How should the aircraft be handled during the controllability check regarding airspeed?

During a controllability check, the correct approach is to fly no slower than the minimum controllable airspeed plus 20 knots indicated airspeed (KIAS). This practice ensures that the aircraft remains within a safe envelope where it can be adequately controlled.

By flying slightly above the minimum controllable airspeed, pilots can avoid the risk of entering a stall or experiencing a loss of control. Minimum controllable airspeed represents the lowest speed at which the aircraft can be controlled without stalling; thus, adding an additional buffer enhances safety and provides a margin for any sudden changes in aircraft dynamics or pilot inputs.

Choosing to fly at maximum speed, minimum controllable airspeed, or cruise speed does not adequately address the balance between safety and control needed during a controllability check. Maximum speed might push the aircraft beyond the limits required for this check, while minimum controllable airspeed could lead to stability issues. Cruise speed does not pertain to the specific requirements for evaluating controllability at lower speeds, which is the focus of the task at hand.