Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Possible chafing between [the] electrical feeder cable connected to contactor 123P/2 and ground point 803GND, installed within the left DC power box, discovered during routine receiving inspection. This condition may exist on boxes installed on in-service aircraft. If this chafing condition is left unattended, an electrical short may develop, leading to disconnection of the battery and battery bus from the electrical system of the aircraft, [which could result in] overheating, arcing, smoke and fire.
The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.