Summary
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, Model 757 airplanes, Model 767 airplanes, and Model 777 airplanes. This proposed AD results from fuel system reviews conducted by the manufacturer. This proposed AD would require an inspection to determine if certain spar-mounted motor-operated valve actuators for the spar-mounted fuel valves are installed, and replacement of any affected actuators. We are proposing this AD to prevent electrical energy from lightning, hot shorts, or fault current from entering the fuel tank through the actuator shaft, which could result in fuel tank explosions and consequent loss of the airplane.