Acoustic navigation system to provide helicopter
landing in blind-flying conditions


Development of an acoustic system for measuring the current coordinates of a helicopter in the course of its maneuvering and landing. The system provides a safe helicopter landing in adverse weather conditions with poor optical visibility.

System components and principle of operation

The system consists of ground and on-board equipment. The ground equipment includes:

  • a receiving base consisting of spatially separated microphones;
  • signal processing equipment, which provides the estimates of the current coordinates and displays the trajectory of the helicopter relative to the selected point of landing;
  • a radio transmitter for sending the coordinate data (and official information) to the helicopter board.

The principle of operation is as follows. The noise radiation produced by the helicopter is received by the microphone base, the received signals are supplied to the hardware unit where the current coordinates of the helicopter (the angle of elevation, the azimuth, the height, and the slant range) are estimated. The coordinate data are transmitted through an ultrashort-wave radio channel to the helicopter board and displayed on its regular display.

Degree of readiness

A prototype of the acoustic system of helicopter landing is developed and manufactured (without the radio channel). The system was tested in full-scale conditions on the airfield of the Gromov Flight Testing Center. The test results demonstrated the high efficiency and reliability of the system.

The range of the helicopter detection and tracking is 1300-1500 m (in the coordinate-measurement mode of operation). The rms error in the coordinate measurements within a range of 100 m is about 0.5 m.

The system structure provides the possibility of its fast installation on arbitrary landing areas.

The Acoustics Institute is ready to fulfil the orders for the design and manufacture of the acoustic navigation system for helicopter landing.

Height trajectory of the helicopter flight
Height trajectory of the helicopter flight
Trajectory of the helicopter flying over the point of landing
Trajectory of the helicopter flying over the point of landing