HELICOPTER CARRIED MAGNETOMETER ASSEMBLY COMPENSATED FOR THE PARASITIC FIELD OF THE HELICOPTER

摘要

A magnetometer assembly for detection of ferromagnetic targets carried by a helicopter is compensated for the parasitic magnetic field generated by the helicopter. First and second magnetometer heads are carried by the helicopter and located at points aligned with the axis of the main rotor. An electric control signal representative of the difference of the total magnetic fields at the first and second heads is obtained and is used to compensate the parasitic component due to the helicopter in the magnetic field at one of the points. The distance between the heads and the rotor is large as compared to the variations of the position of the magnetic center of gravity of the helicopter and as compared to the distance between the heads.