Latest News: Forums Cruising Boat Speed with outboard Re: Re: Boat Speed

#7703
Swiebertje
Participant

@Simon McE wrote:

Dave Mac wrote:
As a slight deviation how have people here established their boat speed? Mine was a guestimate and obviously over a distance you could calculate your speed from time travelled and maps or charts. Or were most people reading off handheld GPS?
I use a GPS to get SOG

I had a SOG of 5+ knots once while motoring, then I realized I had a 3 knot current running with me…..

When talking about boat speed and engine power we should only consider speed through the water. An Engine does not help with or against current.

I always tell other sailors that anything over 2 hp is for others (as in towing others). If you want to go in a plane with a boat like a Wayfarer you would probably need a 10 to 15 hp engine. The weight of these buggers is something you don’t want on your transom. Having said that, it is safe to assume we are, like many other sail boats, limited by our hull speed. A 2 hp Engine easily pushes a Wayfarer up to its hull speed and once there you can go back to almost half throttle. If you want to tow three or more other wayfarers a 4 hp may be a better choice but remember that a 2 hp weighs 11 to 12 kg and a 4 hp 20 to 24 kg. That weight is where you least want it, at the transom. That makes the choice easy I would say.