[Federal Register Volume 65, Number 90 (Tuesday, May 9, 2000)]
[Proposed Rules]
[Pages 26783-26785]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-11522]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-42-AD]


Airworthiness Directives; Bell Helicopter Textron Canada (BHTC) 
Model 430 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD) applicable to BHTC Model 430 helicopters. 
That AD requires inspecting all four main rotor adapter assemblies for 
evidence of flapping and lead-lag contact. That AD also requires 
installing a never-exceed-velocity (VNE) placard with markings on the 
airspeed indicator glass and instrument case and a revision to the 
rotorcraft flight manual (RFM) to reflect the airspeed revision. This 
action would provide mandatory terminating action for requirements of 
that AD by replacing the fluidlastic damper blade sets with improved 
sets that incorporate a pressure indicator to detect loss of damper 
fluid. This proposal is prompted by the need for a positive means of 
detecting loss of damper fluid that could result in main rotor tip path 
plane separation. The actions specified by the proposed AD are intended 
to prevent increased vibrations, damage to the main rotor system, and 
subsequent loss of control of the helicopter.

DATES: Comments must be received on or before July 10, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-42-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137. You may also send comments electronically to 
the Rules Docket at the following address: [email protected]. 
Comments may be inspected at this location between 9:00 a.m. and 3:00 
p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Sharon Miles, Aviation Safety 
Engineer, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 
Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5122, fax 
(817) 222-5961.

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 mailed 
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. 99-SW-42-AD.'' The postcard will be date 
stamped and returned to the commenter.

[[Page 26784]]

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-42-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.

Discussion

    On September 26, 1997, the FAA issued AD No. 97-15-16, Amendment 
39-10152 (62 FR 52653, October 9, 1997). That AD requires inspecting 
the BHTC Model 430 helicopter main rotor adapter assemblies for 
evidence of flapping and lead-lag contact. That AD also requires 
installing a VNE placard, with markings to reflect the airspeed 
restriction, and inserting revisions to the RFM to reflect the airspeed 
revisions. That action was prompted by a report of a main rotor tip 
path plane separation, which occurred during a ferry flight at airspeed 
of more than 140 knots indicated airspeed. The requirements of that AD 
are intended to prevent tip path plane separation, increased 
vibrations, damage to the main rotor system, and subsequent loss of 
control of the helicopter.
    Transport Canada, the airworthiness authority for Canada, notified 
the FAA that an unsafe condition may exist on BHTC Model 430 
helicopters. Transport Canada advises that a main rotor tip path plane 
separation on a Model 430 helicopter was caused by the limited damping 
characteristics of the elastomeric lead-lag dampers.
    Since the issuance of AD 97-15-16, BHTC has issued Alert Service 
Bulletin (ASB) 430-97-4, dated December 14, 1997, and ASB 430-98-8, 
dated December 31, 1998, that provide for replacing the fluidlastic 
damper blade sets with improved sets, part number (P/N) 430-310-104-
105. The improved fluidlastic damper blade sets incorporate a pressure 
indicator to provide a positive means of leak detection, thereby 
replacing the requirements of ASB 430-97-2, dated July 11, 1997, and 
ASB 430-97-4, dated December 19, 1997.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other BHTC Model 430 helicopters of the same type 
design, the proposed AD would maintain the same requirements as AD 97-
15-16 until an improved fluidlastic damper blade set, P/N 430-310-104-
105, is installed that incorporates a pressure indicator to detect loss 
of damper fluid.
    The FAA estimates that 7 helicopters of U.S. registry would be 
affected by this proposed AD, that it would take approximately 11 work 
hours per helicopter to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. The required parts would cost 
approximately $122,945 per set of 4. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$865,235 to replace the damper blade sets in the entire fleet.
    The regulations proposed herein would 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 proposal would not have federalism implications 
under Executive Order 13132.
    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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-10152 (62 FR 
52653, October 9, 1997), and by adding a new airworthiness directive 
(AD), to read as follows:

Bell Helicopter Textron Canada: Docket No. 99-SW-42-AD. Supersedes 
AD 97-15-16, Amendment 39-10152, Docket 97-SW-24-AD.

