Which factor is not listed as affecting stall speed in the provided material?

• A. Weight
• B. Load factor
• C. Power
• D. Altitude

Answer: (D)

Stall speed is the speed at which the wing can generate enough lift to balance the aircraft’s weight at the maximum lift coefficient. When the aircraft is heavier, more lift is required, so the speed must be higher to avoid stalling. In a turn, the load factor increases, so the wing must support more weight than in straight-and-level flight, which also raises the stall speed. The engine power setting doesn’t change the wing’s lift capability at a given angle of attack, so it doesn’t set the stall speed in the usual sense. Altitude matters for true stall speed because air density changes with height, but the material uses indicated airspeed, which is designed to stay roughly the same with altitude in standard atmosphere. That’s why altitude isn’t listed as a factor affecting stall speed in the provided material.