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 reports that operation of fuselage doors was interrupted due to corrosion in certain door roller bearings. This AD requires a one-time detailed inspection of the bearings for corrosion, and replacement if necessary. We are issuing this AD to address the unsafe condition on these products.