Summary
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 787-8 airplanes. This proposed AD was prompted by reports of a potential latent failure of the valve actuator circuitry, which was not identified during actuator development. This proposed AD would require replacing certain engine and auxiliary power unit (APU) fuel shutoff valve actuators with new actuators, and would also require revising the maintenance or inspection program to include a new airworthiness limitation into the Airworthiness Limitations Section (ALS) of the Instructions for Continued Airworthiness (ICA). We are proposing this AD to prevent latent failures of the fuel shutoff valve actuators, which could result in the inability to shut off fuel to the engine or APU in the case of an engine or APU fire. If the fuel cannot be shut off to a fire, the engine or APU fire could be uncontrollable, which could lead to structural failure.