[Federal Register Volume 61, Number 247 (Monday, December 23, 1996)]
[Proposed Rules]
[Pages 67503-67505]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-32434]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-SW-28-AD]


Airworthiness Directives; Bell Helicopter Textron, Inc. Model 
214ST 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 Bell Helicopter Textron, Inc. 
(BHTI) Model 214ST helicopters. This proposal would require creation of 
a component history card using a Retirement Index Number (RIN) system; 
would establish a system for tracking increases to the accumulated RIN; 
and would establish a maximum accumulated RIN for the pillow block 
bearing bolts (bearing bolts). This proposal is prompted by fatigue 
analyses and tests that show certain bearing bolts fail sooner than 
originally anticipated because of the unanticipated high number of 
takeoffs and external load lifts utilizing high-power settings in 
addition to the time-in-service (TIS) accrued under other operating 
conditions. The actions specified by the proposed AD are intended to 
prevent fatigue failure of the bearing bolts, which could result in 
failure of the main rotor system and subsequent loss of control of the 
helicopter.

DATES: Comments must be received by February 21, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Assistant Chief Counsel, Attention: 
Rules Docket No. 94-SW-28-AD, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas 76137. Comments may be inspected at this location between 9:00 
a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Bell Helicopter Textron, Inc., Product Support 
Department, P.O. Box 482, Fort Worth, Texas, 76101.

FOR FURTHER INFORMATION CONTACT: Mr. Charles Harrison, Aerospace 
Engineer, FAA, Rotorcraft Certification Office, Rotorcraft Directorate, 
Fort Worth, Texas 76193-0170, telephone (817) 222-5447, 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 No. 94-SW28-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. 94-SW-28-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 
76137.

[[Page 67504]]

Discussion

    This notice proposes the adoption of a new airworthiness directive 
(AD) that is applicable to BHTI Model 214ST helicopters. This proposal 
would require, within the next 25 hours TIS after the effective date of 
this AD, creation of a component history card using the RIN system for 
certain bearing bolts on the Model 214ST helicopters; a system for 
tracking increases to the accumulated RIN; and would establish a 
maximum accumulated RIN of 17,000 for the Model 214ST helicopter 
bearing bolts. Fatigue analyses and tests by the manufacturer show that 
certain bearing bolts fail sooner than originally anticipated because 
of the unanticipated high number of takeoffs and external load lifts 
utilizing high-power settings in addition to the TIS accrued under 
other operating conditions. This condition, if not corrected, could 
result in fatigue failure of the bearing bolts, which could result in 
failure of the main rotor system and subsequent loss of control of the 
helicopter.
    The FAA has reviewed BHTI Alert Service Bulletin (ASB) No. 214ST-
94-69, dated November 7, 1994, which describes procedures for creation 
of a component history card within the next 25 hours TIS for Model 
214ST helicopters. The ASB also describes the retirement life as 17,000 
RIN for the bearing bolts installed on the Model 214ST helicopters.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other BHTI Model 214ST helicopters of the same type 
design, the proposed AD would require creation of a component history 
card using the RIN system; a system for tracking increases to the 
accumulated RIN; and would establish a maximum accumulated RIN of 
17,000 for the Model 214ST helicopter bearing bolts.
    The FAA estimates that 6 helicopters of U.S. registry would be 
affected by this proposed AD, and that it would take (1) 24 work hours 
per helicopter to replace the affected bearing bolts due to the new 
method of determining the retirement life required by this AD; (2) 2 
work hours per helicopter to create the component history card or 
equivalent record (record); (3) 10 work hours per helicopter to 
maintain the record each year, and that the average labor rate is $60 
per work hour. Required parts would cost approximately $2,000 per 
helicopter. Based on these figures, the total cost impact of the 
proposed AD on U.S. operators for the first year is estimated to be 
$7,760 and each subsequent year to be $7,160. These costs assume 
replacement of the bearing bolts in one-sixth of the fleet each year, 
creation and maintenance of the records for all the fleet the first 
year, and creation of one-sixth of the fleet's records and maintenance 
of the records for all the fleet each subsequent year.
    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 
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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

Bell Helicopter Textron Inc.: Docket No. 94-SW-28-AD.

    Applicability: All Model 214ST helicopters with pillow block 
bearing bolts (bearing bolts), part number (P/N) 20-057-12-48D or -
50D, 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 
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 (e) 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 25 hours time-in-service (TIS) after 
the effective date of this AD, unless accomplished previously.
    To prevent fatigue failure of the bearing bolts, which could 
result in failure of the main rotor system and subsequent loss of 
control of the helicopter, accomplish the following:
    (a) Create a component history card or an equivalent record for 
the bearing bolts, P/N 20-057-12-48D or -50D.
    (b) To determine the accumulated RIN to date on parts in 
service, multiply the factored flight hour total to date by 13.6 
(round-off the result to the next higher whole number). Record on 
the component history card the accumulated Retirement Index Number 
(RIN).

    Note 2: Bell Helicopter Textron, Inc. Alert Service Bulletin 
214ST-94-69, dated November 7, 1994, pertains to this AD.

    (c) After compliance with paragraphs (a) and (b) of this AD, 
during each operation thereafter, maintain a count of each takeoff 
and external load lift performed, and at the end of each day's 
operations, increase the accumulated RIN on the component history 
cards as follows:
    (1) Increase the RIN by 2 for each takeoff.
    (2) Increase the RIN by 2 for each external load lift or, 
increase the RIN by 4 for each external load lift operation in which 
the load is picked up at a higher elevation and released at a lower 
elevation, and the difference in elevation between the pickup point 
and the release point is 200 feet or greater.
    (d) Remove the bearing bolts from service on or before attaining 
an accumulated RIN of 17,000. If any of the four bearing bolts are 
replaced based on condition, then all four bolts must be replaced at 
that time. The bolts are no longer retired based upon flight hours. 
This AD revises the Airworthiness Limitations section of the 
maintenance manual by establishing a new retirement life for the 
bearing bolts of 17,000 RIN.
    (e) 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, 
FAA, Rotorcraft Directorate. 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.


[[Page 67505]]


    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Rotorcraft Certification Office.

    (f) 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.

    Issued in Fort Worth, Texas, on December 9, 1996.
Eric Bries,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 96-32434 Filed 12-20-96; 8:45 am]
BILLING CODE 4910-13-U