    Applicability: Model 430 helicopters, 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 (d) 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 as indicated, unless accomplished 
previously.
    To prevent tip path plane separation, increased vibrations, 
damage to the main rotor system, and subsequent loss of control of 
the helicopter, accomplish the following:
    (a) Before further flight:
    (1) Inspect all four main rotor adapter assemblies for flapping 
contact between the adapter liners and the upper stop assembly 
plugs. Refer to Figures 1, 2, and 3 of the Accomplishment 
Instructions of Bell Helicopter Textron Canada (BHTC) Alert Service 
Bulletin (ASB) No. 430-97-2, dated July 11, 1997. Flapping contact 
is indicated by the scrubbing (or smudging) of the adapter liner 
surface, characteristic of relative motion between the surfaces of 
the adapter lines and upper stop assembly plugs.
    (2) Inspect all four main rotor adapter assemblies for lead-lag 
contact between the adapter pads and the yoke assembly. Refer to 
Figures 1 and 2 of the Accomplishment Instructions of BHTC ASB No. 
430-97-2, dated July 11, 1997. Lead-lag contact is indicated by a 
permanent indentation or split in the surface of the adapter pads.
    (3) If the inspections in paragraphs (a)(1) or (a)(2) of this AD 
reveal that there has been contact, inspect and replace the main 
rotor yoke and stop assemblies in accordance with Part I, No. 3 of 
the Accomplishment Instructions of BHTC ASB No. 430-97-2, dated July 
11, 1997, except return of any damaged upper stops to the 
manufacturer is not required.
    (4) For helicopters with skid landing gear or retractable 
landing gear, remove the existing never-exceed-velocity (VNE) 
placard from the overhead console and install VNE placard, P/N 430-
075-208-107, or P/N 430-075-208-109, as applicable, in accordance 
with Part II, of the Accomplishment Instructions of BHTC ASB No. 
430-97-2, dated July 11, 1997.
    (5) Install on each airspeed indicator a red arc between 120 
knots and 150 knots to indicate that airspeeds above 120 knots 
indicated airspeed are prohibited. Install a slippage mark on each 
airspeed indicator glass and instrument case.
    (6) Insert the temporary revisions, BHT-430-FM-1 and BHT-430-
FMS-1, as appropriate, both dated July 7, 1997, into the rotorcraft 
flight manual.
    (b) Within 100 hours time-in-service, (1) Remove the fluidlastic 
damper blade set, P/N 430-310-100-101 or 430-310-107-101 in 
accordance with the Accomplishment

[[Page 26785]]

Instructions of ASB 430-97-4, dated December 19, 1997, Part 1, steps 
1 through 5, and install damper blade set, P/N 430-310-104-105, in 
accordance with the Accomplishment Instructions, Part I, of BHTC ASB 
430-98-8, dated December 31, 1998.
    (2) Return pilot and copilot airspeed indicators to their 
original configuration by removing the markings specified by 
paragraph (a)(5) of this AD.
    (3) Remove the temporary revisions, BHT 430-FM-1 or BHT-430-FMS-
1, as appropriate, both dated July 7, 1997. Insert the temporary 
revisions, BHT-430-FM-1, or BHT-430-FMS-1, as appropriate, both 
dated December 11, 1998, into the rotorcraft flight manual.
    (c) If paragraph (b)(1) was previously accomplished by 
installation of fluidlastic damper blade set, P/N 430-310-104-103, 
remove fluidlastic damper blade set, P/N 430-310-104-103, and 
install fluidlastic damper blade set, P/N 430-310-104-105, in 
accordance with the Accomplishment Instructions of BHTC ASB 430-98-
8, dated December 31, 1998.
    (d) 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, Regulations Group, FAA, 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, Regulations Group.

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

    (e) 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.

    Note 3: The subject of this AD is addressed in Transport Canada 
(Canada) AD No. CF-97-23R1, dated March 30, 1999.


    Issued in Fort Worth, Texas, on April 28, 2000.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-11522 Filed 5-8-00; 8:45 am]
BILLING CODE 4910-13-P