Expedition Navigation Software / Apparent Wind Direction

**Posted by nav** 3/26/2022 8:14 am

Hello,
is it possible to add a variable to Expedition showing the apparent wind direction?

On a downwind course I'd like to be able to check with a handbearing compass if we are already affected by the wind shadow of another boat parallel to windward.

**Posted by Ernie M** 3/26/2022 9:35 am

Wouldn't that shift be reflected in the TWD measured on your boat?
Ernie

**Posted by nav** 3/27/2022 7:31 am

No, as the wind shadow follows the apparent direction, not the true one.

When thinking a bit more about it it would also be good to have a variable “apparent wind direction on opposite tack” to judge if in or out the dirty air of a boat to leeward and behind when expecting both to gybe simultaneously.

**Posted by Nick** 3/27/2022 10:59 am

I have looked at that in the past and had it in the 2002 AC, but am not sure I have a handle on the mathematics