I4

Using potential functions for a cylinder, one can model a ridge that is used for ridge soaring by a sailplane. When ridge soaring, the sink velocity of the sailplane is compensated by the upward component of the wind as it is deflected by the ridge. In our problem, the ridge height of 800 ft can be modeled using a streamline passing over a cylinderwith a radius of R=600ft. The sailplane has a minimum sink rate of 115 ft/min. At what velocity, U., is the wind velocity perpendicular to the ridge sufficiently strong in order for the sailplane to maintain flight at a constant altitude that equals the height of the ridge? Tin