If aileron lockout appears as a caution message on the EICAS, you should expect:

• A. Degraded roll controllability at low speeds
• B. Increased roll rate at high speeds
• C. No change in control
• D. Enhanced roll control at all speeds

Answer: (A)

Aileron lockout means one or more ailerons are prevented from moving to protect the wing from excessive loads or flutter. With part of the aileron system disabled, the airplane loses some roll authority. This loss is most noticeable at lower airspeeds, where aerodynamic forces are weaker and any reduction in control surface effectiveness has a bigger impact on roll capability. So you’d expect degraded roll controllability at low speeds. The remaining surfaces may still provide some roll at higher speeds, but overall authority is reduced.