Miss Distance Indicator AS-131
The MDI is a universal type, i.e. it handles all target courses relative to the firing gun or missile, i.e. all types of attacking and passing courses.
The MDI consists of a microphone nose containing six pressure sensors, and a cylindrical body containing the electronics, the transmitter, and a rechargeable NIMH accumulator.
The miss distance indicator AS-131 detects acoustically the shock wave generated by the passing supersonic projectile.
The miss distance is determined by the amplitude of the shock wave while the angular position is determined from the hit order between the different pressure sensors in the MDI nose.
The miss distance and the angular position of the projectiles are measured in real time and the data is transmitted as raw data signals via the special designed transmitter to the scoring station. Since raw data is used, all calculations are made in the scoring station.
A recalculation of the scoring result, with later more accurate parameters, can easily be made in the scoring station for further improved accuracy.
