The AOA amber donut will continue to indicate the optimum no-wind airspeed in the landing pattern as aircraft weight decreases.

• A. Optimum no-wind airspeed in the landing pattern
• B. Stall speed
• C. Maximum endurance speed
• D. No-wind best range glide speed

Answer: (A)

The amber donut marks the target angle of attack that gives the most efficient flight in no-wind conditions, which in the landing pattern translates to the optimum no-wind airspeed for a stable, energy-efficient approach. That particular angle of attack (the one behind the amber donut) is essentially constant for a given configuration because it corresponds to the aircraft’s best lift-to-drag ratio. Therefore, as weight changes, the indicator still points to the same optimum no-wind landing speed because it’s tied to that fixed aerodynamic condition, not to a fixed weight value. In other words, the instrument is guiding you to the most efficient no-wind landing speed for the current configuration, which doesn’t depend on weight.