Airworthiness Directives; Bombardier, Inc. Airplanes

We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD was prompted by an in-service report of an uncommanded and unannunciated nose wheel steering during airplane pushback from the gate. This AD requires installing new cable assemblies with a pull-down resistor. We are issuing this AD to prevent an uncommanded nose wheel steering during takeoff or landing in the event of an open circuit in the steering system, and possible consequent runway excursion.