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 of arcing and smoke emanating from the windshields. This AD requires a revision to the maintenance or inspection program, as applicable, to include an inspection of the windshield moisture seal for signs of cracks, erosion, wear, and other deterioration; doing that inspection and repair if necessary; and re-torqueing the screws that fasten the windshield heater terminal lugs and applying sealant to the screw heads of the windshield heaters. We are issuing this AD to address the unsafe condition on these products.