AD 2010-23-19

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Two cases of main landing gear (MLG) failure to fully extend have been reported. An MLG failing to extend may result in an unsafe asymmetric landing configuration.

Preliminary investigation has shown that interference between the MLG door and the MLG fairing seal prevented the MLG door from opening.

* * * * *

The unsafe condition is possible loss of controllability of the airplane during landing. This AD requires actions that are intended to address the unsafe condition described in the MCAI.

Final rule; request for comments.

2010-23-19 Bombardier, Inc.: Amendment 39-16508. Docket No. FAA- 2010-1106; Directorate Identifier 2010-NM-237-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective November 24, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to the Bombardier, Inc. airplanes identified in paragraphs (c)(1) and (c)(2) of this AD, certificated in any category.

(1) Model CL-600-2C10 (Regional Jet Series 700, 701, & 702) airplanes, having serial numbers (S/Ns) 10003 and subsequent.

(2) Model CL-600-2D15 (Regional Jet Series 705) and CL-600-2D24 (Regional Jet Series 900) airplanes, having S/Ns 15001 and subsequent.

Subject

(d) Air Transport Association (ATA) of America Code 32: Landing gear.

Reason

(e) The mandatory continued airworthiness information (MCAI) states:

Two cases of main landing gear (MLG) failure to fully extend have been reported. An MLG failing to extend may result in an unsafe asymmetric landing configuration.

Preliminary investigation has shown that interference between the MLG door and the MLG fairing seal prevented the MLG door from opening.

* * * * *

The unsafe condition is possible loss of controllability of the airplane during landing.

Compliance

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

Repetitive Inspections and Corrective Actions

(g) For airplanes having S/Ns 10003 to 10313 inclusive, 15001 to 15238 inclusive, and 15240 to 15255 inclusive: Within 50 flight cycles after the effective date of this AD, do the inspections specified in paragraphs (g)(1), (g)(2), (g)(3), and (g)(4) of this AD, in accordance with "PART A--Inspection of the MLG Inboard Doors, MLG Fairing and Adjacent Structure'' of the Accomplishment Instructions of Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010. Repeat theinspections thereafter at intervals not to exceed 600 flight hours.

(1) Do a detailed inspection for damage (including wear lines, cracks, fraying, tears, and evidence of chafing) of the rubber seal of the MLG fairing.

(2) Do a detailed inspection for damage (including missing and broken rollers, loose and missing fasteners, damaged and missing stops) of the MLG inboard doors, and damage along the edge of the MLG inboard door adjacent to the MLG fairing.

(3) Do a detailed inspection of the MLG fairing for damage (including missing forward and aft stops, loose and missing fasteners), and damage along the edge of the MLG fairing adjacent to the MLG door.

(4) Do a detailed inspection for damage (including missing stops, loose and missing fasteners, and missing wedges) of the stops and wedge on the forward and aft spars.

(h) For airplanes not identified in paragraph (g) of this AD: Within 600 flight hours after the effective date of this AD, do the inspections specified in paragraphs (h)(1), (h)(2), (h)(3), and (h)(4) of this AD, in accordance with "PART A--Inspection of the MLG Inboard Doors, MLG Fairing and Adjacent Structure'' of the Accomplishment Instructions of Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010. Repeat the inspections thereafter at intervals not to exceed 600 flight hours.

(1) Do a detailed inspection for damage (including wear lines, cracks, fraying, tears, and evidence of chafing) of the rubber seal of the MLG fairing.

(2) Do a detailed inspection for damage (including missing and broken rollers, loose and missing fasteners, damaged and missing stops) of the MLG inboard doors, and damage along the edge of the MLG inboard door adjacent to the MLG fairing.

(3) Do a detailed inspection of the MLG fairing for damage (including missing forward and aft stops, loose and missing fasteners), and damage along the edge of the MLG fairing adjacent to the MLG door.

(4) Do a detailed inspection for damage (including missing stops, loose and missing fasteners, and missing wedges) of the stops and wedge on the forward and aft spars.

(i) If damage to only the rubber seal on the MLG fairing is found during any inspection required by paragraph (g) or (h) of this AD: Before further flight, do either action in paragraph (i)(1) or (i)(2) of this AD.

