what does thrust mean in flight
For flight to take place, thrust must be equal to or greater than the drag. If, for any reason, the amount of drag becomes larger than the amount of thrust, the plane will slow down. If the thrust is increased so that it's greater than the drag, the plane will speed up. On the next page, we'll discuss weight and lift.
When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction on that system.[1] The force applied on a surface in a direction perpendicular or normal to the surface is called thrust.