Terminology -VMG & VMC - disambiguation

[rgleason]

Isler started way after ockam. But expedition is excellent.

[rgleason]

Thanks skipperearly for registering your preferences, and the suggestion. I hope there are other skippers (power and sail) that will register their votes. That is the purpose of this post.

[RogerD]

I believe that most "boaters", sail or power, would understand VMG to refer to Velocity Made Good to the next waypoint if a Route is "active", since that is where the route is trying to take you. Whether you are steering by autopilot with OCPN driving it, windvane steering, or a person on the tiller tacking to windward, if a waypoint is being used, that is where you are trying to go.

If there is no active waypoint, the VMG is obvioulsy not referencing a geographic location. In ths case VMG as used above has no meaning.

Speed towards the true wind, on any sailboat heavier that an O'Pen BIC, is meaningless since a change in direction gives an instantaneous change in this value without any change in boat speed, especially on somethig like my Alberg 37. It's only value is in long term plotting of your polar diagram.

I suggest that you come up with some term for this value that is totally different, that cannot be confused with VMG as used above. (Such as RST "Real Speed to True Wind" )

Roger

[rgleason]

After having thought about this some more, and with everyone's thoughtful suggestions, I think we need to use familiar terms but make each of them explicit with a 4 letter acronym (Thank you Barnakiel, your suggestions).

• VMGC (or VMGT) Velocity made good to course (or target)
• VMGW Velocity made good to wind

Thank you all for your input.

[Rasbats]

Trying to display the NMEA sentence VTG, ground speed. Have I missed a setting in Dashboard?

Mike

[SailorMAK]

Well now, this will give me something to ruminate on. And, for the first time in my 5 decades of sailing, I am considering the abandonment of woolies and purchasing a masthead fly. Thank you!