(1) Replace the rubber seal on the MLG fairing with a new rubber seal, in accordance with "PART B--Replacement of the Forward Rubber Seal on the MLG Fairing'' of the Accomplishment Instructions of Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010.

(2) Remove the MLG inboard door, in accordance with "PART C-- Removal of MLG Inboard Door'' of the Accomplishment Instructions of Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010. For airplanes on which the MLG inboard door is re- installed, do the installation of the MLG inboard door in accordance with "PART D--Installation of MLG Inboard Door'' of the Accomplishment Instructions of Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010.

(j) If damage other than the damage identified in paragraph (i) of this AD is found during any inspection required by paragraph (g) or (h) of this AD: Before further flight, contact the Bombardier Regional Aircraft Customer Response Center for repair instructions and do the repair.

(k) Submit a report of the positive findings of the initial inspection required by paragraph (g) or (h), as applicable, of this AD to Bombardier, at the applicable time specified in paragraph (k)(1) or (k)(2) of this AD. The report must include the information specified in Appendix A of Bombardier Alert Service Bulletin A670BA- 32-030, Revision A, dated October 22, 2010.

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

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

Credit for Actions Accomplished in Accordance With Previous Service Information

(l) Actions accomplished before the effective date of this AD according to Bombardier Alert Service Bulletin A670BA-32-030, dated October 18, 2010, are considered acceptable for compliance with the corresponding action specified in this AD.

FAA AD Differences

Note 1: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(m) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, New York ACO, ANE-170, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone 516-228-7300; fax 516-794-5531. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements andhas assigned OMB Control Number 2120-0056.

Related Information

(n) Refer to MCAI Canadian Airworthiness Directive CF-2010-36, dated October 18, 2010; and Bombardier Alert Service Bulletin A670BA-32-030, Revision A, dated October 22, 2010; for related information.

Material Incorporated by Reference

(o) You must use Bombardier Alert Service Bulletin A670BA-32- 030, Revision A, including Appendix A, dated October 22, 2010, to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Bombardier, Inc., 400 C te-Vertu Road West, Dorval, Qu bec H4S 1Y9, Canada; telephone 514-855-5000; fax 514-855- 7401; e-mail thd.crj@aero.bombardier.com; Internet http:// www.bombardier.com.

(3) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

(4) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http:// www.archives.gov/federal_register/code_of_federal_regulations/ ibr_locations.html.

Discussion

Transport Canada Civil Aviation, which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF-2010-36, dated October 18, 2010 (referred to after this as "the MCAI''), to correct an unsafe condition for the specified products. The MCAI states:

Two cases of main landing gear (MLG) failure to fully extend have been reported. An MLG failing to extend may result in an unsafe asymmetric landing configuration.

Preliminary investigation has shown that interference between the MLG door and the MLG fairing seal prevented the MLG door from opening.

This [Canadian airworthiness] directive mandates [repetitive detailed] inspection[s for damage] and rectification, as required, of the MLG fairing and seal, MLG door, and adjacent structures.

The unsafe condition is possible loss of controllability of the airplane during landing. Damage includes the following:

Wear lines, cracks, fraying, tears, and evidence of chafing of the rubber seal of the MLG fairing;

Missing and broken rollers, loose and missing fasteners, and damaged and missing stops of the MLG inboard doors; and damage along the edge of the MLG inboard door adjacent to the MLG fairing;

Missing forward and aft stops, loose and missing fasteners of the MLG fairing; and damage along the edge of the MLG fairing adjacent to the MLG door; and

Missing stops, loose and missing fasteners, and missing wedges of the stops and wedge on the forward and aft spars.

Rectification (i.e., corrective actions) includes replacing the rubber seal or removing the MLG inboard door, and contacting Bombardier for repair instructions and doing the repair. You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Bombardier has issued Alert Service Bulletin A670BA-32-030, Revision A, including Appendix A, dated October 22, 2010. The actions described in this service informationare intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

Differences Between the AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a NOTE within the AD.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because the main landing gear may fail to extend, which could result in an asymmetric landing configuration. Therefore, we determined that notice and opportunity for public comment before issuing this AD are impracticable and that good cause exists for making this amendment effective in fewer than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment.We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include "Docket No. FAA-2010-1106; Directorate Identifier 2010-NM-237-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments.

We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD.

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 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 this AD: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. 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.

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.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by adding thefollowing new AD: