In flight dynamics, what does load factor measure?

In flight dynamics, what does load factor measure?

• A. The engine thrust per unit weight.
• B. The amount of lift stored in the wing structure.
• C. The ratio of total load experienced by the aircraft to its weight.
• D. The rate of change in altitude.

Answer: (C)

The question is about how much load the aircraft experiences compared to its own weight. Load factor is the ratio of the total load the airframe feels to its weight, essentially telling you how many g’s the aircraft is experiencing. In steady, level flight, lift balances weight, so the load factor is 1. During maneuvers that require more lift to provide the necessary turning or accelerating forces, the wing must carry more than weight, so the load factor becomes greater than 1. For a level turn with bank angle, the lift must support weight vertically, giving L = W / cos(phi), so the load factor n = L/W = 1/cos(phi). For example, a 60-degree bank yields about 2 g. This isn’t about thrust per unit weight (that’s thrust-to-weight), nor about how much lift is stored in the wing, nor about how quickly altitude changes.

The question is about how much load the aircraft experiences compared to its own weight. Load factor is the ratio of the total load the airframe feels to its weight, essentially telling you how many g’s the aircraft is experiencing. In steady, level flight, lift balances weight, so the load factor is 1. During maneuvers that require more lift to provide the necessary turning or accelerating forces, the wing must carry more than weight, so the load factor becomes greater than 1. For a level turn with bank angle, the lift must support weight vertically, giving L = W / cos(phi), so the load factor n = L/W = 1/cos(phi). For example, a 60-degree bank yields about 2 g.

This isn’t about thrust per unit weight (that’s thrust-to-weight), nor about how much lift is stored in the wing, nor about how quickly altitude changes.