Load factor is a frequently misunderstood term in the aviation industry. All airplanes have surfaces that produce lift. Known as lifting surfaces, they feature an aerodynamic design that allows air to flow under and over them.
The pressure difference between the top and bottom airflow of these lifting surfaces creates lift. Wings, for instance, have air flowing over the top of them and underneath them. The air moves faster over the top of an airplane’s wings, resulting in less pressure compared to the air flowing under the wings. This pressure difference results in lift. But the weight of an airplane will act against the airplane’s lift, which is why it’s important for pilots to consider load factor.
Overview of Load Factor
The term “load factor” is typically used to describe the ratio of an airplane’s lift to its weight. Airplanes rely on lift to take off and stay in the air. Whether it’s a turboprop, turbofan or any other type of airplane, it will produce lift using aerodynamic surfaces. Load factor reveals how much lift an airplane produces relative to the airplane’s total weight.
Load Factor Formula
There’s a simple formula used to calculate an airplane’s load factor. It involves dividing the airplane’s lift by its weight (N=L/W).
N represents the airplane’s load factor. L represents the airplane’s lift. W represents the airplane’s weight. If you know the lift and weight of an airplane, you can calculate its load factor using this formula.
Why Load Factor Is Important
So, why is load factor important exactly? It provides insight into the physical stress to which airplanes are subjected during flight. An airplane’s lifting surfaces may sustain damage if the airplane exceeds a certain load factor limit.
Aviation authorities have limits for load factors. Helicopters, for instance, are typically required to have a load limit of −1 to +3.5, whereas most commuter airplanes must have a load limit of −1.52 to +3.8. Exceeding these load limits can result in damage to the aircraft due to excessive stress.
Load factor will affect an airplane’s stall speed as well. As the airplane’s load factor increases, so will its stall speed. The airplane will be able to fly at a slower airspeed without stalling and losing lift.
In Conclusion
In the aviation industry, load factor is a measurement of how much lift an airplane produces relative to its total weight. It’s important because it reveals the stress to which the airplane’s lifting surfaces are subjected during flight. Load factor will also affect the airplane’s stall speed, as a higher load factor translates into a faster stall speed.
