Action
Final rule; request for comments.
Summary
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 787-8 and 787-9 airplanes. This AD requires revising the airplane flight manual (AFM) to instruct the flightcrew to avoid abrupt flight control inputs in response to sudden drops in airspeed, and to reinforce the need to disconnect the autopilot before making any manual flight control inputs. This AD was prompted by reports indicating that in certain weather conditions with high moisture content or possible icing, erroneous low airspeed may be displayed to the flightcrew before detection and annunciation via engine-indicating and crew-alerting system (EICAS) messages. We are issuing this AD to ensure that the flightcrew avoids abrupt pilot control inputs in response to an unrealistic, sudden drop in displayed airspeed at high actual airspeed. Abrupt pilot control inputs in this condition could exceed the structural capability of the airplane.