Transport Canada Aviation (TCA), which is the airworthiness authority for Canada, notified the FAA that an unsafe condition may exist on certain Bombardier Model CL-215-1A10 and CL-215-6B11 series airplanes. The TCA advises that fatigue cracks have been found in the lower caps of the wing front spar and rear spar at wing station 51 of several in-service airplanes. This condition, if not detected and corrected in a timely manner, could result in reduced structural integrity of the airplane.
Explanation of Relevant Service Information
Transport Canada Aviation issued Canadian airworthiness directives CF-92-26, dated December 23, 1992, and CF-93-07, dated March 26, 1993, in order to assure the continued airworthiness of these airplanes in Canada. Those Canadian airworthiness directives cite Bombardier Inc. Canadair Alert Wires 215-A454, dated December 23, 1992, and 215-A463, dated March 26, 1993, respectively, which provide procedures for ultrasonic inspection to detect cracking of the rear and front spar lower cap at the left and right wing station 51, and repair, if necessary.
Subsequently, the manufacturer issued Canadair Alert Service Bulletin 215-A454, Revision 1, dated May 25, 1995, and Canadair Alert Service Bulletin 215-A463, Revision 1, dated May 25, 1995, which describe procedures for repetitive ultrasonic inspections to detect fatigue cracking of the lower caps of the wing front and rear spars at wing station 51. For airplanes on which any discrepancy is found, the alert service bulletins also describe procedures for rework of the lower caps, and follow-on visual inspection of the front or rear spar web area and the lower skin area from inside the wing box.
FAA's Conclusions
These airplane models are manufactured in Canada and are type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.19) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, TCA has kept the FAA informed of the situation described above. The FAA has examined the findings of TCA, reviewed all 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 Requirements of the Rule
Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, this AD is being issued to detect and correct cracking of the lower caps of the wing front spar and rear spar, which could result in reduced structural integrity of the airplane. This AD requires accomplishment of the actions specified in the service bulletins described previously, except as discussed below.
Differences Between This Rule and the Alert Service Bulletins
Operators should note that, although the alert service bulletins specify thatthe manufacturer may be contacted for disposition of certain repair conditions, this AD requires that repair of those conditions be accomplished in accordance with a method approved by the FAA.
Cost Impact
None of the airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future.
Should an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 16 work hours to accomplish the required inspections, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this AD would be $960 per airplane, per inspection cycle.
Determination of Rule's Effective Date
Since this AD action does not affect any airplane that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, prior notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register.
Comments Invited
Although this action is in the form of a final rule and was not preceded by notice and 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 97-NM-332-AD." The postcard will be date stamped and returned to the commenter.
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: