SailNet Community - View Single Post - Experience with Garmin GMI 10 and related NMEA 2000 sensors?
View Single Post
Old 03-27-2013
knuterikt knuterikt is online now
Senior Member
Join Date: Aug 2006
Location: Norway
Posts: 766
Thanks: 7
Thanked 57 Times in 52 Posts
Rep Power: 9
knuterikt is on a distinguished road
Re: Experience with Garmin GMI 10 and related NMEA 2000 sensors?

Originally Posted by OS2Dude View Post
GPS (Ground Speed) is MUCH more useful. It is your ACTUAL speed. The water speed is how fast the water is under your hull. If you are at anchor and there is a current, you will display a water speed but not a ground speed. If you sail WITH the current, water speed will be less (possibly even negative) than your ground speed. If you sail against the current, you can show a much greater 'speed' than what you are actually going compared to ground.
Don't know where you sail but having both SOG (Ground Speed) and STW (speed through water) can give me important information on the direction of the current.

When I sail with the current I will try to use it to my advantage.
When the current is against i seek into water with less depth as I know the effect is less there. Short tacking in water with less depth is better if the current is against..
Reply With Quote Share with Facebook