AD 94-14-08

This amendment adopts a new airworthiness directive (AD), applicable to certain Canadair Model CL-600-2B16 series airplanes, that requires inspection to detect chafing of the wiring harness of the air driven generator (ADG), modification of the wiring harness, and repair of any chafed harness. This amendment is prompted by a report that the wiring harness on certain airplanes was produced in a configuration that is subject to chafing and electrical shorting. The actions specified by this AD are intended to prevent chafing or shorting of the wiring harness, which could result in loss of ADG power to the essential bus when the ADG is deployed during an emergency situation.

Final rule

94-14-08 CANADAIR: Amendment 39-8960. Docket 93-NM-222-AD.
Applicability: Model CL-600-2B16 series airplanes having serial numbers 5099 through 5131, inclusive; certificated in any category.

NOTE 1: Airplanes having serial numbers 5001 through 5098, inclusive, are subject to the requirements of AD 91-19-01, amendment 39-8026 (which is similar in content to this amendment).

Compliance: Required as indicated, unless accomplished previously.

To prevent loss of emergency power to the essential bus when the air driven generator (ADG) is deployed, accomplish the following:

(a) Within 25 hours time-in-service after the effective date of this AD, inspect to detect chafing of the wiring harness of the ADG in accordance with Canadair Alert Service Bulletin A601-0370, Revision 1, dated April 15, 1993. If chafing is found, prior to further flight, repair in accordance with the service bulletin.

(b) Within 60 days after the effective date of this AD, modify the harness installation of the ADG in accordance with Canadair Alert Service Bulletin A601-0370, Revision 1, dated April 15, 1993.

(c) 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, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

(d) 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.

(e) The inspection and modification shall bedone in accordance with Canadair Alert Service Bulletin A601-0370, Revision 1, dated April 15, 1993. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station A, Montreal, Quebec, H3C 3G9 Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on August 10, 1994.

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 certain Canadair Model CL-600-2B16 series airplanes was published in the Federal Register on March 14, 1994 (59 FR 11735). That action proposed to require inspection to detect chafing and modification of the wiring harness of the air driven generator (ADG), and repair of any chafed harness.

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

The FAA estimates that 25 airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the required actions, and that the average laborrate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $1,375, or $55 per airplane.

The FAA estimates that it will take approximately 9 work hours per airplane to accomplish the modification and the average labor rate is $55 per work hour. Required parts will cost approximately $199 per airplane. Based on these figures, the total cost impact of the modification on U.S. operators is estimated to be $17,350, or $694 per airplane.

Based on the figures, above, the total (inspection plus modification) cost impact of the AD on U.S. operators is estimated to be $18,725, or $749 per airplane.

The total 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.

The regulations adopted herein will not have substantial direct effects on theStates, 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, Incorporation by reference, 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.

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