[Federal Register Volume 59, Number 3 (Wednesday, January 5, 1994)]
[Proposed Rules]
[Pages 555-556]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-140]


[[Page Unknown]]

[Federal Register: January 5, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-SW-17-AD]

 

Airworthiness Directives; Bell Helicopter Textron, Inc. Model 
205A, 205A-1, 205B, 212, and 412 Series Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Bell Helicopter Textron, 
Inc. Model 205A, 205A-1, 205B, 212, and 412 series helicopters. This 
proposal would require removal and replacement of a certain design main 
transmission lower planetary spider (spider) and would establish a 
2,500 hours' time-in-service retirement life for the spider. This 
proposal is prompted by five failures of the spider that occurred 
during the manufacturer's fatigue tests. The actions specified by the 
proposed AD are intended to prevent fatigue failure of the spider, 
failure of the main transmission, and subsequent loss of control of the 
helicopter.

DATES: Comments must be received by February 22, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Assistant Chief Counsel, Attention: 
Rules Docket No. 93-SW-17-AD, 2601 Meacham Boulevard, Fort Worth, Texas 
76137. Comments may be inspected at this location between 9 a.m. and 3 
p.m., Monday through Friday, except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, 
Texas 76101. This information may be examined at the FAA, Office of the 
Assistant Chief Counsel, 2601 Meacham Boulevard, room 663, Fort Worth, 
Texas.

FOR FURTHER INFORMATION CONTACT: Mr. Scott Horn, Aerospace Engineer, 
Rotorcraft Certification Office, FAA, Rotorcraft Directorate, Fort 
Worth, Texas 76193-0170, telephone (817) 222-5159, fax (817) 222-5959.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 93-SW-17-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Office of the Assistant Chief Counsel, Attention: Rules 
Docket No. 93-SW-17-AD, 2601 Meacham Boulevard, Fort Worth, Texas 
76137.

Discussion

    This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to Bell Helicopter Textron, Inc. 
(BHTI) Model 205A, 205A-1, 205B, 212, and 412 series helicopters, 
equipped with a main transmission lower planetary spider (spider), part 
number (P/N) 412-040-785-101. During recent BHTI fatigue tests, five 
spiders failed due to structural fatigue. Previously, there was no 
retirement life established for the spider. However, based on these 
test results, the FAA proposes to establish a 2,500 hours' time-in-
service (TIS) retirement life for this design spider. This condition, 
if not corrected, could result in fatigue failure of the spider, 
failure of the main transmission, and subsequent loss of control of the 
helicopter.
    The FAA has reviewed and approved (1) BHTI Alert Service Bulletin 
(ASB) 205-93-54, dated June 18, 1993, applicable to Model 205A-1 
helicopters; (2) ASB 205B-93-16, dated June 18, 1993, applicable to 
Model 205B helicopters; (3) ASB 212-93-83, dated June 18, 1993, 
applicable to Model 212 helicopters; and (4) ASB 412-93-72, Revision A, 
dated June 18, 1993, applicable to Model 412 helicopters. These ASBs 
describe procedures for the removal, retirement, and replacement of 
certain spiders when they reach 2,500 hours' TIS.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require removal and replacement of spiders with less 
than 2,400 hours' TIS, prior to or upon attaining 2,500 hours' TIS or, 
for spiders with 2,400 hours' or more TIS, within the next 100 hours' 
TIS. This AD also establishes a retirement life of 2,500 hours' TIS. 
The actions would be required to be accomplished in accordance with the 
service bulletins described previously.
    The FAA estimates that 40 helicopters of U.S. registry would be 
affected by this proposed AD, that it would take approximately 26 
workhours per helicopter to accomplish the proposed actions, and that 
the average labor rate is $55 per workhour. Required parts would cost 
approximately $8,929 per helicopter. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$414,360.
    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 14 
CFR part 39 of the Federal Aviation Regulations 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 adding the following new 
airworthiness directive:

Bell Helicopter Textron, Inc.: Docket No. 93-SW-17-AD.
    Applicability: Model 205A, 205A-1, 205B, 212, and 412 series 
helicopters, with main transmission lower planetary spider (spider), 
part number (P/N) 412-040-785-101, installed, certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue failure of the spider, that could result in 
failure of the main transmission and subsequent loss of control of 
the helicopter, accomplish the following:
    (a) For spiders with 2,400 hours' or more time-in-service (TIS) 
on the effective date of this airworthiness directive (AD), within 
the next 100 hours' TIS remove and replace the spider with an 
airworthy spider in accordance with the Accomplishment Instructions 
of Bell Helicopter Textron, Inc. Alert Service Bulletin (ASB) 205-
93-54, dated June 18, 1993, for the Models 205A and 205A-1; ASB 
205B-93-16, dated June 18, 1993, for the Model 205B; ASB 212-93-83, 
dated June 18, 1993, for the Model 212; and ASB 412-93-72, Revision 
A, dated June 18, 1993, for the Model 412 helicopters.
    (b) For spiders with less than 2,400 hours' TIS on the effective 
date of this AD, prior to or upon attaining 2,500 hours' TIS, remove 
and replace the spider with an airworthy spider in accordance with 
the accomplishment instructions of the appropriate ASB referred to 
in paragraph (a).
    (c) This AD revises the Airworthiness Limitations Section of the 
applicable helicopter maintenance manuals by establishing a 
retirement life of 2,500 hours' TIS for the spider.
    (d) An alternative method of compliance or adjustment of the 
compliance time, which provides an acceptable level of safety, may 
be used when approved by the Manager, Rotorcraft Certification 
Office, FAA, Rotorcraft Directorate. Operators should 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Rotorcraft Certification Office.

    (e) Special flight permits may be issued in accordance with FAR 
21.197 and 21.199 to operate the helicopter to a location where the 
requirements of this AD can be accomplished.

    Issued in Fort Worth, Texas, on December 3, 1993.
James D. Erickson,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 94-140 Filed 1-4-94; 8:45 am]
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