How does a plane actually fly?
A fully loaded jumbo jet the Boeing 747-400 weighs more than 385 tonnes. Lifting this mass off the ground to allow the plane to fly depends on a physical phenomenon known as aerodynamic lift. This stems from a pressure difference when the plane accelerates. The air flows over the cambered top surface of the wing faster than over the flat underside, resulting in underpressure (negative) over the top of the wing and overpressure (positive) beneath it. The two work together to generate the upward force called aerodynamic lift.Once the lift is greater than the plane’s weight, it can take off from the ground and fly. However, the airflow-and wheels-grip onto the ground as the plane rolls down the runway prior to take off causing resistance or drag. This has to be overcome by thrust from the engines. If the thrust is greater than the resistance, the plane accelerates. In cruise flight, the forces are in equilibrium with lift equalling weight and thrust equalling resistance; cruising height a
