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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0408; Directorate Identifier 2008-NM-068-AD;
Amendment 39-15458; AD 2008-08-06]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model CL-600-1A11 (CL-600),
CL-600-2A12 (CL-601), CL-600-2B16 (CL-601-3A, CL-601-3R, & CL-604
(Including CL-605 Marketing Variant)) 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.

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SUMMARY: The FAA is superseding an existing airworthiness directive
(AD) that applies to all Bombardier Model CL-600-2B19 (Regional Jet
Series 100 & 440) airplanes and Model CL-600-1A11 (CL-600), CL-600-2A12
(CL-601), and CL-600-2B16 (CL-601-3A, CL-601-3R, and CL-604) series
airplanes. The existing AD currently requires revising the airplane
flight manuals (AFMs) to include a new cold weather operations
limitation. This AD requires revising the AFMs to modify the cold
weather operations limitation and include additional limitations and
procedures. This AD results from reports of uncommanded roll during
take-off. We are issuing this AD to prevent possible loss of control on
take-off resulting from even small amounts of frost, ice, snow, or
slush on the wing leading edges or forward upper wing surfaces.

DATES: This AD becomes effective April 21, 2008.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the AD as of April 21,
2008.
On February 22, 2005 (70 FR 8025, February 17, 2005), the Director
of the Federal Register approved the incorporation by reference of
certain other publications.
We must receive any comments on this AD by May 14, 2008.

ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
For service information identified in this AD, contact Bombardier,
Inc., Canadair, Aerospace Group, P.O. Box 6087, Station Centre-ville,
Montreal, Quebec H3C 3G9, Canada.

Examining the AD Docket

You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The street address for
the Docket Office (telephone 800-647-5527) is in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.

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 (516) 228-7328; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

On February 10, 2005, the FAA issued AD 2005-04-07, amendment 39-
13979 (70 FR 8025, February 17, 2005). That AD applies to all
Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes
and Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16
(CL-601-3A, CL-601-3R, and CL-604) series airplanes. That AD requires
revising the airplane flight manuals to include a new cold weather
operations limitation. That AD resulted from a report that even small
amounts of frost, ice, snow, or slush on the wing leading edges or
forward upper wing surfaces can cause an adverse change in the stall
speeds, stall characteristics, and the protection provided by the stall
protection system. The actions specified in that AD are intended to
prevent possible loss of control on take-off resulting from even small
amounts of frost, ice, snow, or slush on the wing leading edges or
forward upper wing surfaces.

Actions Since AD Was Issued

Since we issued that AD, Transport Canada Civil Aviation (TCCA)
informed us that there were three incidents in which Model CL-600-2B19
and CL-600-2B16 airplanes experienced uncommanded roll during take-off.
TCCA advises that it is necessary to further revise the AFM limitations
and procedures for cold weather or icing conditions.

Relevant Service Information

Bombardier has issued the temporary revisions (TRs) listed in the
following table. The temporary revisions describe limitations that
include tactile inspections for ice during certain weather conditions.
The temporary revisions also describe limitations and procedures for
use of wing and cowl anti-ice during certain taxiing or take-off
conditions, and revised take-off limitations to reduce high-pitch
attitudes during rotation. TCCA mandated the service information and
issued Canadian emergency airworthiness directives CF-2008-15, dated
March 7, 2008, and CF-2008-16, dated March 10, 2008, to ensure the
continued airworthiness of these airplanes in Canada.