[Federal Register Volume 66, Number 71 (Thursday, April 12, 2001)]
[Proposed Rules]
[Pages 18884-18886]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-9075]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-SW-02-AD]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron Canada Model 
407 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM); rescission.

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SUMMARY: This amendment proposes rescinding an existing Airworthiness 
Directive (AD) for Bell Helicopter Textron Canada (BHTC) Model 407 
helicopters. That AD currently requires, before further flight, 
imposing never exceed velocity (Vne) restrictions on the helicopter. 
The requirements of that AD were intended to prevent tail rotor blades 
from striking the tailboom, separation of the aft section of the 
tailboom with the tail rotor gearbox and vertical fin, and subsequent 
loss of control of the helicopter. That AD was prompted by an accident 
suspected of being the result of a tail rotor strike caused by high 
airspeed. Since the issuance of that AD, accident investigation 
findings have not substantiated that a tail rotor strike caused by high 
airspeed was the cause of the accident. This action would require 
rescinding that AD. This

[[Page 18885]]

proposal is prompted by the FAA's determination that the Vne 
restrictions and accompanying actions imposed by that AD do not correct 
an unsafe condition.

DATES: Comments must be received on or before May 14, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA) Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2001-SW-02-AD, 2601 Meacham Blvd., Room 
663, 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. You may also send comments electronically to the 
Rules Docket at the following address: [email protected].

FOR FURTHER INFORMATION CONTACT: Sharon Miles, Aviation Safety 
Engineer, FAA, Rotorcraft Directorate, Regulations Group, Fort Worth, 
Texas 76193-0111, 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 document 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 proposal must submit a self-
addressed, stamped postcard on which the following statement is made: 
``Comments to Docket No. 2001-SW-02-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 Regional Counsel, Attention: Rules Docket No. 
2001-SW-02-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Discussion

    On January 30, 2001, the FAA issued AD 2001-01-52, Amendment 39-
12100 (66 FR 9031, February 6, 2001), for BHTC Model 407 helicopters. 
That AD requires, before further flight, reducing the maximum approved 
Vne to 100 KIAS if an airspeed-actuated pedal stop is not installed or 
to 110 KIAS if an airspeed-actuated pedal stop is installed; inserting 
a copy of the AD into the RFM; installing a temporary placard on the 
flight instrument panel to indicate the reduced Vne limit; and 
installing a new redline Vne limit at either 100 or 110 KIAS, as 
specified in the AD, on all airspeed indicators. That action was 
prompted by an accident in which a helicopter was destroyed on water 
impact following an in-flight occurrence at approximately 140 KIAS. One 
of the possible contributing factors was an in-flight tail rotor strike 
to the tailboom. As a precautionary measure, pending further 
investigation into the accident, and after reviewing the AD issued by 
the certifying authority for the helicopter (Transport Canada), the FAA 
issued AD 2001-01-52 to reduce the Vne.

Actions Since Issuing Previous AD

    Since issuing AD 2001-01-52, preliminary accident investigation 
findings do not substantiate that the accident resulted from a tail 
rotor strike caused by high airspeed. Information provided by BHTC and 
reviewed by the FAA supports these findings. Transport Canada has 
issued a superseding AD, CF-2001-01R1, dated April 3, 2001, stating 
that the Vne restriction is no longer necessary. Transport Canada 
advises that no data has emerged from the investigation to confirm that 
the accident was initiated by a tail rotor strike. While the 
possibility of a tail rotor strike has not been completely discounted 
as the cause of the accident, a tail rotor strike occurrence while 
operating within the approved flight envelope has been discounted. The 
ongoing accident investigation is currently considering other factors.

FAA's Conclusions

    After reviewing the available data, the FAA has determined that it 
is appropriate to rescind AD 2001-01-52 to prevent operators from 
performing an unnecessary action. The Vne restrictions and accompanying 
actions imposed by that AD do not correct an unsafe condition. The 
ongoing investigation found no information to indicate that the 
accident was caused by a tail rotor strike during flight at high 
airspeed. The cause of the accident precipitating AD 2001-01-52 remains 
under investigation.
    This proposed action would rescind AD 2001-01-52. Rescission of AD 
2001-01-52 would constitute only such action and if followed by a final 
action would not preclude the agency from issuing another action in the 
future nor would it commit the agency to any course of action in the 
future.

Cost Impact

    The FAA estimates that 200 helicopters of U.S. registry are 
affected by AD 2001-01-52. The actions that are currently required by 
that AD take approximately 3 work hours per helicopter to manufacture 
and install each airspeed limitation placard. The average labor rate is 
$60 per work hour. Required parts cost approximately $10 per 
helicopter. Based on these figures, the total cost impact of the AD on 
U.S. operators is estimated to be $38,000 to install an airspeed 
limitation placard on all helicopters in the U.S. fleet. However, 
adopting this proposed rescission would eliminate those costs.

Regulatory Impact

    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.

[[Page 18886]]

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 adding an AD removing Amendment 39-
12100 to read as follows:

Bell Helicopter Textron Canada: Docket No. 2001-SW-02-AD. Rescinds 
AD 2001-01-52, Amendment 39-12100.

    Applicability: Model 407 helicopters, certificated in any 
category.

    Issued in Fort Worth, Texas, on March 5, 2001.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-9075 Filed 4-11-01; 8:45 am]
BILLING CODE 4910-13-P