Low-noise level landing apparatus and system for helicopters

Abstract

A low-noise level landing apparatus for helicopters comprises a helicopter position calculator for calculating the position of the helicopter, a data input device, an air data sensor for measuring an airspeed and a descending angle, a rotor tachometer for detecting a rotor rotational speed, a memory and a fuel gauge for calculating the weight of the helicopter, a rotor rotational speed controller for controlling the rotor rotational speed, a BVI noise generating area database device for storing noise levels in accordance with parameters of descending speed, airspeed, descending angle, rotor rotational speed and weight of the helicopter. A computer selects a flight route, an airspeed, a descending angle and a rotor rotational speed wherein noise is reduced, by setting a plurality of flight routes on the basis of the helicopter position and landing point and by referring to the noise generating area database device. Low-noise level landing is then carried out by pilot manual control or automatic flight control. By modifying the selected flight route on the basis of ground noise data received by a data receiver, the optimal flight route is reselected. As a result, a flight route wherein noise reduction can be attained during landing can be selected more properly.