Airworthiness Directives; Bombardier, Inc. Airplanes

We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This proposed AD was prompted by the discovery of a number of incorrectly calibrated angle of attack (AOA) transducers installed in the stall protection system. This proposed AD would require replacement of incorrectly calibrated AOA transducers. We are proposing this AD to detect and replace incorrectly calibrated AOA transducers; incorrect calibration of the transducers could result in late activation of the stick pusher.