Dutchman's Log

Utility to measure your boat speed over the water. Can also be used to calibrate or to check accuracy of your speed/log device.

A boat's speed may be estimated by timing how long the boat takes to pass a floating object.
The boat length and desired units must be entered in 'Settings'
Two persons are needed, one stands on the bow and the other aft.
The person on the bow throws an object that will float (crumpled piece of paper) into the water, ahead and to one side of the bow.
As it passes the bow at right angles, they shout 'Now', and the person on the stern taps the 'start timing' button.
When the object passes the stern at right angles, the 'stop timing' button is tapped.
The App now calculates and displays the boat speed.

Units in Knots, metres/second or Kilometres/hour Show More