Airworthiness Directives; Bombardier Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604) 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 certain Bombardier Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16 (CL-601-3A, CL-601-3R, & CL-604) airplanes. This proposed AD would require modifying the rudder balance spring assembly by installing a new adjustable balance spring, and rigging the assembly to suit the rudder of each airplane. This proposed AD results from production inspections that showed that the spring assembly that controls rudder balance may not have the correct pre-load on some airplanes. We are proposing this AD to prevent uncommanded yaw movements and consequent reduced controllability of the airplane.

DATES:

We must receive comments on this proposed AD by December 12, 2005.

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: (202) 493-2251.
• 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 (516) 228-7305; fax (516) 794-5531.

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-2005-22917; Directorate Identifier 2005-NM-157-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 9:00 a.m. and 5:00 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) 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 certain Bombardier Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16 (CL-601-3A, CL-601-3R, & CL-604) airplanes. TCCA advises that production inspections showed that the spring assembly that controls rudder balance may not have the correct pre-load on some airplanes. The spring assembly must be pre-loaded correctly so it can position the rudder close to its neutral position in case one of several linked components in the aft section of the rudder assembly disconnects during flight. If the rudder is not positioned close to neutral in this instance, excessive rudder deflections (side-to-side movements) may occur. In order to ensure that the rudder moves to neutral position and rudder deflections remain within acceptable limits, the balance spring assembly must be modified and rigged to suit the rudder of each airplane. No linked components in the aft section of the rudder assembly have disconnected in service; however, this condition, if not corrected, could result in uncommanded yaw movement and reduced controllability of the airplane.

Relevant Service Information

Bombardier has issued the service bulletins in the following table.

The service bulletins describe procedures for modifying the rudder balance spring assembly by installing a new adjustable balance spring; and rigging the adjustable rudder balance spring assembly by measuring, adjusting, and testing the deflection to be within the limits specified in the applicable service bulletin. If the deflection cannot be adjusted to be within acceptable limits defined in the service bulletins, the service bulletins specify that operators contact the manufacturer for further instructions.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. TCCA mandated the service information and issued Canadian airworthiness directive CF-2005-21, dated June 23, 2005, 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, except as discussed under “Difference Between Proposed AD, Service Bulletin 604-27-013, and Canadian Airworthiness Directive.”

Difference Between Proposed AD and Service Bulletins

The service bulletins specify that you contact the manufacturer for instructions on how to make certain adjustments, but this proposed AD would require you to make the adjustments using a method that we or TCCA approve.

Difference Among Proposed AD, Service Bulletin 604-27-013, and Canadian Airworthiness Directive

Although the Canadian airworthiness directive and Bombardier Service Bulletin 604-27-013 indicate that the actions proposed in this AD would apply to Model CL-600-2B16 (CL-604) airplanes, serial numbers (S/Ns) 5301 through 5584, this proposed AD would apply to S/Ns 5301 through 5564. Service Bulletin Information Sheet 604-27-013, dated January 30, 2004, indicates that Model CL-600-2B16 (CL-604) airplanes, S/Ns 5565 and subsequent, are scheduled to have this modification in production. Therefore, this proposed AD would not apply to Model CL-600-2B16 (CL-604) airplanes, S/Ns 5565 and subsequent.

The manufacturer is aware of this discrepancy, and concurs with the change. This difference has also been coordinated with TCCA.

Costs of Compliance

This proposed AD would affect about 501 airplanes of U.S. registry. The proposed actions would take about 12 work hours per airplane, at an average labor rate of $65 per work hour. Required parts would cost about $1,749 per airplane. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $1,267,029, or $2,529 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.