Speed when towing a dinghy

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Warren Kaplan

Speed when towing a dinghy

Post by Warren Kaplan »

I've been looking at all those great pictures of the Cape Dory NE Fleet Rendezvous which I sadly missed this year. Obviously just about everyone was towing a dinghy. Either a hard dinghy or an inflatable one. I have never had the occasion to tow a dinghy, but that will be changing next year. Forgive these elementary questions, but the more I know the better I feel. What effect on boat speed does towing a dinghy have? Does it make a difference whether the dinghy is hard or inflatable? Also, does it affect boat handling? Is there a problem with towing a dinghy sailing before the wind with a following sea? Anything you can tell me about this subject I would appreciate.

Thanks as always
Warren Kaplan
S/V Sine Qua Non
CD27



Setsail728@aol.com
zeida

Re: Speed when towing a dinghy

Post by zeida »

Warren:
Towing a dinghy is one more compromise, of which there are so many in sailboats. If you are cruising, there is almost no choice but to carry one, whether you tow it or carry it on board, from davits in the stern or up on deck. The CD's do not like to have excess weight in the stern, so that sort of limits your carrying location. I have the CD-33 Bandolera II and when I want to really go out sailing for the day, I leave the dinghy behind. It does make a difference in speed, although not that much. A hard dinghy will put dents on your hull every time you come close to it, unless you have some kind of all-around soft rubrail that can protect the boat while the dinghy bumps against it. There is no escaping from this. An inflatable is less of a problem. You have to plan how and where you will board your dinghy, if from the boat, and viceversa, so you can have fenders on the dinghy to stop the bumping. Even an inflatable will put dents on the hull, since the oar locks are not rubber. Towing a dinghy needs getting used to. Very easy to have the tow lines/harness get tangled up in your prop/shaft! Just happened to me! Fortunately I was able to dive and unwrap the mess!
Having the dinghy gives you access to many places where you can not normally get to in the sailboat. It is also added security. If you're towing a dinghy and something really goes wrong with the sailboat, you have a lifesaver in your dinghy. I keep an "emergency survival kit" in the dinghy, just in case. So there are many advantages to having it. Mine is an 8 ft. Carib with a 4/stroke, 4 hp Yamaha outboard. Not fast, but it serves my purpose and works very well. I had to install a Forespar outboard hoist to help lift/lower the engine from its regular position at the stern pulpit to/from the dinghy. My outboard weighs 49 lbs. and the hoist works very well. I installed it myself with a friend, just following easy directions.
Almost every cruising boat, everywhere, needs a dinghy. It is a fact of sailboat life. An inflatable, if need be, can be partially deflated and carried on board, to be inflated at the destination, or when needed. In case of a storm, (we are in Florida) it is easier to stow in a garage. The footpump on mine, I find is very easy and efficient!

No matter where you are sailing, if you are going cruising, not racing, you will be better off with a dinghy at your side.
Regards,
Zeida
Bandolera II




zcecil@attglobal.net
Bob Pence

Re: Speed when towing a dinghy

Post by Bob Pence »

Warren Kaplan wrote: I've been looking at all those great pictures of the Cape Dory NE Fleet Rendezvous which I sadly missed this year. Obviously just about everyone was towing a dinghy. Either a hard dinghy or an inflatable one. I have never had the occasion to tow a dinghy, but that will be changing next year. Forgive these elementary questions, but the more I know the better I feel. What effect on boat speed does towing a dinghy have? Does it make a difference whether the dinghy is hard or inflatable? Also, does it affect boat handling? Is there a problem with towing a dinghy sailing before the wind with a following sea? Anything you can tell me about this subject I would appreciate.
I have towed a dinghy for 16 years from Bedford, Ma. to Florida numerous times behind a CD30 K, a Pearson 365, a CD 36 and a Pilgrim 40 trawler. Never a major problem. Inflatable is best with RIB or folding floor then you can literally jump from the deck into the dinghy. Had a Dyer sailing dinghy with the Pearson, towed it most of the time and on deck crossing over to the Bahamas. Use polyethelene floating tow line and avoid getting it in your prop and/or string a couple of floats on the tow harness. In following sea longer towline or bring nose of inflatable up and out of water to stern deck. Never found speed of boat to have any effect on dinghy. Always felt dinghy slowed boat a 1/2 knot but that's subjective, only on flat water with no wind could a real judgment be made. Don't ever count on the dinghy as a life raft. I would never leave the boat until I was on top of the mast and the boat still going down.Bring dinghy up tight to stern when in a marina and until you are clear, they always want to go under the dock. I was Captain on the Tow Boat U.S., Early Bird, at the River Forest Marina in Belhaven, N.C. and towing big boats wasn't much different.
Warren Kaplan wrote: Thanks as always
Warren Kaplan
S/V Sine Qua Non
CD27


