On February 2, 2001, the FAA issued emergency AD 2001-03-52, which is applicable to certain Bombardier Model CL-600-2B16 (CL-604) series airplanes.
Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, recently notified the FAA that an unsafe condition may exist on certain Bombardier Model CL-600-2B16 (CL-604) series airplanes. The TCCA reported a recent incident that occurred during a flight test in which, during the initial takeoff rotation, an airplane pitched up at a significantly high rate resulting in a natural stall. After the initial pushover from the stall, the airplane stalled again when the pilot attempted to raise the nose a second time.
Investigation revealed that fuel migration in the center fuel tank caused a center of gravity shift. The fuel tanks are not baffled, which allows fuel to migrate when the airplane pitches up. Such fuel migration under conditions of acceleration and/or climb, if notcorrected, could result in the airplane exceeding the aft center of gravity limit, and consequent loss of control of the airplane.
Correction of Typographical Error
The FAA has revised paragraph (a) of this AD to correct a typographical error that appeared in the emergency AD. The typographical error referenced Canadair Challenger CL-604 Airplane Flight Manual (AFM) PSP-606-1, which does not exist, and has been changed to Canadair Challenger CL- 604 Airplane Flight Manual (AFM) PSP-604-1 in the Federal Register version of the final rule.
FAA's Conclusions
This airplane model is manufactured in Canada and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, TCCA has kept the FAA informed of the situation described above. The FAA has examined the findings of the TCCA, reviewedall available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.
Explanation of the Requirements of the Rule
Since the unsafe condition described is likely to exist or develop on other airplanes of the same type design registered in the United States, the FAA issued emergency AD 2001-03-52 to prevent fuel migration under conditions of acceleration and/or climb, which could result in the airplane exceeding the aft center of gravity limit, and consequent loss of control of the airplane. The AD requires revising the FAA-approved Airplane Flight Manual to provide the flight crew with revised aft center of gravity (CG) limits that prevent fuel migration from resulting in a rearward shift of the CG to the degree that will result in controllability problems.
Since it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary to the public interest, and good cause existed to make the AD effective immediately by individual notices issued on February 2, 2001, to all known U.S. owners and operators of Bombardier Model CL-600-2B16 (CL-604) series airplanes. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to make it effective as to all persons.
Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the 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 that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NM-27-AD." The postcard will be date stamped and returned to the commenter.
Regulatory Impact
The regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policiesand Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, 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: