Critical Uncertainties

This post is part of the Airbus aircraft family and system safety thread.

While there’s often a lot of discussion about short term response of aircraft to control inputs, in practice it’s often the long term response of the aircraft state vector at constant thrust and neutral control inputs that’s just as important to flight control system designers. In the case of Airbus the selection by the designers of a modified C* feedback loop (1) for primary pitch axis control law (Airbus 1998) in flight has led to what you’d call interesting consequences. Continue Reading…