sixpence@dmv.com
Ken Cave

Re: Speed when towing a dinghy

Post by Ken Cave »

I have been using a little six foot Quick Silver with a plywood floor and blow up rib in the center to make a bottom a "V" bottom, and have used this on two sailboats with excellent results. It weighs about 60 pounds, and I have no problems in carrying it down the ramp to the marina when I intend to make more than a day trip.

With the "V" bottom, it will actually plane behind your sailboat and have little effect on the speed.

I use a 3.3 Mercury on it, and, believe it or not, I can actually plane this dinghy if I sit in the pointy end!!

The only negative thing on this kind of dinghy is the floor-you cannot pull it up on the shore without destroying the bottom. I added some wheels on the stern which has helped a lot, but you still cannot land your passengers on the beach.

To preserve it, I paint the bottom once a year with a rubber paint. This shows if I have any potential problems-scuff marks, gouges, etc

Although it says it will carry only two people, I have had four adults in a storm (not my choice) without any problems other than getting our fannies wet!

As the folks above state-get an inflatable!! They also make a wonderful bumper between you and the dock if you really screw up!!

Ken Cave
Cape Dory 28 #227



bcave@whidbey.net
Boyd

Re: Speed when towing a dinghy

Post by Boyd »

Hi Warren...

You said that you use a polyethelene towing line to avoid getting it into the prop... I managed to suck one of those into my prop during docking and didnt enjoy the experience. I find out the hard way.. like you said the only sure way to keep the line out of the prop is to shorten it till the dingy is almost touching the stern when maneuvering in a marina. In open ocean I ease the line out. Learned that one the hard way.

I tow an inflatable and cant detect any change in boat speed with it behind.

Boyd.

Bob Pence wrote:
Warren Kaplan wrote: I've been looking at all those great pictures of the Cape Dory NE Fleet Rendezvous which I sadly missed this year. Obviously just about everyone was towing a dinghy. Either a hard dinghy or an inflatable one. I have never had the occasion to tow a dinghy, but that will be changing next year. Forgive these elementary questions, but the more I know the better I feel. What effect on boat speed does towing a dinghy have? Does it make a difference whether the dinghy is hard or inflatable? Also, does it affect boat handling? Is there a problem with towing a dinghy sailing before the wind with a following sea? Anything you can tell me about this subject I would appreciate.
I have towed a dinghy for 16 years from Bedford, Ma. to Florida numerous times behind a CD30 K, a Pearson 365, a CD 36 and a Pilgrim 40 trawler. Never a major problem. Inflatable is best with RIB or folding floor then you can literally jump from the deck into the dinghy. Had a Dyer sailing dinghy with the Pearson, towed it most of the time and on deck crossing over to the Bahamas. Use polyethelene floating tow line and avoid getting it in your prop and/or string a couple of floats on the tow harness. In following sea longer towline or bring nose of inflatable up and out of water to stern deck. Never found speed of boat to have any effect on dinghy. Always felt dinghy slowed boat a 1/2 knot but that's subjective, only on flat water with no wind could a real judgment be made. Don't ever count on the dinghy as a life raft. I would never leave the boat until I was on top of the mast and the boat still going down.Bring dinghy up tight to stern when in a marina and until you are clear, they always want to go under the dock. I was Captain on the Tow Boat U.S., Early Bird, at the River Forest Marina in Belhaven, N.C. and towing big boats wasn't much different.
Warren Kaplan wrote: Thanks as always
Warren Kaplan
S/V Sine Qua Non
CD27


