Airworthiness Directives; Bombardier, Inc. Airplanes

We propose to adopt a new airworthiness directive (AD) for all Bombardier, Inc. Model CL-600-2D15 (Regional Jet Series 705) and CL- 600-2D24 (Regional Jet Series 900) airplanes. This proposed AD was prompted by two in-service incidents reported on Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 701, & 702) airplanes regarding a loss of all air data information in the flight deck. This proposed AD would require revision of the airplane flight manual (AFM) to provide procedures to guide the crew to stabilize the airplane's airspeed and attitude for continued safe flight. We are proposing this AD to prevent loss of air data information that may affect continued safe flight.