Abstract: A method is provided for determining at least one of the coefficient of lift and the coefficient of drag of a golf ball for a given range of velocities and a given range of spin rates from launch. A method is also described for simulating the flight of a golf ball in a computer. A ball is launched at a selected velocity, spin rate and launch angle. Calculations are made of the x and y coordinates of the ball during flight and the coefficients of lift and/or drag are calculated mathematically in dependence on the launch velocity, spin rate, angle and calculated x and y coordinates. Repeated launchings are made to obtain a plurality of mathematically calculated values of the coefficient(s). Thereafter, an aerodynamic model for the flight of the ball is mathematically determined in dependence upon the mathematically calculated values of at least one of the coefficients relative to the velocity and spin rate.

Abstract: The test range is provided with a calibration system for calibrating the exact position of a light curtain formed by a ballistic screen. The calibration system uses a model ball which can be moved through a light screen at high speed in order to simulate the actual passage of a driven golf ball through the light screen. Positioning of the model golf ball at a point at which the golf ball just contacts the light screen serves to determine the exact location of the light screen. A laser ranging device is used to locate the calibration system relative to a launch point. Thus, the precise distance of the curtain of light from the launch point can be readily determined. The calibration system may also be used to determine if a ballistic screen is mounted in a true vertical plane.

Abstract: The system for determining the carry and/or lateral deviation and/or flight time of a driven golf ball uses a grid of geophones to sense the time of impact of a driven golf ball. The geophones are buried in the ground so that the impact is sensed via sound waves travelling through the ground. A computer receives a signal from each sensor indicating an impact and determines the time at which the impact was sensed by each sensor and screens out all but the six shortest times of impact. This information is then used to mathematically calculate the point of impact within a square of geophones corresponding to the recorded times. A plot of the flight path of the golf ball can be displayed on a display monitor based upon the carry and the flight time. The calculated flight time and carry are compared with a known standard to determine conformance with the standard.