Airworthiness Directives; Bombardier, Inc. Airplanes

We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model BD-100-1A10 (Challenger 300) airplanes. This AD was prompted by multiple reports of erratic electrical status indications on the push button annunciators and the engine instrument and crew alerting system. Certain of those reported incidents resulted in the airplane experiencing a momentary loss of electrical power and loss of flight displays. This AD requires modification of the direct current power centers. We are issuing this AD to prevent loss of electrical power, which could result in the loss of flight displays and reduced controllability of the airplane.