[Federal Register Volume 62, Number 201 (Friday, October 17, 1997)]
[Proposed Rules]
[Page 53979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-27584]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-SW-21-AD]


Airworthiness Directives; Eurocopter Deutschland GmbH (ECD) Model 
BO 105 C and BO 105 S Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Proposed rule; withdrawal.

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SUMMARY: This action withdraws a notice of proposed rulemaking (NPRM) 
that proposed a new airworthiness directive (AD), applicable to 
Eurocopter Deutschland GmbH (ECD) (Eurocopter Deutschland) Model BO 105 
C and BO 105 S helicopters. That action would have required modifying 
the main relay box by replacing the voltage regulator; modifying the 
cockpit overhead panel by installing two additional switches; and 
performing a functional test of the new voltage regulator, generators, 
and new switches. Since the issuance of the NPRM, the Federal Aviation 
Administration (FAA) has determined that the modification proposed is 
only necessary for Instrument Flight Rule (IFR) configurations, and 
since there is no IFR FAA type-design approval for the affected models, 
it is unnecessary to issue an AD.

FOR FURTHER INFORMATION CONTACT: Mr. Lance Gant, Aerospace Engineer, 
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham 
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5114, fax (817) 
222-5961.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to add a new airworthiness 
directive (AD), applicable to Eurocopter Deutschland Model BO 105 C and 
BO 105 S helicopters, was published in the Federal Register on February 
13, 1997 (62 FR 6746). The proposed rule would have required modifying 
the main relay box 1VE; modifying the cockpit overhead panel, and 
performing a functional test of the new voltage regulator, generators, 
and new switches for the affected helicopters. That action was prompted 
by an in-service report of a helicopter that experienced a generator 
overvoltage. The proposed actions were intended to prevent failure of 
essential electrical equipment that could result in spatial 
disorientation and subsequent loss of control of the helicopter.
    Since the issuance of that NPRM, the FAA has determined that the 
need for overvoltage protection is associated with the IFR requirement 
to have certain avionics available; however, there is no FAA IFR type-
design approval for the affected models, therefore there is no type 
design model on which to issue an AD.
    Upon further consideration and review of this new data, the FAA has 
determined that the unsafe condition no longer exists and is extremely 
unlikely to develop. Accordingly, the proposed rule is hereby 
withdrawn.
    Withdrawal of this notice of proposed rulemaking constitutes only 
such action, and does not preclude the agency from issuing another 
notice in the future, nor does it commit the agency to any course of 
action in the future.
    Since this action only withdraws a notice of proposed rulemaking, 
it is neither a proposed nor a final rule and therefore, is not covered 
under Executive Order 12866, the Regulatory Flexibility Act, or DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979).

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Withdrawal

    Accordingly, the notice of proposed rulemaking, Docket No. 96-SW-
21-AD, published in the Federal Register on February 13, 1997 (62 FR 
6746), is withdrawn.

    Issued in Fort Worth, Texas, on October 7, 1997.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 97-27584 Filed 10-16-97; 8:45 am]
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