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

[Federal Register Volume 67, Number 203 (Monday, October 21, 2002)]
[Rules and Regulations]
[Pages 64519-64520]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-26590]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-SW-59-AD; Amendment 39-12913; AD 2002-21-07]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
the specified Sikorsky Aircraft Corporation (Sikorsky) model 
helicopters that requires removing and inspecting each main rotor 
spindle attachment bolt (bolt) to ensure that the correct bolts are 
installed. This amendment is prompted by the discovery of improper 
bolts installed on a helicopter during its production. The actions 
specified by this AD are intended to detect installation of incorrect 
bolts, which could result in reduced hub or bolt fatigue life, 
separation of the main rotor blade at the spindle attachment, and 
subsequent loss of control of the helicopter.

DATES: Effective November 25, 2002.

FOR FURTHER INFORMATION CONTACT: Kirk Gustafson, Aviation Safety 
Engineer, Boston Aircraft Certification Office, Engine and Propeller 
Directorate, FAA, 12 New England Executive Park, Burlington, MA 01803, 
telephone (781) 238-7190, fax (781) 238-7170.

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 to 
include an AD for Sikorsky Model S-76A, S-76B and S-76C helicopters was 
published in the Federal Register on June 20, 2002 (67 FR 41875). That 
action proposed to require removing and inspecting each bolt to ensure 
that the correct bolts are installed.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposal or the FAA's determination of the cost to the public. The FAA 
has determined that air safety and the public interest require the 
adoption of the rule with one change. A ``note'' has been added 
following paragraph (b)(3) referencing the alert service bulletin that 
pertains to the subject of the AD. The FAA has determined that this 
change will neither increase the economic burden on any operator nor 
increase the scope of the AD.
    The FAA estimates that 165 helicopters of U.S. registry will be 
affected by this proposed AD, that it will take approximately 6 work 
hours per helicopter to accomplish the required actions, and that the 
average labor rate is $60 per work hour. Required parts will cost 
approximately $240 per helicopter. Based on these figures, the total 
cost impact of the AD on U.S. operators is estimated to be $99,000, 
assuming all 40 bolts (per helicopter) are replaced.
    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

[[Page 64520]]

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:

2002-21-07 Sikorsky Aircraft Corporation: Amendment 39-12913. Docket 
No. 2001-SW-59-AD.

    Applicability: Model S-76A, S-76B and S-76C helicopters, except 
those having a serial number of 760501, or 760506 through 760515, 
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 (c) 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 within 1,250-hours time-in-service or 2 
years, whichever comes first, unless accomplished previously.
    To detect installation of an incorrect main rotor spindle 
attachment bolt (bolt), which could result in reduced hub or bolt 
fatigue life, separation of the main rotor blade at the spindle 
attachment, and subsequent loss of control of the helicopter, 
accomplish the following:
    (a) Remove and measure each bolt to ensure that the length is 
1.181 +/-.015 inches. There are 10 bolts per rotor spindle and 40 
bolts per helicopter that require inspection.
    (1) If 1 or 2 bolts are found on any spindle that are longer 
than 1.196 inches (1.181 inches + .015-inch permissible tolerance), 
visually inspect the main rotor hub internal threads for distortion 
and the hole-bottoms for scoring.
    (i) If thread distortion or hole-bottom scoring is found, remove 
the rotor hub from service.
    (ii) If no thread distortion or hole-bottom scoring is found, 
replace all 10 bolts with new airworthy bolts.
    (2) If 3 or more bolts that exceed 1.196 inches are found on any 
spindle, remove and replace the main rotor hub with an airworthy 
main rotor hub.
    (3) If any bolt is found that is shorter than 1.166 inches 
(1.181 inches -.015 permissible tolerance), replace it with a new 
airworthy bolt.
    (b) Report the results of the inspections of the main rotor hubs 
whenever the bolts exceed 1.196 inches in length, within 5 calendar 
days of the inspection, to the Manager, Boston Aircraft 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone: (781) 
238-7150; fax: (781) 238-7170. Include the following information in 
the report:
    (1) Serial number of the helicopter.
    (2) Quantity of incorrect bolts.
    (3) Description of thread distortion or hole-bottom scoring 
caused by each bolt. Information collection requirements contained 
in this AD have been approved by the Office of Management and Budget 
(OMB) under the provisions of the Paperwork Reduction Act of 1980 
(44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 
2120-0056.

    Note 2: Sikorsky Aircraft Corporation Alert Service Bulletin No. 
76-65-52 (321), dated July 24, 2001, pertains to the subject of this 
AD.

    (c) 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, Engine and Propeller Directorate, 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.

    (d) 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.
    (e) This amendment becomes effective on November 25, 2002.

    Issued in Fort Worth, Texas, on October 4, 2002.
Eric D. Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 02-26590 Filed 10-18-02; 8:45 am]
BILLING CODE 4910-13-P

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