[Federal Register Volume 59, Number 156 (Monday, August 15, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-17868]


[[Page Unknown]]

[Federal Register: August 15, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 92-ASW-50; Amendment 39-8934; AD 94-12-06]

 

Airworthiness Directives; Schweizer Aircraft Corporation and 
Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A 
Series Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to Schweizer Aircraft Corporation and Hughes 
Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH-55A series 
helicopters, that currently requires repetitive inspections and 
replacement of certain lower belt drive pulley bearings (pulley 
bearings). This amendment retains the present AD requirements and adds 
an alternate pulley bearing to the requirements of the AD. This 
amendment is prompted by the introduction of an alternate pulley 
bearing into service by Schweizer Aircraft Corporation. The actions 
specified by this AD are intended to prevent failure of the pulley 
bearings, loss of power to the rotor systems, and subsequent loss of 
control of the helicopter.

DATES: Effective on September 19, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 19, 1994.

ADDRESSES: The service information referenced in this AD may be 
obtained from Schweizer Aircraft Corporation, P.O. Box 147, Elmira, New 
York 14902. This information may be examined at the Federal Aviation 
Administration (FAA), Office of the Assistant Chief Counsel, 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: Mr. Raymond Reinhardt, Aerospace 
Engineer, FAA, New York Aircraft Certification Office, Propulsion 
Branch, ANE-174, New England Region, 181 South Franklin Avenue, Valley 
Stream, New York 11581, telephone (516) 791-7421, fax (516) 791-9024.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR 39) by superseding AD 80-02-14, Amendment 
39-3668 (45 FR 3251, January 17, 1980), which is applicable to 
Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 
269A-1, 269B, 269C, and TH-55A series helicopters, was published in the 
Federal Register on July 2, 1993 (58 FR 35900). That action proposed to 
continue the present AD requirements for lower belt drive pulley 
bearings (pulley bearings), part number (P/N) 269A5050-57, and also 
proposed a one-time inspection of the pulley bearing installation, 
repetitive inspections of the pulley bearings, and an 1,800 hours' 
time-in-service life limit for pulley bearings, part number (P/N) 
269A5050-80. Pulley bearings, P/N 269A5050-80, are subject to the same 
requirements as pulley bearings, P/N 269A5050-57.
    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 only editorial changes. The FAA 
has determined that these changes will neither increase the economic 
burden on any operator nor increase the scope of the AD.
    The FAA estimates that 700 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 1.5 work hours per 
helicopter to accomplish the required actions, and that the average 
labor rate is $55 per work hour. Required parts, if needed, will cost 
approximately $635 per helicopter. Based on these figures, the total 
cost impact of the AD on U.S. operators is estimated to be $168,875 
each year assuming 175 helicopters would need new parts each year.
    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, 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [AMENDED]

    2. Section 39.13 is amended by removing Amendment 39-3668, (45 FR 
3251, January 17, 1980), and by adding a new airworthiness directive 
(AD), Amendment 39-8934, to read as follows:

94-12-06  Schweizer Aircraft Corporation and Hughes Helicopters, 
Inc.: Amendment 39-8934. Docket Number 92-ASW-50. Supersedes AD 80-
02-14, Amendment 39-3668.

    Applicability: Model 269A, 269A-1, 269B, 269C, and TH-55A 
helicopters, with lower belt drive pulley bearings, part number (P/
N) 269A5050-57 or 269A5050-80, installed, certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the lower belt drive pulley bearings 
(pulley bearings), loss of power to the rotor systems, and 
subsequent loss of control of the helicopter, accomplish the 
following:
    (a) Within the next 50 hours' time-in-service (TIS) after the 
effective date of this AD, replace all pulley bearings, P/N 
269A5050-57 or 269A5050-80, that have accumulated 1,750 or more 
hours' TIS on the effective date of this AD. For pulley bearings 
that have accumulated less than 1,750 hours' TIS on the effective 
date of this AD, replace these pulley bearings on or prior to 
attaining 1,800 hours' total TIS. If replaced with pulley bearings, 
P/N 269A5050-57 or 269A5050-80, the repetitive inspection 
requirements of paragraph (d) of this AD are applicable.

    Note: The following paragraphs of the AD, relative to bearing 
retention system inspection, cover two systems of retention. At 
delivery, all Model 269A, 269A-1, 269B, TH-55A, and certain 269C 
helicopters, serial numbers 1 through 589, were equipped with sheet 
metal lower bearing straps, P/N 269A5463. Model 269C helicopters, 
serial numbers 590 and subsequent, were equipped with machined lower 
bearing caps that are part of a 269A5573-11 ``H'' frame assembly. 
Paragraph (b) concerns the sheet metal straps and paragraph (c) 
concerns the machined caps.

    (b) Within the next 50 hours' TIS after the effective date of 
this AD, on helicopters equipped with sheet metal lower bearing 
straps, P/N 269A5463--
    (1) Inspect the pulley bearings in accordance with paragraphs a. 
through f. of Part I of Schweizer Aircraft Corporation or Hughes 
Helicopters, Inc. Service Information Notice (SIN) N-146.2, dated 
December 7, 1979, and,
    (2) Shim bearing straps in accordance with paragraph h.(2) of 
Part I of SIN N-146.2, dated December 7, 1979.
    (c) Within the next 50 hours' TIS after the effective date of 
this AD, on helicopters equipped with machined lower pulley bearing 
caps (caps) that are part of a 269A5573-11 ``H'' frame assembly, 
inspect caps and frame assembly lower bearing bore for out-of-
roundness in accordance with paragraphs l. through p., Part I of SIN 
N-164, dated December 7, 1979.
    (1) If out-of-roundness exceeds 0.001 inch Total Indicator 
Reading (T.I.R.), reverse the caps and repeat the inspections of 
paragraph (c) of this AD for both caps.
    (2) If out-of-roundness exceeds 0.001 inch T.I.R. after 
reversing and reinspecting the caps, replace both caps with two 
lower bearing straps, P/N 269A5463, in accordance with paragraph r. 
of Part I of SIN N-164, dated December 7, 1979.
    (d) Within 300 hours' TIS after accomplishing paragraphs (b) or 
(c) of this AD, and thereafter at intervals not to exceed 300 hours' 
TIS from the last inspection, inspect the pulley bearings in 
accordance with paragraph a. through e. of Part III of SIN N-164, 
dated December 7, 1979.
    (e) Before returning any helicopter equipped with a replacement 
``H'' frame assembly to service, accomplish the inspections of 
paragraphs (b) or (c) of this AD as appropriate.
    (f) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used when approved by the Manager, New York 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, New York Aircraft Certification Office.

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

    (g) 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.
    (h) The inspections and replacements shall be done in accordance 
with Schweizer Aircraft Corporation SIN N-164 and SIN N-146.2, both 
dated December 7, 1979. This incorporation by reference was approved 
by 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 Schweizer 
Aircraft Corporation, P.O. Box 147, Elmira, New York 14902. Copies 
may be inspected at the FAA, Office of the Assistant Chief Counsel, 
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.
    (i) This amendment becomes effective on September 19, 1994.

    Issued in Fort Worth, Texas, on June 17, 1994.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 94-17868 Filed 8-12-94; 8:45 am]
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