E6-14617. Airworthiness Directives; Bombardier Model CL-600-2B16 (CL-604) Airplanes and Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes

AGENCY:

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

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model CL-600-2B16 (CL-604) airplanes and Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. These models may be referred to by their marketing designations as RJ100, RJ200, CRJ100, CRJ200, and CL-65. This AD requires revising the Emergency Procedures section of the airplane flight manual (AFM) to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway. For certain airplanes, this AD also requires revising the Abnormal Procedures section of the AFM to advise the flightcrew of procedures to follow in the event of MACH TRIM, STAB TRIM, and horizontal stabilizer trim malfunctions. This AD results from reports of uncommanded horizontal stabilizer trim motion. We are issuing this AD to ensure that the flightcrew is advised of appropriate procedures to follow in the event of stabilizer trim runaway. Failure to follow these procedures could result in excessive uncommanded movement of the horizontal stabilizer trim actuator (HSTA) and loss of ability to use trim switches to override uncommanded movement or yoke disconnect switches to disconnect the HSTA, which could result in reduction of or loss of pitch trim control and consequent reduced controllability of the airplane.

DATES:

This AD becomes effective September 1, 2006.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the AD as of September 1, 2006.

We must receive comments on this AD by October 31, 2006.

ADDRESSES:

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

FOR FURTHER INFORMATION CONTACT:

Bruce Valentine, 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:

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-600-2B16 (CL-604) airplanes and Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. TCAA advises that there have been reports of uncommanded horizontal stabilizer trim motion on Model CL-600-2B16 (CL-604) airplanes. Investigation revealed contamination of the circuit board of the horizontal stabilizer trim control unit (HSTCU). The circuit boards installed on HSTCUs were not conformal coated to protect against moisture exposure. Contamination of the circuit board could lead to one or more of the following types of behavior:

• Erratic/intermittent uncommanded movement of the horizontal stabilizer trim actuator (HSTA).
• Uncommanded movement of the HSTA to the full up or full down position.
• Loss of the flightcrew's ability to override uncommanded movement by use of the trim switches.
• Loss of the flightcrew's ability to disconnect the HSTA using the yoke disconnect switches.

These conditions, if not corrected, could result in reduction of or loss of pitch trim control and consequent reduced controllability of the airplane.

The HSTCU circuit boards on Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes are identical to that on the affected Model CL-600-2B16 (CL-604) airplanes. Therefore, those Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes may be subject to the unsafe condition revealed on the Model CL-600-2B16 (CL-604) airplanes.

Relevant Service Information

Canadair (Bombardier) has issued the temporary revisions (TRs) specified in the table below.

 Table—TRs

For Bombardier model—	Use—	Dated—	To the—
CL-600-2B16 (CL-604) airplanes	Canadair Challenger TR 604/21	August 1, 2006	Canadair Challenger CL-604 AFM, PSP 604-1.
CL-600-2B19 (Regional Jet Series 100 & 440) airplanes	Canadair Regional Jet TR RJ/152-4	August 9, 2006	Canadair Regional Jet AFM, CSP A-012.

TR 604/21 describes revising the Emergency Procedures section of the airplane flight manual (AFM) to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway. TR RJ/152-4 describes revising the Emergency and Abnormal Procedures sections of the AFM to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway and to advise the flightcrew of procedures to follow in the event of MACH TRIM, STAB TRIM, and horizontal stabilizer trim malfunctions.

TCCA mandated the service information and issued Canadian airworthiness directives CF-2006-20, dated August 22, 2006, and CF-2006-21, dated August 23, 2006, to ensure the continued airworthiness of these airplanes in Canada.

FAA's Determination and Requirements of This 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 products of this type design that are certificated for operation in the United States.

Therefore, we are issuing this AD to ensure that the flightcrew is advised of appropriate procedures to follow in the event of stabilizer trim runaway. Failure to follow these procedures could result in excessive uncommanded movement of the HSTA and loss of ability to use trim switches to override uncommanded movement or yoke disconnect switches to disconnect the HSTA, which could result in reduction of or loss of pitch trim control and consequent reduced controllability of the airplane. This AD requires revising the Emergency and Abnormal Procedures sections, as applicable, of the AFM to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway. This AD follows the Canadian airworthiness directives referred to previously and adopts the same requirements.

