Safety experts say they’re seeing cases in which pilots who are suddenly confronted with a loss of computerized flight controls don’t appear to know how to respond immediately, or they make errors — sometimes fatally so.

A draft FAA study found pilots sometimes “abdicate too much responsibility to automated systems.”

Because these systems are so integrated in today’s planes, one malfunctioning piece of equipment or a single bad computer instruction can suddenly cascade into a series of other failures, unnerving pilots who have been trained to rely on the equipment.