Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 787-8 and 787-9 airplanes. This proposed AD was prompted by a determination that certain areas in the tire/wheel threat zones could be susceptible to damage, which could result in loss of braking on one main landing gear (MLG) truck, loss of nose wheel steering, and loss of directional control on the ground when below rudder effectiveness speed. This proposed AD would require installing hydraulic tubing, a pressure-operated check valve, and new flight control software. We are proposing this AD to address the unsafe condition on these products.