Airworthiness Directives; Bombardier, Inc. Airplanes

We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-102, -103, and -106 airplanes; and Model DHC-8-200 and -300 series airplanes. This AD was prompted by a report of heat damage found on a nacelle firewall after an unsuccessful engine ground start and several events of heat damage found on direct current starter/generator terminal block assemblies. This AD requires an inspection to detect damage on the nacelle firewalls and the terminal block assemblies and to make sure the insulating sleeves are installed and have no damage, and corrective action if necessary. We are issuing this AD to address the unsafe condition on these products.