[Federal Register Volume 62, Number 6 (Thursday, January 9, 1997)]
[Rules and Regulations]
[Pages 1278-1279]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-404]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-SW-03-AD; Amendment 39-9877; AD 97-01-06]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron, Inc.-
Manufactured Restricted Category Model HH-1K, TH-1F, TH-1L, UH-1A, UH-
1B, UH-1E, UH-1F, UH-1H, UH-1L, and UH-1P Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to Bell Helicopter Textron, Inc. (BHTI)-manufactured 
restricted category Model HH-1K, TH-1F, TH-1L, UH-1A, UH-1B, UH-1E, UH-
1F, UH-1H, UH-1L, and UH-1P helicopters, that requires a one-time 
inspection of the tail rotor slider (slider) to verify that it was 
manufactured with the correct outside diameter. This amendment is 
prompted by a United States (U.S.) Army Safety of Flight message that 
reports that some sliders may have been improperly manufactured with an 
undersized wall thickness by U.S. Army vendors. The actions specified 
by this AD are intended to prevent fatigue failure of the slider, which 
could cause loss of tail rotor control and subsequent loss of control 
of the helicopter.

EFFECTIVE DATE: February 13, 1997.

FOR FURTHER INFORMATION CONTACT: Mr. Uday Garadi, Aerospace Engineer, 
Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 
Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222-5157, fax 
(817) 222-5961.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to Bell Helicopter

[[Page 1279]]

Textron, Inc. (BHTI)-manufactured restricted category Model HH-1K, TH-
1F, TH-1L, UH-1A, UH-1B, UH-1E, UH-1F, UH-1H, UH-1L, and UH-1P 
helicopters was published in the Federal Register on September 5, 1996 
(61 FR 46742). That action proposed to require a one-time inspection of 
the tail rotor slider (slider) to verify that it was manufactured with 
the correct outside diameter.
    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 as proposed, with one exception. The word 
``barrel'' was added to paragraph (a) of the AD to indicate that the 
splined shaft of the slider is also known as the barrel of the slider. 
This change neither increases the costs associated with the AD nor 
increases the scope of the AD.
    The FAA estimates that 80 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 0.5 work hour per 
helicopter to accomplish the required inspection, and that the average 
labor rate is $60 per work hour. Replacement of the slider requires 8 
hours, and required parts cost approximately $72 per helicopter. Based 
on these figures, the total cost impact of the AD on U.S. operators is 
estimated to be $46,560 if replacement of the slider is required in all 
of the fleet.
    The regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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 adding a new airworthiness directive 
to read as follows:

AD 97-01-06  California Department of Forestry; Erickson Air Crane 
Co.; Garlick Helicopters; Hawkins and Powers Aviation, Inc.; 
International Helicopters, Inc.; Smith Helicopters; Southwest 
Florida Aviation; West Coast Fabrications; Western International 
Aviation, Inc.; Williams Helicopter Technology, Inc.; and UNC 
Helicopters: Amendment 39-9877. Docket No. 96-SW-03-AD.

    Applicability: Bell Helicopter Textron, Inc.-manufactured Model 
HH-1K, TH-1F, TH-1L, UH-1A, UH-1B, UH-1E, UH-1F, UH-1H, UH-1L, and 
UH-1P helicopters, certificated in the restricted category.

    Note 1: This AD applies to each helicopter identified in the 
preceding applicability provision, regardless of whether it has been 
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 use the authority 
provided in paragraph (b) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition, or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any helicopter from the applicability of this AD.

    Compliance: Required within 5 hours time-in-service after the 
effective date of this AD, unless accomplished previously.
    To prevent fatigue failure of the tail rotor slider (slider), 
which could cause loss of the tail rotor and subsequent loss of 
control of the helicopter, accomplish the following:
    (a) Using a calibrated caliper or micrometer, measure the 
outside diameter of the splined shaft (barrel) of the slider, part 
number (P/N) 204-010-720-3 or P/N 204-010-720-003, at two points 
that are 90 degrees apart on the outside circumference of the 
barrel, one-half to one inch from either end of the slider. If the 
outside diameter of the slider is less than 1.300 inches, remove the 
slider and replace it, prior to further flight, with a slider that 
has an outside diameter of 1.300 inches or greater.
    (b) 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, Rotorcraft Certification Office, 
Rotorcraft 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, Rotorcraft Certification 
Office.

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

    (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, Rotorcraft Certification Office, 
Rotorcraft 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, Rotorcraft Certification 
Office.

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

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (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 February 13, 1997.

    Issued in Fort Worth, Texas, on December 31, 1996.
Larry M. Kelly,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 97-404 Filed 1-8-97; 8:45 am]
BILLING CODE 4910-13-U