Tern30@aol.com
Chris Scheck

Life with Dinghy

Post by Chris Scheck »

To emphasize the advice you've already gotten -

A dinghy does give you more flexibility in going ashore. However, most of the more popular cruising destinations have a launch service until about 10 pm during the summer, so if you're willing to pay a couple of bucks per person, you can spare yourself the aggravation of towing a dinghy. Unless you're a really careful captain, you're going to find that some of your most embarrasing moments afloat are caused by the dinghy. As other posts have noted, lots of people get the dinghy painter (towline) caught in the prop. Of course, CDs are less likely to have this happen than other boats because of the attached rudder. But a fouled prop is far from the only problem you will have with a dinghy. Let me list a few things that have happened to us. If your reaction is, hey I'm not stupid, that would never happen to me, well, good for you. However, EVERY ONE of these calamities has befallen me over the past 30 years ...

1) The dinghy drifts under the dock and behind a piling while you're getting fuel for the big boat. When you pull away, the dinghy is caught, the towline stretches tight as a guitar string, and rips the bow eye out of the dinghy! Causes much mirth and merriment on the fuel dock.

2) You make a tight turn around a channel buoy or mooring ball, the dinghy gets caught on it, and almost rips the bow eye out! Not as bad as #1, but everyone at the club knows what happened because you have red, or green, paint on the bow of your dinghy.

3) You tie the dinghy to a fixed pier (not a floating dock) and go into town for the day. The wind changes, the dinghy drifts under the pier, and the tide comes in. You come back to find your dinghy and motor under the dock, submerged. Also, you can't get it out from under the dock until the tide goes out again!

4) You're trying to lift a heavy motor (4 hp or more) from the dinghy to the boat. A wave rocks the dinghy, you lose your balance, and rather than go into the drink yourself, you let go of the motor and it goes the bottom. This can be prevented by tying a safety line to the motor.

5) You're towing the dinghy offshore and a stiff breeze comes up. Waves reach 6-8 feet and the dinghy looks like a surfer off Maui. After an hour or so, it pitches down a wave and flips over. In very rough seas and high winds, some people have cut the dinghy loose and gone on rather than try to recover it. A less serious variation of this is that the gas tank flips over inside the dinghy as you're towing it, and all the gas slowly leaks into the dinghy thru the vent hole. A real mess to clean up.

6) The final indignity (aren't you glad it's over?) You dinghy into a secluded spot on say, Martha's Vineyard, beach the dinghy and walk into town. You come back and ... no dinghy! This can't happen on the Vineyard ... this isn't New York City! Believe me, it is really hard to enjoy the rest of your vacation when you've just lost $3000 worth of dinghy and motor. Now we carry not just a lock, but a 6-foot bike cable and an old piece of standing rigging with eye-terminals at both ends. That will usually reach from the dinghy up the beach to a tree or piling.

Now, what about the bright side? Well, most sailors (especially kids) will agree that dinghying around a new anchorage is one of the most fun things you can do on the water. A very social friend of mine pointed out that "it's really easy to make new friends when you're in a dinghy!" In fact, I could probably sell the big boat, keep the dinghy, and still have 50% of the fun I get from boating for a fraction of the cost.
To sum up ...
Hard dinghy (like a Dyer) ... prettier, tows and rows better, no
maintenance.
Inflatable dinghy ... much more stable, more
comfortable to sit in, can leak, generally looks terrible
after a few years in the sun

A final word ... if you do get a dinghy, you don't have to take it with you ALL the time. If you're going to a place with launch service, leave the dinghy at home occasionally. It feels great to go for a sail without something hanging off the transom.




cscheck@aol.com
Neil Gordon

Re: Speed when towing a dinghy

Post by Neil Gordon »

>>What effect on boat speed does towing a dinghy have?<<

If I was racing, I wouldn't tow one. But cruising, I'm not sure you'll notice the difference.

>>Does it make a difference whether the dinghy is hard or inflatable?<

An empty inflatable will plane with no effort. If you tow a displacement hull behind you, you'll be suject to its limitations on hull speed unless you can get it to plane. That takes more energy and will cost you more speed. As others have said, inflatables come with built in fenders... they're easy on the hull.

