Female Speaker: Aircraft the heavier than air. So it must be a combination of forces that allows them to fly. The forces that affect an aircraft in flights are its weight the lift produced by air flow over the wings the thrust produced by the engines and the drag or air resistance. Most modern high speed air craft are powered by jet engines which produce the thrust force. This thrust is greater than the drag and drives the aircraft forwards. In the turbo fan engine air is subtend by spinning fans compressed and forced at high pressure into the combustion chamber. Here the burning fuel heats the air which expands and rushes out at great force spinning the turbine fan which in turn drives the suction fans at the front the jet of gases streaming backwards produces forward acting thrust to produce the lift the aircraft has specially shaped wings cool the air foils, air passing over the top wing surface travels further and faster then the air passing underneath this results in high pressure below the wing and low pressure above creating the light force which counteracts the weight of the aircraft.