E6-19539. Airworthiness Directives; Bombardier Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), 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) airplanes, CL-600-2A12 (CL-601) airplanes, and CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604) airplanes. This proposed AD would require inspecting to identify the part number and serial number of the selector valves of the nose landing gear (NLG) and the nose gear door; and doing related investigative and corrective actions if necessary. This proposed AD results from reports of uncommanded partial retractions of the NLG. We are proposing this AD to prevent internal leakage of the selector valve, which, under certain conditions, could result in an uncommanded retraction of the NLG with consequent damage to the airplane and possible serious injury to ground personnel.

DATES:

We must receive comments on this proposed AD by December 20, 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-2006-26353; Directorate Identifier 2006-NM-189-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 certain 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. TCCA reports several cases of uncommanded retraction of the nose landing gear (NLG) of Model CL-600-2B19 airplanes caused by discrepant selector valves; the same selector valves may be installed on the airplanes identified in this proposed AD. (Further rulemaking will address the unsafe condition in Model CL-600-2B19 airplanes.) Investigation revealed that the end caps of certain NLG and nose gear door selector valves may have been incorrectly lock-wired or improperly torqued during manufacture. This could allow the valve end cap to back off and damage the valve seal, resulting in internal leakage of the valve. Such internal leakage, under certain conditions, could result in an uncommanded retraction of the NLG with consequent damage to the airplane and possible serious injury to ground personnel. Certain conditions involve the transfer or removal of electrical power from the airplane on the ground before the NLG safety pin is installed, when any pressure, including residual pressure, is present in the No. 3 hydraulic system.

Operators should be aware that selector valves having Bombardier P/N 601R75146-1, which are the subject of this proposed AD, may be supplied by different manufacturers and have different manufacturer part numbers. Only selector valves manufactured by Tactair Fluid Controls, having P/N 750006000, would be affected by this proposed AD.

Relevant Service Information

Bombardier has issued the service bulletins identified in the following table.

Bombardier Service Bulletins

Service Bulletin	Revision level	Date
600-0721 (for Model CL-600-1A11 (CL-600) airplanes)	01	February 20, 2006.
601-0558 (for Model CL-600-2A12 (CL-601), CL-600-2B16 (CL-601-3A and CL-601-3R) airplanes)	01	February 20, 2006.
604-32-021 (for Model CL-600-2B16 (CL-604) airplanes)	01	February 20, 2006.

The service bulletins describe procedures for inspecting for certain S/Ns of the selector valves of the NLG and the nose gear door, and doing related investigative and corrective actions if necessary. Related investigative actions include checking for proper installation of the lock wire of the end cap and verifying the torqued value of the end cap. Corrective actions include ensuring that any selector valve that has a properly installed lock wire and properly torqued end cap is marked with a new manufacturer part number and replacing any discrepant selector valve with a new or serviceable selector valve marked with the correct part number. 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-2006-16, dated July 6, 2006, to ensure the continued airworthiness of these airplanes in Canada.

The Bombardier service bulletins refer to Tactair Fluid Controls Service Bulletin SB750006000-1, Revision A, dated September 6, 2005, as an additional source of service information for doing the related investigative and corrective actions previously described.

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.

Clarification of Inspection Terminology

The service bulletins specify checking for proper installation of the lock wire; however, we have determined that this check should be a “general visual” inspection. We have included a definition of this type of inspection in Note 2 of this proposed AD.

Costs of Compliance

This proposed AD would affect about 492 airplanes of U.S. registry.

The inspection to determine the manufacturer P/N and S/N of the selector valve(s) 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 $39,360, or $80 per airplane.

The general visual inspection of the selector valve(s), if accomplished, 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 $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-2006-26353; Directorate Identifier 2006-NM-189-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by December 20, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model CL-600-1A11 (CL-600) airplanes, CL-600-2A12 (CL-601) airplanes, and CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604) airplanes; certificated in any category; having serial numbers (S/Ns) as identified in the service bulletins specified in Table 1 of this AD, as applicable.

Table 1.—Bombardier Service Bulletins

Service Bulletin	Revision level	Date
600-0721 (for Model CL-600-1A11 (CL-600) airplanes)	01	February 20, 2006.
601-0558 (for Model CL-600-2A12 (CL-601) airplanes, and CL-600-2B16 (CL-601-3A and CL-601-3R) airplanes)	01	February 20, 2006.
604-32-021 (for Model CL-600-2B16 (CL-604) airplanes)	01	February 20, 2006.

Unsafe Condition

(d) This AD results from reports of uncommanded partial retractions of the nose landing gear (NLG). We are issuing this AD to prevent internal leakage of the selector valve, which, under certain conditions, could result in an uncommanded retraction of the NLG with consequent damage to the airplane and possible serious injury to ground personnel.

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.

Inspection and Corrective Actions

(f) Within 500 flight hours or 12 months after the effective date of this AD, whichever occurs first, inspect to determine the manufacturer part number (P/N) and S/N of the selector valves of the NLG and nose gear door. A review of airplane maintenance records is acceptable in lieu of this inspection if the S/Ns of the selector valves can be conclusively determined from that review. For any subject selector valve having Tactair Fluid Controls P/N 750006000 and a S/N from 0001 through 0767 inclusive, before further flight, do related investigative (including a general visual inspection for proper installation of the lock wire of the end cap) and corrective actions; in accordance with the applicable service bulletins identified in Table 1 of this AD.

Note 1:

Operators should be aware that selector valves having Bombardier P/N 601R75146-1 may be supplied by different manufacturers and have different manufacturer part numbers. Only airplanes having selector valves manufactured by Tactair Fluid Controls, having P/N 750006000, are subject to the investigative and corrective actions specified in paragraph (f) of this AD.

Note 2:

For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

Note 3:

The service bulletins identified in Table 1 of this AD refer to Tactair Fluid Controls Service Bulletin SB750006000-1, Revision A, dated September 6, 2005, as an additional source of service information for doing the related investigative and corrective actions required by this AD.

Parts Installation

(g) As of the effective date of this AD, no person may install on any airplane a subject selector valve having a S/N from 0001 through 0767 inclusive, unless that selector valve meets the requirements of paragraph (f) of this AD.

Alternative Methods of Compliance (AMOCs)

(h)(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

(i) Canadian airworthiness directive CF-2006-16, dated July 6, 2006, also addresses the subject of this AD.

Issued in Renton, Washington, on November 8, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.