Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 777 airplanes. This proposed AD was prompted by reports of dual pitch rate sensor (PRS) failures, resulting in autopilot disconnects. This proposed AD would require an inspection to determine the PRS part number and replacement if necessary. We are proposing this AD to prevent a dual PRS failure that could cause an automatic disengagement of the autopilot and autoland, which may prevent continued safe flight and landing if disengagement occurs at low altitude and the flight crew is unable to safely assume control and execute a go-around or manual landing.