AD 97-01-12

This amendment adopts a new airworthiness directive (AD), applicable to all Airtell International, Inc., Centaurus Model C3-100 GPWS equipment that is installed on any type of airplane, that requires replacement of this equipment with a similar type of equipment that meets specific performance requirements. This amendment is prompted by results of an investigation, which revealed that, under certain circumstances, the Centaurus GPWS equipment does not provide the flight crew with aural warnings to indicate that the airplane is descending. The actions specified by this AD are intended to prevent failure of the GPWS equipment to provide such aural warnings. If the flight crew relies on receiving such warnings and the GPWS equipment fails to provide those warnings, the ability of the flight crew to prevent the airplane from impacting the ground may be inhibited.

Final rule.

97-01-12 AIRTELL INTERNATIONAL, INC.: Amendment 39-9883. Docket 96-NM-242-AD.

Applicability: Centaurus Model C3-100 ground proximity warning system (GPWS) equipment, as installed in, but not limited to, the following airplanes, certificated in any category:

Beech 99 series airplanes;
Beech 200 series airplanes;
Dassault Aviation Model Mystere-Falcon 200 series airplanes;
EMBRAER (Empresa Brasileira de Aeronautica S.A.) EMB-110 series airplanes;
Fairchild Aircraft Model SA226-TC series airplanes;
Fairchild Aircraft Model SA227-AT series airplanes; and
Grumman Model G-73 Mallard airplanes.
Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the GPWS equipment to provide certain aural warnings, which could inhibit the ability of the flight crew to prevent the airplane from impacting the ground, accomplish the following:

(a) Within 60 days after the effective date of this AD, remove and replace Centaurus Model C3-100 GPWS equipment with a similar type of equipment that meets minimum performance standards specified in Technical Standard Order (TSO) C-92b, dated August 19, 1976. Accomplish the actions in accordance with a method approved by the Manager, Flight Test and Systems Branch, ANM-111, FAA, Transport Airplane Directorate.

(b) 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, Flight Test and Systems Branch, ANM-111. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Flight Test and Systems Branch, ANM-111.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Flight Test and Systems Branch, ANM-111.

(c) 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 airplane to a location where the requirements of this AD can be accomplished.

(d) This amendment becomes effective on February 25, 1997.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to all Airtell International, Inc., Centaurus Model C3-100 ground proximity warning system (GPWS) equipment that is installed on any type of airplane was published in the Federal Register on October 18, 1996 (61 FR 54364). That action proposed to require removal and replacement of Centaurus Model C3-100 GPWS equipment with a similar type of equipment that meets specific performance requirements.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.

Conclusion
The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
The FAA estimates that 30 airplanes of U.S. registry will be affected bythis AD, that it will take approximately 20 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $16,000 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $516,000, or $17,200 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact
The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from 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.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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.

39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: