Doppler Speed Log
Doppler Speed Log measures a vessel’s speed through the water or over the seabed.
A Doppler Speed Log can be installed on any type of ship. Large ships can have both bow and stern units, yielding more precise readings of vessel movement, especially useful when docking or anchoring.
As its name indicates, this instrument uses the Doppler’s effect to calculate a ship’s speed. Dual-axis models give bith lateral and fore-and-aft readings. Three-axis systems are used aboard submarines to give vertical speed, as well. The log consists of one or more transducers mounted on the hull and lnked to a display screen on the bridge.
and Others ... : Furuno DS80, BEN ANTHEA