E6-14941. Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for all Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This proposed AD would require revising the Certification Maintenance Requirements and the Maintenance Review Board Report sections of the Canadair Regional Jet Maintenance Requirements Manual to include changes and additions to checks of the aileron power control units (PCUs) and a change to the interval of the backlash check of the aileron control system. This proposed AD results from a report that data collected from in-service airplanes show that approximately 19 percent of aileron backlash checks conducted at 4,000-flight-hour intervals reveal that aileron backlash wear limits are being exceeded. We are proposing this AD to prevent exceeded backlashes in both aileron PCUs, which, if accompanied by the failure of the flutter damper, could result in aileron vibration/flutter and reduced controllability of the airplane.

DATES:

We must receive comments on this proposed AD by October 11, 2006.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401, Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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

FOR FURTHER INFORMATION CONTACT:

Daniel Parrillo, Aerospace Engineer, Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “FAA-2006-25779; Directorate Identifier 2006-NM-088-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the 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 DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, notified us that an unsafe condition may exist on all Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. TCCA advises that data collected from in-service airplanes show that approximately 19 percent of aileron backlash checks conducted at 4,000-flight-hour intervals reveal that aileron backlash wear limits are being exceeded. Exceeding the backlash in both aileron power control units (PCUs), if accompanied by the failure of the flutter damper, could result in aileron vibration/flutter and reduced controllability of the airplane.

Relevant Service Information

Bombardier has issued Canadair Regional Jet Temporary Revision 2A-20, dated March 13, 2006, to Part 2, Appendix A—Certification Maintenance Requirements, of the Canadair Regional Jet Maintenance Requirements Manual (MRM), CSP A-053. The temporary revision adds Task C27-10-105-06, a functional check of each aileron PCU for internal leakage at intervals not to exceed 5,000 flight hours, and revises Task C27-10-105-05 to remove the check of the aileron PCU from the functional check of each rudder and elevator PCU for backlash and deflection under load at intervals not to exceed 4,000 flight hours.

Bombardier has also issued Canadair Regional Jet Temporary Revision 1-2-33, dated October 27, 2005, to Part 1, Section 2—Systems/Powerplant Program, of the Canadair Regional Jet MRM, CSP A-053. The temporary revision revises Task 27-11-00-09 to perform the functional check (backlash) of the aileron control system at intervals not to exceed 2,000 flight hours.

Bombardier also issued Revision 10, dated May 27, 2005, of the Canadair Regional Jet Maintenance Review Board (MRB) Report for Section 2—Systems and Powerplant Program, of Part 1 of the Canadair Regional Jet MRM, CSP A-053. Revision 10 incorporates Task 27-11-00-09 as revised by Canadair Regional Jet Temporary Revision 1-2-33, into the MRB report.

TCCA mandated the service information and issued Canadian airworthiness directive CF-2006-04, dated March 22, 2006, to ensure the continued airworthiness of these airplanes in Canada.

FAA's Determination and Requirements of the Proposed AD

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. We have examined TCCA's findings, evaluated all pertinent information, and determined that we need to issue an AD for airplanes of this type design that are certificated for operation in the United States.

Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

This proposed AD would affect about 742 airplanes of U.S. registry. The proposed actions would take about 1 work hour per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $59,360, or $80 per airplane.

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 proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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 proposed 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
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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):

Bombardier, Inc. (Formerly Canadair): Docket No. FAA-2006-25779; Directorate Identifier 2006-NM-088-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by October 11, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from a report that data collected from in-service airplanes show that approximately 19 percent of aileron backlash checks conducted at 4,000-flight-hour intervals reveal that aileron backlash wear limits are being exceeded. We are issuing this AD to prevent exceeded backlashes in both aileron power control units (PCUs), which, if accompanied by the failure of the flutter damper, could result in aileron vibration/flutter and reduced controllability 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.

Revision of the Maintenance Requirements Manual (MRM)

(f) Within 60 days after the effective date of this AD, revise the Canadair Regional Jet MRM CSP A-053 by doing the actions specified in paragraphs (f)(1) and (f)(2) of this AD. When the tasks specified in Canadair Regional Jet Temporary Revisions 2A-20, dated March 13, 2006; and 1-2-33, dated October 27, 2005; are included in the general revisions of the MRM, the general revisions may be inserted in the MRM, and these temporary revisions may be removed.

(1) Revise the Certification Maintenance Requirements section of the Canadair Regional Jet MRM to include Tasks C27-10-105-06 and C27-10-105-05, as specified in Canadair Regional Jet Temporary Revision 2A-20, dated March 13, 2006, to Part 2, Appendix A—Certification Maintenance Requirements, of the Canadair Regional Jet MRM CSP A-053.

(2) Revise the Maintenance Review Board Report for Section 2—Systems and Powerplant Program, of Part 1 of the Canadair Regional Jet MRM CSP A-053, to include the task interval for Task 27-11-00-09, as specified in Canadair Regional Jet Temporary Revision 1-2-33, dated October 27, 2005. Incorporating Revision 10, dated May 27, 2005, of the Canadair Regional Jet Maintenance Review Board Report for Section 2—Systems and Powerplant Program of the Canadair Regional Jet MRM CSP A-053 is one approved method for including the task interval specified in Canadair Regional Jet Temporary Revision 1-2-33. After the task interval has been incorporated into the MRM, no alternative aileron backlash check interval in excess of 2,000 flight hours may be approved, except as specified in paragraphs (g) and (h) of this AD.

Phase-In Schedule for Initial Inspection Specified in MRM Revisions

(g) For airplanes with more than 1,000 flight hours but less than 3,000 flight hours since the last aileron backlash check specified in Task 27-11-00-09 was accomplished, as of the effective date of this AD: Within 1,000 flight hours after the effective date of this AD, do the next aileron backlash check in accordance with Task 27-11-00-09, as specified in Canadair Regional Jet Temporary Revision 1-2-33, dated October 27, 2005.

(h) For airplanes with 3,000 flight hours or more since the last aileron backlash check specified in Task 27-11-00-09 was accomplished, as of the effective date of this AD: Within 4,000 flight hours since the last aileron backlash check, do the next aileron backlash check in accordance with Task 27-11-00-09, as specified in Canadair Regional Jet Temporary Revision 1-2-33, dated October 27, 2005.

One Approved Method for Task C27-10-105-06

(i) For airplanes without access to ground support equipment necessary to do the PCU internal leakage functional check as specified in Task C27-10-105-06 as specified in paragraph (f)(1) of this AD: Doing the aileron PCU internal leakage check in accordance with Task 27-11-00-220-803 of Chapter 27-11-00 of the Canadair Regional Jet Aircraft Maintenance Manual at intervals not to exceed 4,000 flight hours is one approved method for accomplishing Task C27-10-105-06 and is acceptable for up to 12 months after the effective date of this AD. Thereafter, the check must be done in accordance with Task C27-10-105-06 as specified in paragraph (f)(1) of this AD at a repetitive interval not to exceed that specified in the task.

Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, New York Aircraft Certification Office, 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

(k) Canadian airworthiness directive CF-2006-04, dated March 22, 2006, also addresses the subject of this AD.

Issued in Renton, Washington, on September 1, 2006.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.