Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This proposal would require repetitive inspections for cracking of the upper and lower web of the engine support beam at fuselage station 640, and repair if necessary. This proposal also would provide an optional terminating action for the repetitive inspections. This action is necessary to prevent failure of the engine support beam, a principal structural element, which could result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by December 1, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-321-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-321-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT:

James Delisio, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York 11581; telephone (516) 256-7521; fax (516) 568-2716.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NM-321-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-321-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, notified the FAA that an unsafe condition may exist on certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. TCCA advises that cracks have been found on the upper and lower web of the engine support beam (ESB) at fuselage station (FS) 640 on several airplanes. The subject airplanes had more than 19,000 flight hours and 16,000 flight cycles. This condition, if not corrected, could result in failure of the ESB, a principal structural element, which could result in reduced structural integrity of the airplane.

Explanation of Relevant Service Information

Bombardier has issued Alert Service Bulletin A601R-53-059, Revision “D,” dated July 2, 2003; including Appendix A, undated; and Appendix B, dated August 6, 2002. That service bulletin describes procedures for performing repetitive external detailed visual inspections for cracking of the upper and lower web of the ESB at FS 640. The service bulletin specifies to contact the manufacturer for repair instructions for any cracking that is found. That service bulletin also describes procedures for modifying the ESB to increase the thickness of the upper and lower webs and to install new angles and intercostals. The procedures for the modification also include an eddy current inspection for damage (e.g., cracking) of the fastener holes in the flanges that attach the upper and lower forward angles to the upper and lower webs, and repair (oversizing the fastener holes to remove damage) if necessary. This modification, if accomplished, eliminates the need for the repetitive inspections described previously.

Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. TCCA classified this service bulletin as mandatory and issued Canadian airworthiness directive CF-2001-26R1, dated September 20, 2002, to ensure the continued airworthiness of these airplanes in Canada.

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 21.29) 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 TCCA, 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 Proposed 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, the proposed AD would require accomplishment of the repetitive inspections specified in the service bulletin described previously, except as discussed below. The proposed AD also provides for accomplishing the modification specified in the service bulletin described previously, as an optional terminating action for the repetitive inspections. The actions would be required to be accomplished in accordance with the service bulletin described previously, except as discussed below under the heading “Difference Between Proposed AD, Referenced Service Bulletin, and TCCA Airworthiness Directive.”

Consistent with the findings of TCCA, the proposed AD would allow repetitive inspections per Part A of the Accomplishment Instructions of the service bulletin to continue in lieu of requiring accomplishment of the terminating action per Part B of the Accomplishment Instructions of the service bulletin. In making this determination, we considered that long-term continued operational safety in this case will be adequately ensured by repetitive inspections to detect any cracking of the upper and lower web of the ESB at FS 640 before such cracking represents a hazard to the airplane.

Difference Between Proposed AD, Referenced Service Bulletin, and TCCA Airworthiness Directive

Although the Canadian airworthiness directive specifies that it applies to airplanes having serial numbers 7003 through 7067 inclusive, 7069 through 7208 inclusive, 7210 through 7759 inclusive, and 7761 through 7782 inclusive; this proposed AD would apply to airplanes having serial numbers 7003 through 7067 inclusive, and 7069 through 7782 inclusive. This applicability matches the effectivity listing of Revision “D” of the service bulletin.

Although the service bulletin and the Canadian airworthiness directive specify that operators may contact the manufacturer for disposition of certain repair conditions, this proposed AD would require operators to repair those conditions per a method approved by either the FAA or TCCA (or its delegated agent). In light of the type of repair that would be required to address the unsafe condition, and consistent with existing bilateral airworthiness agreements, we have determined that, for this proposed AD, a repair approved by either the FAA or TCCA would be acceptable for compliance with this proposed AD.

Operators also should note that the Accomplishment Instructions of the referenced service bulletin describe procedures for completing a comment sheet related to service bulletin quality, a sheet recording compliance with the service bulletin, and an inspection results reporting form (located in Appendix A of the service bulletin). The Canadian airworthiness directive also specifies to report inspection results to the airplane manufacturer. This proposed AD would not require those actions. We do not need this information from operators.

Cost Impact

We estimate that 150 airplanes of U.S. registry would be affected by this proposed AD.

It would take approximately 1 work hour per airplane to accomplish the proposed inspection, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of the proposed inspection on U.S. operators is estimated to be $9,750, or $65 per airplane, per inspection cycle.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

The optional terminating action, if done, would take approximately 290 work hours, at an average labor rate of $65 per work hour. Required parts would be provided by the manufacturer at no charge. Based on these figures, we estimate the cost of the optional terminating action to be $18,850 per airplane.

Regulatory Impact

The regulations proposed herein would 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 proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting 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

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.