Heavy gross weight has what effect on stall speed?

Heavy gross weight has what effect on stall speed?

• A. Increases stall speed
• B. Decreases stall speed
• C. No change
• D. Doubles stall speed

Answer: (A)

Stall speed is the speed at which the wing can produce enough lift to balance the aircraft’s weight. With CLmax fixed for a given configuration, the lift at stall equals weight: W = 0.5 ρ V^2 S CLmax. Solving for stall speed gives V_stall = sqrt((2W) / (ρ S CLmax)). So as gross weight W increases, stall speed increases with the square root of W. This means heavier weight requires a higher airspeed to avoid stalling. It’s not a simple linear rise, nor a decrease or no change; doubling weight increases stall speed by about 41%, not doubling.

Stall speed is the speed at which the wing can produce enough lift to balance the aircraft’s weight. With CLmax fixed for a given configuration, the lift at stall equals weight: W = 0.5 ρ V^2 S CLmax. Solving for stall speed gives V_stall = sqrt((2W) / (ρ S CLmax)). So as gross weight W increases, stall speed increases with the square root of W. This means heavier weight requires a higher airspeed to avoid stalling. It’s not a simple linear rise, nor a decrease or no change; doubling weight increases stall speed by about 41%, not doubling.