We tow an inflatible and have no trouble getting from the dinghy to the boat at the stbd gate without a ladder. It's easier than using the stern ladder.

I use two poly painters when towing, keeping the dingy up close to the transom when pulling in/out of the slip, then letting some line out for cruising. The dual painters keep the bow of the dinghy square to my stern and give me the peace of mind that if one parts, I haven't lost the dinghy.

For a number of reasons, I wouldn't rely on a launch service in lieu of having a dinghy. You never know when you might have a change of plans, due to weather or otherwise, and find yourself moored or anchored without transport to shore. Or maybe the yacht club launch is just out of service that day. For me... I have a pup who wakes up way before the time the launch service starts running.

Other advantages of a dinghy... if you find yourself grounded... it's lots easier to row a kedge out than to swim one out!

Just be careful towing any dinghy in heavier seas or higher winds. They can swamp, flip, etc. An inflatable will be less likely to swamp but more likely to end up plastered against the back stay.


Regards, Neil
s/v LIQUIDITY
Cape Dory 28 #167

Also, does it affect boat handling? Is there a problem with towing a dinghy sailing before the wind with a following sea? Anything you can tell me about this subject I would appreciate.
Warren Kaplan wrote: Thanks as always
Warren Kaplan
S/V Sine Qua Non
CD27


cdory28@aol.com
Larry DeMers

Re: Speed when towing a dinghy

Post by Larry DeMers »

Warren,

We have two dingies..a plywood nesting pram that I would like to sell, and an Avon RollAway inflatable. The inflatable tends to plane off easily while being towed, so I feel that we may sacrifice 1/2 kt. to her. The nesting pram however takes a full knot anyway.

When moving around at greater than normal distances from home, take the dinghy out of the water and stow it..or;

While being towed, the sea conditions can make life miserable for the dinghy and sailor. With an inflatable, high winds tend to make the dinghy become airborne, spinning them like toy props on someones beenie..if you remember that example. Our heavier wood pram likes to gather rainwater, and will be subject to being a battering ram unless you place her on the rising part of the second or third wavefront behind you. This will ellicit a constant pull rather than a yank and a mad slolom down the wave front, right into your stern.

We simply deflate our Roll Away, roll it up and stow it on the cabin roof in a box that holds it securely. It is a 20 minute job (honestly) to pump her up and launch her..but could be done in 10-15 if there were enough incentive to do so.

On painters, the myth that a floating polypropelene line will prevent sucking the painter into the prop has fooled many a sailor, and I have some rather funny video showing one such occasion..the dinghy painter wraps around the shaft, and the WalkerBay GRP dinghy gets pulled into the prop and the fiberglass can be heard to be munched up at a prodigious rate. This was on a C&C 27, not a CD. He had gunned the engine to set the hook, and the large swirl included so much air that the polypropelene line sunk in the frothy water/air mix, and was suucked into the prop.

To cure this, we use a 50 ft. double braided non-floating painter, 3/8 in. diameter. 6ft. from the ships end, we tied in an 8in. loop to go around the starboard aft mooring cleat while doing any slow or possibly reversing engine work such as anchoring, docking, rafting up etc. There is also an 8in. loop tied into the painter, at the distance where the boat will ride on the uphill portion of the second wave at cruising speed. This makes the length of the painter unambiguous, and easily and quickly adjusted. We tied these knots 10 years ago, and they are still there, same place. Jeesh for variety sakes..maybe we ought to buy a new line or something?!

Cheers!

Larry DeMers
s/v DeLaMer
Cape Dory 30

Warren Kaplan wrote: I've been looking at all those great pictures of the Cape Dory NE Fleet Rendezvous which I sadly missed this year. Obviously just about everyone was towing a dinghy. Either a hard dinghy or an inflatable one. I have never had the occasion to tow a dinghy, but that will be changing next year. Forgive these elementary questions, but the more I know the better I feel. What effect on boat speed does towing a dinghy have? Does it make a difference whether the dinghy is hard or inflatable? Also, does it affect boat handling? Is there a problem with towing a dinghy sailing before the wind with a following sea? Anything you can tell me about this subject I would appreciate.

Thanks as always
Warren Kaplan
S/V Sine Qua Non
CD27


demers@sgi.com
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