Airworthiness Directives; Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500- 1A11 airplanes. This AD was prompted by an investigation that showed a change in the feed-through connector O-ring material at a certain frame increased the electrical bonding resistance due to the current torque specification being inadequate. This AD requires electrical bonding tests between the feed-through connectors and the forward side of the bulkhead at a certain frame, and the installation of two electrical bonding plates, as applicable. The FAA is issuing this AD to address the unsafe condition on these products.