Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all deHavilland Inc. Models DHC-2 Mk. I and DHC-2 Mk. II airplanes and for all Bombardier Inc. Model (Otter) DHC-3 airplanes powered by radial engines. This proposed AD would require you to visually inspect the firewall ignition plugs and receptacles for proper lockwire security and replace or modify as appropriate. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Canada. We are issuing this proposed AD to prevent loss of ignition systems during flight caused by improper lockwire security, which could result in engine failure. This failure could lead to a forced landing of the airplane.