AD 2003-20-03

This amendment adopts a new airworthiness directive (AD), applicable to certain Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, that requires revising the airworthiness limitations section of the Instructions for Continued Airworthiness by incorporating new structural inspection intervals for the vertical beams of the pressure bulkheads at fuselage stations 409+128 and 559; repairing the vertical beams if necessary; and submitting inspection findings to the airplane manufacturer. This action is necessary to detect and correct, in a timely manner, fatigue cracks in the vertical beams of the pressure bulkheads at fuselage stations 409+128 and 559, which could result in the reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.

Final rule.

2003-20-03 Bombardier, Inc. (Formerly Canadair): Amendment 39-13321. Docket 2003-NM-143-AD.

Applicability: Model CL-600-2B19 (Regional Jet series 100 & 440) airplanes, serial numbers 7003 through 7999 inclusive; certificated in any category.

Note 1: This AD requires revisions to certain operator maintenance documents to include new inspections. Compliance with these inspections is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by these inspections, the operator may not be able to accomplish the inspections described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance from the office identified in paragraph (d) of this AD and Sections 39.19 and 39.21 of the Federal Aviation Regulations (14 CFR 39.19 and 39.21). The request should include a description of changes to the required inspections that will ensure the continued damage tolerance of the affected structure. The FAA has provided guidance for this determination in Advisory Circular (AC) 25-1529.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct, in a timely manner, fatigue cracks in the vertical beams of the pressure bulkheads at fuselage stations 409+128 and 559, which could result in the reduced structural integrity of the airplane, accomplish the following:

Revise Airworthiness Limitations (AWL) Section

(a) Within 14 days after the effective date of this AD, revise the AWL section of the Instructions for Continued Airworthiness by incorporating the contents of Canadair Temporary Revision (TR) 2B- 1566, dated January 31, 2003, to the Canadair Regional Jet Maintenance Requirements Manual, Part 2, Appendix B, "Airworthiness Limitations," into the AWL section. Thereafter, except as provided in paragraph (d) of this AD, no alternative structural inspection intervals may be approved for the vertical beams on the pressure bulkheads at fuselage stations 409+128 and 559.

Note 2: When the contents of TR 2B-1566 have been included in the general revisions of the AWL section, the general revisions may be incorporated into the AWL section, and the TR may be removed from the AWL section.

Repair and Revise AWL Section

(b) If any crack is found during any inspection done according to the AWL section of the Instructions for Continued Airworthiness specified in paragraph (a) of this AD, do the actions specified in paragraphs (b)(1) and (b)(2) of this AD.

(1) Before further flight: Repair per a method approved by either the Manager, New York Aircraft Certification Office (ACO), FAA; or Transport Canada Civil Aviation (TCCA) (or its delegated agent).

(2) Within 14 days after receiving the new AWL associated with a repair: Revise the AWL section of the Instructions for Continued Airworthiness by inserting a copy of the new airworthiness limitation and inspection requirements associated with the FAA- or TCCA-approved repair referred to in paragraph (b)(1) of this AD into the Canadair Regional Jet Maintenance Requirements Manual, Part 2, Appendix B, "Airworthiness Limitations" section. Thereafter, except as provided in paragraph (d) of this AD, no alternative structural inspection intervals specified in the FAA- or TCCA- approved repair may be approved for the vertical beams on the pressure bulkheads at fuselage stations 409+128 and 559.

Reporting

(c) Submit a report of the findings (both positive and negative) of the inspection required by paragraph (a) of this AD to Bombardier, Inc., Canadair, Aerospace Group, CRJ Technical Help Desk, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada; fax (514) 855-8501; at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD. Information collection requirements contained in this AD have been approved by the Office of Management and Budget (OMB) under the provision of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(1) If the inspection was done after the effective date of this AD: Submit the report within 30 days after the inspection.

(2) If the inspection was done prior to the effective date of this AD: Submit the report within 30 days after the effective date of this AD.

Alternative Methods of Compliance

(d) In accordance with 14 CFR 39.19, the Manager, New York ACO, FAA, is authorized to approve alternative methods of compliance for this AD.

Incorporation by Reference

(e) Unless otherwise specified in this AD, the actions shall be done in accordance with Canadair Temporary Revision 2B-1566, dated January 31, 2003, to the Canadair Regional Jet Maintenance Requirements Manual, Part 2, Appendix B, "Airworthiness Limitations." 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 Centre-ville, 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, 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-2003-08, dated April 23, 2003.

Effective Date

(f) This amendment becomes effective on November 10, 2003.

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- 2B19 (Regional Jet Series 100 & 440) airplanes was published in the Federal Register on July 9, 2003 (68 FR 40829). That action proposed to require revising the airworthiness limitations section of the Instructions for Continued Airworthiness by incorporating new structural inspection intervals for the vertical beams of the pressure bulkheads at fuselage stations 409+128 and 559; repairing the vertical beams if necessary; and submitting inspection findings to the airplane manufacturer.

Comments

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.

Conclusion

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

Interim Action

This is considered to be interim action. The inspection reports required by this AD will enable the manufacturer to obtain better insight into the cause of the fatigue cracks in the vertical beams of the pressure bulkheads at fuselage stations 409+128 and 559. Once final action has been identified, the FAA may consider further rulemaking.

Cost Impact

The FAA estimates that 533 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 labor rate is $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $34,645, or $65 per airplane.

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 inthe 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.

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.

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: