Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Bombardier Model CL-600- 1A11 (CL-600) and CL-600-2A12 (CL-601) series airplanes. This proposal would require modification of the main landing gear (MLG) brake units and inboard MLG wheels; and a revision to the Airplane Flight Manual (AFM) to include the increased cooling times for the modified brakes. This proposal also would allow, for certain cases, removal of the inboard and/or outboard wheel discs by installation of a placard to limit airplane operation on the ground and a revision to the AFM to include information for operating the airplane with the wheel discs removed. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent water freezing on the brake while the airplane is in flight due to water, slush, or snow from the runway entering into the brake assemblies during takeoff, and consequently, a tire burst during landing of the airplane.