Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model DHC-8-400 series airplanes. This AD was prompted by the failure of the fire control amplifier (FCA), which was likely caused by an electrical short in a discharged squib for a fire extinguishing bottle. This AD requires replacing certain circuit breakers. We are issuing this AD to address the unsafe condition on these products.