How fast will a 10 hp motor push a 48 foot and 30,000 # sailboat?

[Aaron42]

I bet you get a couple of knots but it will take a while to get there. You won't make any headway against any current, wind or waves. You probably won't even get enough power to maintain headway in a crosswind.

Here's a tip. Time how long it takes you to get from a dead stop until whatever speed you max out at. If you throw the engine in reverse it will take you at least that long to come to a dead stop.

[S/V Alchemy]

Originally Posted by Cheechako

That's a heavy boat for sure. Are we talking a 42-45 ft boat? I'm not sure, but my guess is it will move it. It will take a while to get it going then chug along.... if the OB doesn't overheat.
Let's see.... a 10 HP on a dingy tied alongside a 12000 lb trawler would move it maybe 3.5 knots in flat water. (don't ask how I know!)

That tallies. I had our Atomic 4 die on a 10,000 lb. 33 foot sloop, and our 9.9 HP Honda BF100 on a Zodiac 310 RIB on the hip of the sloop pushed us at 4.2 knots but was quite warm after an hour of that. The oil got changed promptly.

10 HP on a big arsed vessel like that would in my view barely give steerage way and would have to have the right prop to be effective.

[Panope]

There seems to be a large discrepancy between people's experience that I cannot explain.

I moved Panope (15,000 lb) 1.5 miles with a Yamaha 6 hp at 1/3 throttle (just above the "start" position). Probably using about 2 horsepower, maybe 3.

Boat speed was 3+ knots.

Propeller has slightly less pitch than stock (dinghy will still plane, although slower).

Engine temperature stayed normal - cool.

Used less than half of the 1 liter fuel tank.

The pictured motor steering angle resulted in a centered helm of the mother ship.

This set-up functioned so well, that I would not hesitate embarking on a multi day, protected water cruise with a dead main engine.

Steve

https://www.youtube.com/watch?v=f0Gt...ature=youtu.be

Close-up of the throttle position shown just above the "start" position.

[Camille1]

I have a 9.9hp Yamaha outboard which I have used on two occasions to tow my 49ft monohull (a Northwind 50) a number of miles (five on one occasion). I strap my Avon 3.4 inflatable alongside, bow and stern, set the outboard going at three quarters throttle, and get back on board the sailboat to steer.

In reasonably calm conditions I achieve two and a half to three knots which is enough to get me out of trouble without the need to be rescued.

Quite possibly quicker than fixing the main engine or prop and more certain of reaching a safe haven.

If there is any wind you can always use sails, or course!

Hope you find this useful.

[nauticalnomad]

I know it will go faster if you all stand at the back and get it on the plane.

[Cadence]

It sounds like towing insurance would be worth while and a good anchor.

[nautitrix]

Originally Posted by SecondBase

Assume perfect day - no wind, no current, etc. for a one time transport of a number of miles prior to refit.

I have moved a 15000#, 37 foot boat, with four people on board about 3 miles, in a mild chop with a 9.9 Evinrude 2 stroke. I believe I was up to about 3 1/2 knots by the time I had to get the other boat docked.
I will warn you that moving the boat is not anywhere near as difficult as stopping the larger boat. I was fortunate in my landing, as four members of the Canadian Coast Guard were on the dock and ready to take the lines and snub it to a stop.
Be sure to have people ready for the docking and give yourself lots of time to stop the boat in open water and then nudge it to the dock.

[nautitrix]

Do not use reverse to stop the forward momentum unless you have a sail drive outboard with an appropriate propellor. When you are building momentum just keep backing off the throttle until you are on the edge of cavitation.
I am not sure how much the going bet is but I will take it, two to one, on you having no problems pushing or towing. I've done both multiple times, a good bit of awareness will see you through.

[buzzstar]

Originally Posted by Don C L

2.85 knots.

Since we seem to be doing exact rather than over/under or something similar, without knowing any of the variables, distance, route, bottom (of boat) etc., I am going with 2. 366 knots average from cast off to arrival.

[Kudu]

The full motor power will not be available to you if you use a standard prop. If you are going to try it, you really need to get the low pitch "sail" version prop.

Make sure you have your sails and anchor ready to deploy quickly too!

[Pelagic]

The issue is not moving it...the challenge is stopping it with wind and current behind you.

Having said that....I did exactly the same thing in 2015 when I towed my 40 ton Stargazer to a refit slip for painting and the engine room gutted.

Short trip but the NE monsoon could fill in early and I would be towing into a long cut with the wind behind me.

I set up a long towing bridal and tied to my tender bow with a slip knot. Outboard was a standard 15hp that was used in reverse.
Me on the tender, my girlfriend steering SG and a helper for lines

Sure enough the wind started to fill in behind me as I entered the cut. But I had preset a large floating poly line to a mooring anchor and did a 180° turn into the wind... let the boat drift over the poly while I they picked up the mooring line.

Worked perfectly as the wind built up to 25 knots and helped as line back into a Med mooring .

[JPA Cate]

Originally Posted by Pelagic

The issue is not moving it...the challenge is stopping it with wind and current behind you.

Having said that....I did exactly the same thing in 2015 when I towed my 40 ton Stargazer to a refit slip for painting and the engine room gutted.

Short trip but the NE monsoon could fill in early and I would be towing into a long cut with the wind behind me.

I set up a long towing bridal and tied to my tender bow with a slip knot. Outboard was a standard 15hp that was used in reverse.
Me on the tender, my girlfriend steering SG and a helper for lines

Sure enough the wind started to fill in behind me as I entered the cut. But I had preset a large floating poly line to a mooring anchor and did a 180° turn into the wind... let the boat drift over the poly while I they picked up the mooring line.

Worked perfectly as the wind built up to 25 knots and helped as line back into a Med mooring .

^^^^
Now, that was planning ahead!

To the OP, you've had some serious, simple suggestions. When is the great event? Please let us know how it went!

Ann

[TFM]

One person in a rubber dinghy with fairly new 15 HP Yamaha tied to the starboard quarter and one person at the helm of a disabled 33' Beneteau sloop pushed the two vessels at 3 & 4 knots half way across Florida in the Okeechobee waterway. Did not run maximum rpm. Yamaha still functioning superbly after a couple years, but dinghy was worked too hard (loosened seams) and had to be replaced. As said earlier, you might be able to interpolate for your situation. Benign sea conditions would be a plus.