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

[Federal Register Volume 66, Number 44 (Tuesday, March 6, 2001)]
[Rules and Regulations]
[Pages 13422-13424]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-5165]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-SW-01-AD; Amendment 39-12134; AD 2001-03-51]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 2001-03-51, which was sent 
previously to all known U.S. owners and operators of Sikorsky Aircraft 
Corporation (Sikorsky) Model S-76B and S-76C helicopters by individual 
letters. This AD requires, for certain main rotor shafts, initial and 
recurring fluorescent penetrant inspections. Replacing each affected 
main rotor shaft (shaft) on or before reaching 1,000 hours time-in-
service (TIS) is also required. This amendment is prompted by four 
reports of shaft cracks. The actions specified by this AD are intended 
to prevent failure of the shaft and subsequent loss of control of the 
helicopter.

DATES: Effective March 21, 2001, to all persons except those persons to 
whom it was made immediately effective by Emergency AD 2001-03-51, 
issued on January 30, 2001, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 21, 2001.
    Comments for inclusion in the Rules Docket must be received on or 
before May 7, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2001-SW-01-AD, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas 76137. You may also send comments electronically 
to the Rules Docket at the following address: [email protected].
    The applicable service information may be obtained from Sikorsky 
Aircraft Corporation, Attn: Manager, Commercial Tech Support, 6900 Main 
Street, Stratford, Connecticut 06614, phone (203) 386-3001, fax (203) 
386-5983. This information may be examined at the FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort 
Worth, Texas; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.

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: On January 30, 2001, the FAA issued 
Emergency AD 2001-03-51 for Sikorsky Model S-76B and S-76C helicopters, 
which requires, for certain shafts, initial and recurring fluorescent 
penetrant inspections. Replacing each affected shaft on or before 
reaching 1,000 hours TIS is also required. That action was prompted by 
four reports of shaft cracks. This condition, if not corrected, could 
result in failure of the shaft and subsequent loss of control of the 
helicopter.
    The FAA has reviewed Sikorsky Alert Service Bulletin (ASB) No. 76-
66-32A, Revision A, dated January 17, 2001, which specifies identifying 
main gear box assemblies containing certain shafts, conducting a 
recurring fluorescent penetrant inspection (FPI), and removing certain 
main gear box assemblies containing certain shafts.
    Since the unsafe condition described is likely to exist or develop 
on other Sikorsky Model S-76B and S-76C helicopters of the same type 
designs, the FAA issued Emergency AD 2001-03-51 to prevent failure of 
the shaft and subsequent loss of control of the helicopter. The AD 
requires, for certain main rotor shafts, an FPI before further flight 
and thereafter at intervals not to exceed 20 hours TIS or 80 landings, 
whichever occurs first. Replacing each affected shaft on or before 
reaching 1,000 hours TIS is also required. The actions must be 
accomplished in accordance with the ASB described previously. The short 
compliance time involved is required because the previously described 
critical unsafe condition can adversely affect the structural integrity 
of the helicopter. Therefore, FPI's and removal of each affected shaft 
are required at the specified time intervals, and this AD must be 
issued immediately.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on January 30, 2001, to all known U.S. owners and operators of

[[Page 13423]]

Sikorsky Model S-76B and S-76C helicopters. These conditions still 
exist, and the AD is hereby published in the Federal Register as an 
amendment to 14 CFR 39.13 to make it effective to all persons.
    The FAA estimates that 7 helicopters of U.S. registry will be 
affected by this AD. It will take approximately 4 work hours per 
helicopter to accomplish each FPI and 5 work hours to replace each 
shaft. The average labor rate is $60 per work hour. Required parts will 
cost approximately $25,000 per shaft. Based on these figures, the total 
cost impact of the AD on U.S. operators is estimated to be $178,780 
(assuming 1 FPI per helicopter and 1 shaft replacement on each 
helicopter). Additional FPI's would cost $240 per inspection and 
additional shaft replacements would cost $25,300 per helicopter.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications should identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available in the Rules Docket for examination by interested persons. A 
report that summarizes each FAA-public contact concerned with the 
substance of this AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their mailed 
comments submitted in response to this rule must submit a self-
addressed, stamped postcard on which the following statement is made: 
``Comments to Docket No. 2001-SW-01-AD.'' The postcard will be date 
stamped and returned to the commenter.
    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.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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, Incorporation by 
reference, 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 adding a new airworthiness directive 
to read as follows:

2001-03-51  Sikorsky Aircraft Corporation: Amendment 39-12134. 
Docket No. 2001-SW-01-AD.

    Applicability: Model S-76B and S-76C helicopters, with main 
rotor shaft assembly (shaft), part number (P/N) 76351-09630 all dash 
numbers, serial number (S/N) C213-00274, C213-00275, C213-00276, 
C213-00277, C213-00278, C213-00279, C213-00280, C213-00282, C213-
00292, C213-00294, C213-00295, C213-00296, C213-00297, C213-00299, 
and C213-00300, installed, 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 (d) 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 failure of the shaft and subsequent loss of control 
of the helicopter, accomplish the following:
    (a) Before further flight and thereafter at intervals not to 
exceed 20 hours time-in-service (TIS) or 80 landings, whichever 
occurs first, conduct a fluorescent penetrant inspection (FPI) in 
the area above the uppers shaft output seal and below the lower hub 
attachment flange in accordance with the Accomplishment 
Instructions, paragraphs 3.B.(1) through 3.B.(5), of Sikorsky 
Aircraft Corporation (Sikorsky) Alert Service Bulletin (ASB) No. 76-
66-32A, Revision A, dated January 17, 2001. Contacting Sikorsky is 
not required by this AD. If a crack is found, replace the shaft with 
an airworthy shaft before further flight.

    Note 2:  Accomplishing the FPI before further flight is not 
required if previously accomplished in accordance with the 
Accomplishment Instructions, paragraphs 3.C.(1) through 3.C.(5), of 
Sikorsky ASB No. 76-66-31B, Revision B, dated November 7, 2000.

    (b) On or before 1000 hours TIS, replace each affected shaft 
with an airworthy shaft.
    (c) This AD revises the Limitations section of the maintenance 
manual by establishing a retirement life of 1000 hours TIS for the 
affected shafts.
    (d) 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 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Boston Aircraft Certification Office.

    (e) 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 if the FPI or a 
visual inspection, using a 10X or higher magnifying glass, does not 
reveal a crack.
    (f) The FPI shall be done in accordance with the Accomplishment 
Instructions, paragraphs 3.B.(1) through 3.B.(5), of Sikorsky 
Aircraft Corporation Alert Service Bulletin No. 76-66-32A, Revision 
A, dated January 17, 2001. This incorporation by

[[Page 13424]]

reference was approved the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from Sikorsky Aircraft Corporation, Attn: Manager, 
Commercial Tech Support, 6900 Main Street, Stratford, Connecticut 
06614, phone (203) 386-3001, fax (203) 386-5983. Copies may be 
inspected at the FAA, Office of the Regional Counsel, Southwest 
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.
    (g) This amendment becomes effective on March 21, 2001, to all 
persons except those persons to whom it was made immediately 
effective by Emergency AD 2001-03-51, issued January 30, 2001, which 
contained the requirements of this amendment.


    Issued in Fort Worth, Texas, on February 20, 2001.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-5165 Filed 3-5-01; 8:45 am]
BILLING CODE 4910-13-M

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