has been modified,
                                                          altered, or repaired in the area subject to this AD.
                                                          If that change in any way affects accomplishing the
                                                          required actions, you must request FAA approval for an
                                                          AMOC. Your request should assess the effect of the
                                                          change on the unsafe condition addressed by this AD.
                                                      (3) Special Flight Permits:
                                                         The FAA may issue you a special flight permit under 14
                                                          CFR 21.197 and 21.199 to operate your helicopter to a
                                                          location where you can comply with this AD.
(h) Material Incorporated by Reference..............  None.
(i) Related Information.............................  Sikorsky Alert Service Bulletin No. 76-66-32A (319A),
                                                       Revision A, dated January 17, 2001, pertains to the
                                                       subject of this AD.
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    Issued in Fort Worth, Texas, on March 5, 2001.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-6389 Filed 3-14-01; 8:45 am]
BILLING CODE 4910-13-U