Interim Action

We consider this AD interim action. The manufacturer is currently developing service bulletins that specify replacing HSTCU circuit boards with HSTCU circuit boards having conformal coating and is exploring other interim measures that will address the identified unsafe condition specified in this AD. Once new service information is developed, approved, and available, we may consider additional rulemaking.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD; therefore, providing notice and opportunity for public comment before the AD is issued is impracticable, and good cause exists to make this AD effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any relevant written data, views, or arguments regarding this AD. Send your comments to an address listed in the ADDRESSES section. Include “Docket No. FAA-2006-25724; Directorate Identifier 2006-NM-197-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD that might suggest a need to modify it.

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 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.

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 the 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 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):

2006-18-04 Bombardier, Inc. (Formerly Canadair): Amendment 39-14742. Docket No. FAA-2006-25724; Directorate Identifier 2006-NM-197-AD.

Effective Date

(a) This AD becomes effective September 1, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model CL-600-2B16 (CL-604) airplanes, serial numbers 5301 and subsequent; and Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, serial numbers 7003 through 7990 inclusive and 8000 and subsequent; certificated in any category.

Note 1:

The Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes may be referred to by their marketing designations as RJ100, RJ200, CRJ100, CRJ200, and CL-65.

Unsafe Condition

(d) This AD results from reports of uncommanded horizontal stabilizer trim motion. We are issuing this AD to ensure that the flightcrew is advised of appropriate procedures to follow in the event of stabilizer trim runaway. Failure to follow these procedures could result in excessive uncommanded movement of the horizontal stabilizer trim actuator (HSTA) and loss of ability to use trim switches to override uncommanded movement or yoke disconnect switches to disconnect the HSTA, which could result in reduction of or loss of pitch trim control and consequent 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.

Airplane Flight Manual (AFM) Revision

(f) Within 7 days after the effective date of this AD, make the applicable AFM revisions specified in paragraph (f)(1) or (f)(2) of this AD by incorporating the applicable Canadair (Bombardier) temporary revisions (TRs) identified in Table 1 of this AD into the applicable AFM.

(1) For Model CL-600-2B16 (CL-604) airplanes: Revise the Emergency Procedures section of the AFM to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway.

(2) For Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes: Revise the Emergency and Abnormal Procedures sections of the AFM to advise the flightcrew of additional procedures to follow in the event of stabilizer trim runaway and in the event of MACH TRIM, STAB TRIM, and horizontal stabilizer trim malfunctions.

Table 1.—TRs

For Bombardier Model—	Use—	Dated—	To the—
CL-600-2B16 (CL-604) airplanes	Canadair Challenger TR 604/21	August 1, 2006	Canadair Challenger CL-604 AFM, PSP 604-1.
CL-600-2B19 (Regional Jet Series 100 & 440) airplanes	Canadair Regional Jet TR RJ/152-4	August 9, 2006	Canadair Regional Jet AFM, CSP A-012.

(g) When the applicable TR has been included in the general revisions of the applicable AFM, those general revisions may be inserted into the AFM and the applicable TR may be removed, provided the relevant information in the general revisions is identical to that in the TR.

Alternative Methods of Compliance (AMOCs)

(h)(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

(i) Canadian airworthiness directives CF-2006-20, dated August 22, 2006, and CF-2006-21, dated August 23, 2006, also address the subject of this AD.

Material Incorporated by Reference

(j) You must use the applicable service information specified in Table 2 of this AD 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 these documents 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.

Table 2.—Temporary Revisions Incorporated by Reference

Temporary revision	Dated—	To the—
Canadair Challenger Temporary Revision 604/21	August 1, 2006	Canadair Challenger CL-604 Airplane Flight Manual, PSP 604-1.
Canadair Regional Jet Temporary Revision RJ/152-4	August 9, 2006	Canadair Regional Jet Airplane Flight Manual, CSP A-012.

Issued in Renton, Washington, on August 29, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.