Towing a boat, what speed to use for passage planning?

[Rappey]

, I’m wondering what sort of speeds to expect whilst towing?

I would think around 4knts comfortably in calm conditions.

 

[tillergirl]

I towed a 43ft yacht 9000kg displacement for about 4.8nm. Conditions were pleasant - about nothing more than 10kts of wind from aft. The engine had plenty of bottom torque so we used about 1800 revs and achieved about 4 kts. Occasionally the wind did pick up slightly and the tow did get a wave that very slightly caught us up for a few seconds and then the tow re-tensioned. This only happened a few times or we would have had to reassess speed/course.