06-4847. Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This AD requires revising the Airworthiness Limitations section of the Instructions for Continuing Airworthiness of the Maintenance Requirements Manual to include revised threshold and repeat inspection intervals for the cargo door skin cut-out. This AD results from a report that a crack was discovered at the lower forward corner of a cargo door skin cut-out during fatigue testing. We are issuing this AD to detect and correct cracking in the lower forward corner of the cargo door skin cut-out, which could result in reduced structural integrity of the airplane.

DATES:

This AD becomes effective June 30, 2006.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of June 30, 2006.

ADDRESSES:

You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, Room PL-401, Washington, DC.

Contact Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT:

Richard Beckwith, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, suite 410, Westbury, New York 11590; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Examining the Docket

You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. That NPRM was published in the Federal Register on February 9, 2006 (71 FR 6683). That NPRM proposed to require revising the Airworthiness Limitations section of the Instructions for Continuing Airworthiness of the Maintenance Requirements Manual to include revised threshold and repeat inspection intervals for the cargo door skin cut-out.

Comments

We provided the public the opportunity to participate in the development of this AD. We have considered the comment received.

Request To Change Applicability

Air Wisconsin notes that the applicability of the proposed AD includes airplanes with serial numbers 7003 and subsequent on which Bombardier Modsum TC601R16421 or TC601R16422 has not been accomplished. Air Wisconsin also notes that Modsums cannot be accomplished on in-service airplanes because in-service airplanes are modified per service bulletins, in this case Bombardier Service Bulletin 601R-53-070. Air Wisconsin states that Bombardier Service Bulletin 601R-53-070 will be released very soon to communicate in-service Modsum TC601R16422; and that the actions in that service bulletin will be terminating action for in-service airplanes. This will limit the applicability to serial number 7003 to 8129 because production Modsum TC601R16421 will be accomplished on serial number 8130 and subsequent.

We infer that Air Wisconsin is requesting that we change the applicability of the proposed AD to include a reference to Bombardier Service Bulletin 601R-53-070, and to limit the affected serial numbers to 7003 through 8129 inclusive. We disagree. There may be production delays that would result in a change to those airplanes on which production Modsum TC601R16421 is accomplished in production. In addition, Bombardier Service Bulletin 601R-53-070 has not been released by Bombardier, and we cannot refer to a document that is not yet released and approved. The actions in this AD are not required if one of the Modsums has been accomplished on an airplane. Bombardier can provide methods for showing that a Modsum has been accomplished. Also, an operator may request an alternative method of compliance in accordance with the procedures in paragraph (g) of this AD. We have not changed the AD in this regard.

Conclusion

We have carefully reviewed the available data, including the comment received, and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

The following table provides the estimated costs for U.S. operators to comply with this AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
AWL Revision	1	$65	$65	738	$47,970

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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.

For the reasons discussed above, I certify that this AD:

(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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

2006-11-09 Bombardier, Inc. (Formerly Canadair): Amendment 39-14613. Docket No. FAA-2006-23841; Directorate Identifier 2005-NM-214-AD.

Effective Date

(a) This AD becomes effective June 30, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, serial numbers 7003 and subsequent, certificated in any category; on which Bombardier Modsum TC601R16421 or TC601R16422 has not been accomplished.

Unsafe Condition

(d) This AD results from a report that a crack was discovered at the lower forward corner of a cargo door skin cut-out during fatigue testing. We are issuing this AD to detect and correct cracking in the lower forward corner of the cargo door skin cut-out, which could result in reduced structural integrity of the airplane

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

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 according to the procedures specified in paragraph (g) of this AD. 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.

Maintenance Requirements Manual Revision

(f) Within 30 days after the effective date of this AD, revise the Airworthiness Limitations (AWL) section (Appendix B) of the Instructions for Continuing Airworthiness of the Canadair Regional Jet Maintenance Requirements Manual (MRM), to include the information specified in AWL Task 53-61-141 in Canadair Regional Jet Temporary Revision (TR) 2B-2109, dated October 13, 2005. Thereafter, except as provided by paragraph (g) of this AD, no alternative structural inspection intervals may be approved for the cargo door skin cut-out.

Note 2:

The actions required by paragraph (f) of this AD may be done by inserting a copy of TR 2B-2109 into the AWL section of the Canadair Regional Jet MRM. When the contents of TR have been included in general revisions of the MRM, the general revisions may be inserted in the MRM, provided the relevant information in the general revision is identical to that in TR 2B-2109.

Alternative Methods of Compliance (AMOCs)

(g)(1) The Manager, New York Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(h) Canadian airworthiness directive CF-2005-05, dated February 18, 2005, also addresses the subject of this AD.

Material Incorporated by Reference

(i) You must use Canadair Regional Jet Temporary Revision 2B-2109, dated October 13, 2005, Part 2, Appendix B of the Canadair Regional Jet Maintenance Requirements Manual to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Bombardier, Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville, Montreal, Quebec H3C 3G9, Canada, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov;​; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call [phone], or go to http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on May 16, 2006.

Kevin M. Mullin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.