Runway and obstacle detector to improve airplane landing

Abstract

An airplane flies through the air because the forward speed of its wings through the air produces lift which is greater than the total weight of the craft. When the forward speed decreases below a certain amount, there is insufficient lift to counteract the weight of the plane and the plane will drop down (or stall). This is the ideal condition of speed at which an airplane lands, but it is important that the stall occur when the plane is only a very short distance (like three feet) above the ground. It is also very important that the plane remain well above the ground or other obstacles until a suitable landing field is reached. The device herein described uses "sonar" or reflections of sound pulses to give the pilot an audible indication of his exact distance from the ground so that he can know the correct moment to stall or "flare" the plane for a perfect landing. The device also warns of obstacles when they are less than 100 feet below the aircraft to warn the pilot if he is flying too low before reaching the airport.

Dependencies are inferred from the claim text.