Why does maneuvering speed decrease at lighter weight?

• A. Engine power changes with weight
• B. Effects of aerodynamic forces become more pronounced
• C. Wing loading increases
• D. Stall speed increases with light weight

Answer: (B)

The key idea is how weight affects the load the airplane can safely carry from aerodynamic forces. Maneuvering speed is the speed at which a sudden, full control input would push the airplane to its limit load factor without overstressing the structure. When the airplane is lighter, it has less inertia and less weight to support the same aerodynamic lift. A gust or a rapid control input then produces a larger load factor (lift relative to weight) than it would at a heavier weight. So the airframe reaches its limit load at a lower speed, meaning maneuvering speed decreases as weight decreases. This is why lighter airplanes are more sensitive to aerodynamic forces, and Va drops accordingly.