Where sin and cos are the trigonometric sine and cosine functions. The resulting force equations are shown on the slide: Vertical: L – W + T sin(c) = Fv Horizontal: T cos(c) – D = Fh With new mechanical systems it is possible to deflect the engine exhaust from the nozzle and cant the thrust vector at an angle. Since the thrust force is already a large force for fighter aircraft, designers have sought ways to bring this force into the vertical equations of motion. The ability to climb and maneuver involves the vertical net force as well as the excess thrust. Good fighter aircraft have high excess thrust. The quantity (T – D) is called the excess thrust and is related to the aircraft’s ability to accelerate. If we denote the thrust by the symbol T, the lift by L, the drag by D, and the weight by W, the usual force equations for an aircraft in level flight are: Vertical: L – W = Fv Horizontal: T – D = Fh Excess Thrust
One equation gives the the net vertical force Fv, and the other gives the net horizontal force Fh. There are two component equations for the force on an aircraft. The resulting acceleration, velocity and displacement of the aircraft are also vector quantities which can be determined by Newton’s second law of motion and the rules of vector algebra.
Vector Quantitiesįorces are vector quantities having a magnitude and a direction. The ability to change the angle of the thrust is called thrust vectoring, or vectored thrust. Some modern fighter aircraft can change the angle of the thrust by using a movable nozzle. For an aircraft in cruise, the four forces are balanced, and the aircraft moves at a constant velocity and altitude. The motion of the aircraft through the air depends on the relative size of the various forces and the orientation of the aircraft. There are four forces that act on an aircraft in flight: lift, weight, thrust, and drag. Home > Beginners Guide to Aeronautics Vectored Thrust
0 kommentar(er)
