What is the term for the upward force that counteracts an aircraft's weight?

The upward force that counteracts an aircraft's weight is known as lift. Lift is generated as air flows over and under the wings of an aircraft, creating a pressure difference that forces the aircraft upwards. This phenomenon is primarily explained by Bernoulli's principle and Newton's third law of motion.

When an aircraft moves forward, air travels faster over the top surface of the wings than it does underneath, resulting in lower pressure above the wings and higher pressure below. This pressure difference creates lift, enabling the aircraft to ascend into the air. Understanding lift is crucial in the study of aerodynamics and aviation, as it is one of the four fundamental forces acting on an aircraft during flight. The other forces—thrust, drag, and weight—interact with lift but do not serve the same purpose as lift, which specifically counteracts weight to allow for flight.