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.
Sources and Resources
http://www.fas.org/man/dod-101/sys/ship/weaps/mk-4-log.htm
Maintained by Robert Sherman
Originally created by John Pike
Updated Wednesday, June 30, 1999 4:31:35 AM