Mk 4 Mod 2 Electromagnetic Underwater Log System
The Electromagnetic (EM) Underwater Log System Mk 4 is an underwater speed measuring system that provides ownship speed and distance-traveled relative to the water. The EM Log System determines speed and distance traveled from an electromagnetic flow-sensing device which produces a voltage proportional to ship's speed through the water that is converted into synchro output signal. The output signal is then distributed to speed indicators and combat system users.
