Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to 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) series airplanes. This proposal would require revising the Airplane Flight Manual (AFM) to provide the flightcrew with procedures and limitations for operating the airplane with out-of-tolerance angle of attack (AOA) transducers. This proposal also would require, among other actions, measuring the vane angles and voltage of the AOA transducers; reworking the AOA transducer assemblies; repetitive measurements of the resistance of both AOA transducers; and follow-on and corrective actions, as applicable. This action is necessary to prevent flat spots on the potentiometers of the AOA transducers due to wear, which may cause a delay in the commands for stall warning, stick shaker, and stick pusher operation. This action is intended to address the identified unsafe condition.