AD 98-03-02

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model CL-600-1A11 and CL-600-2A12 series airplanes, that requires replacement of the anti-noise filter on the standby and auxiliary power unit (APU) fuel pump assemblies with a new filter. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent electrical arcing between the internal wiring and casing of the anti-noise filter on the standby and APU fuel pump assemblies, and consequent increased risk of fuel tank explosion or fire.

Final rule

98-03-02 BOMBARDIER, INC. (Formerly Canadair): Amendment 39-10294. Docket 97-NM- 256-AD.
Applicability: Model CL-600-1A11 series airplanes, as listed in Bombardier Canadair Challenger Alert Service Bulletin A600-0644, Revision 01, dated March 31, 1995; and Model CL-600-2A12 series airplanes, as listed in Bombardier Canadair Challenger Alert Service Bulletin A601-0441, Revision 01, dated March 31, 1995; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes 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 (c) 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 electrical arcing between the internal wiring and casing of the anti-noise filter on the standby and auxiliary power unit (APU) fuel pump assemblies, and consequent increased risk of fuel tank explosion or fire, accomplish the following:

(a) Within 100 flight hours after the effective date of this AD, replace the anti-noise filter on the standby and auxiliary power unit (APU) fuel pump assemblies with a new filter, in accordance with Part B of Bombardier Canadair Challenger Alert Service Bulletin A600-0644, Revision 01, dated March 31, 1995 (for Model CL-600-1A11 series airplanes), or Bombardier Canadair Challenger Alert Service Bulletin A601-0441, Revision 01, dated March 31, 1995 (for Model CL-600- 2A12 seriesairplanes); as applicable.

(b) As of the effective date of this AD, no person shall install on any airplane a fuel pump having part number (P/N) 600-62966-25 or 600-62966-27 with an anti-noise filter having P/N 160-151501 (prior to revision H stamped on the part) installed.

(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 replacement shall be done in accordance with Bombardier Canadair Challenger Alert Service Bulletin A600-0644, Revision 01, dated March 31, 1995; Bombardier Canadair Challenger Alert Service Bulletin A601-0441, Revision 01, dated March 31, 1995; as applicable. 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, 10 Fifth Street, Third Floor, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington,DC.

NOTE 3: The subject of this AD is addressed in Canadian airworthiness directive CF-97-02, dated February 25, 1997.

(f) This amendment becomes effective on March 6, 1998.

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 Bombardier Model CL-600-1A11 and CL-600-2A12 series airplanes was published in the Federal Register on November 19, 1997 (62 FR 61706). That action proposed to require replacement of the anti-noise filter on the standby and auxiliary power unit (APU) fuel pump assemblies with a new filter.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received.
The commenter supports the proposed rule.

Conclusion
After careful review of the available data, including the comment noted above, 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 84 Model CL-600-1A11 and CL-600-2A12 series airplanes ofU.S. registry will be affected by this 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 $5,689 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $578,676, or $6,889 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, 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. 106(g), 40113, 44701.

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