Operation thumb|A Soviet Tu-142MK (with MAD located in aft-facing fin-top fairing) escorted by US Navy Lockheed P-3C (MAD located in projection at base of tail), March 1986 The magnetic anomaly from a submarine is usually very small. One source estimates that it is only about 0.2 nT at a distance of 600 m. Another source estimates that a 100m long and 10 m wide submarine would produce a magnetic flux of 13.33 nT at 500m, 1.65 nT at 1km and 0.01 nT at 5km. To reduce interference from electrical equipment or metal in the fuselage of the aircraft, the MAD sensor is placed at the end of a boom or on a towed aerodynamic device. Even so, the submarine must be very near the aircraft's position and close to the sea surface for detection of the anomaly, because magnetic fields decrease as the inverse cube of distance, one source gives a detection slant range of 500m. The size of the submarine, its hull composition and orientation, as well as the water depth and complexity of the natural magnetic field, determine the detection range. MAD devices are usually mounted on aircraft. For example, one study showed that a horizontal detection range of 450–800m, when aircraft was 200m above a submarine, decreased to less than 150m when the aircraft was 400m above the submarine.
operation thumb|a soviet tu-142mk (with mad located in aft-facing fin-top fairing) escorted by us navy lockheed p-3c (mad located in projection at base of tail) march 1986 the magnetic anomaly from a submarine is usually very small one source estimates that it is only about 02 nt at a distance of 600 m another source estimates that a 100m long and 10 m wide submarine would produce a magnetic flux of 1333 nt at 500m 165 nt at 1km and 001 nt at 5km to reduce interference from electrical equipment or metal in the fuselage of the aircraft the mad sensor is placed at the end of a boom or on a towed aerodynamic device even so the submarine must be very near the aircraft's position and close to the sea surface for detection of the anomaly because magnetic fields decrease as the inverse cube of distance one source gives a detection slant range of 500m the size of the submarine its hull composition and orientation as well as the water depth and complexity of the natural magnetic field determine the detection range mad devices are usually mounted on aircraft for example one study showed that a horizontal detection range of 450–800m when aircraft was 200m above a submarine decreased to less than 150m when the aircraft was 400m above the submarine