Towing a Tender

[Bill Lee]

I'm wondering about any of your experiences towing a tender. I typically cruise the 'mothership' (a 42' Silverton convertible) at 21 knots and was thinking of towing a 15'-17' boat (maybe a Boston Whaler or Scout with a 75 hp motor). I cross the Georgia Straight from Vancouver to the Gulf slands regularly and it isn't always calm. Any experiences with:
1) types of harness/bridles
2) tow boat motor up/down
3) effective length of bridle
4) how hairy does it get in rough seas
5) anyone lose or damage a tender doing this
6) should I know anything else????
7) how much impact on fuel burn?
Cheers,
Bill

[skipmac]

Towing a large tender at high speeds in rough seas = big problem.

Possible consequences: sunk tender, eyes and cleats on the tender ripped out, cleats on the towing boat ripped out, whiplash injury to passengers from the broken tow line.

Have towed smaller dinghies in moderate conditions at slower speeds and had problems. Lost one dinghy, lost one outboard, ripped towing rings out of the dinghies.

I think you can guess that I think it is not a good idea.

[Vasco]

The crewed charter motor yachts plying Bahamian waters regularly tow center console fishing boats now. Some are 30 feet long with two or three very powerful outboards. Towed on a long, long line attached to a very strong point.

[Blue Stocking]

Originally Posted by Vasco

The crewed charter motor yachts plying Bahamian waters regularly tow center console fishing boats now. Some are 30 feet long with two or three very powerful outboards. Towed on a long, long line attached to a very strong point.

Number of them here this summer.

OK if mother ship engines necessitate 20" exhausts.
Saw a Merritt take $7800 of fuel.

[imagine2frolic]

I don't know your area but you see it daily in the Bahamas, but as Vasco described. Attatchment points, and a very long line are extremely important.........i2f

[Bill Lee]

OK,
I think I have 2 hints: strong attachment points and long line. Thanks. any other info?
cheers,
Bill

[CharlesFCook]

This may be helpfull.

Yachts standards for towing tenders vary | The Triton

[HappySeagull]

Long,strong and ,well,..towed a herring skiff ok with Polypropylene hawser.(not hardwarestore looselaid too-small garbage)It floats. But we also used a cannonball lead weight to make a catenary and help straighten the tow if it surfed...towing is unpleasant,whatever.

[Rakuflames]

Originally Posted by Bill Lee

I'm wondering about any of your experiences towing a tender. I typically cruise the 'mothership' (a 42' Silverton convertible) at 21 knots and was thinking of towing a 15'-17' boat (maybe a Boston Whaler or Scout with a 75 hp motor). I cross the Georgia Straight from Vancouver to the Gulf slands regularly and it isn't always calm. Any experiences with:
1) types of harness/bridles
2) tow boat motor up/down
3) effective length of bridle
4) how hairy does it get in rough seas
5) anyone lose or damage a tender doing this
6) should I know anything else????
7) how much impact on fuel burn?
Cheers,
Bill

I have seen people tie fenders in the center of dinghies in a pyramid shape. Supposedly it helps right the dinghy if it has flipped over. I urge you to hang your motor on the stern of your pulpit on a motor mount. I have seen dinghies flip with motors on 'em and it ain't pretty. Also much harder to right.

I would certainly use more than one painter, but watch the length. If a wave pushes your dinghy up close to your stern, you don't want that painter long enough to get around your prop.

[Bill Lee]

Thanks for the Link - which I've seen before and resulted in my starting this thread. The link was an article for big (BIG!!!) yachts towing large tenders and didn't clarify at what speeds. I have a smallish boat (42' lwl) and towing a smallish tender (16-17') at 21 knots (or so). Not a lot of info out there about this.

[Mardav]

Originally Posted by Bill Lee

OK,
I think I have 2 hints: strong attachment points and long line. Thanks. any other info?
cheers,
Bill

check out toweye.com for some good info. I regularly tow my 20' Shamrock, but at slower speeds for the most part. I typically tow with about 75' of plasma at 12 knots, but at 17 (I don't go much faster!) I find I need to double the scope to get the tender on the sweet spot. I towed a 13' Whaler for years whith a prior boat and the only advice I have on the Whaler is build a 'hard point' in the bow for the toweye as the double hull with foam makes it difficult to put a back plate on the eye. Whaler doesn't put any wood there and the forces tend to pull the backing plate right through the inner hull where the load is very concentrated (this is one of those 'don't ask me how I know' things) at just the wrong time.
Good luck, love those Whalers!

[Bill Lee]

Thanks Mardav,
Great website and great information. I'll contact toweye and ask them about towing at 19-21 knots for a 17 foot boat weighing about 1600 - 200 pounds wet. The infomation on toweye.com doesn't give an indication of issues at those speeds although some of the pictures on the site look like rough seas at slower speeds or alot of splshing and plowing at faster speeds. Cheers,
Bill

[GordMay]

Originally Posted by CharlesFCook

This may be helpfull.

Yachts standards for towing tenders vary | The Triton

That WAS helpful.

See the related article
Towing tenders: What hardware do you use? | The Triton

[Bill Lee]

Thanks Gord,
I have read both those articles before but I still have little information regarding problems arising in towing at the speeds I'm hoping for. I've sent an email to toweye and am awaiting that response - which I'll summarize and post if received. Cheers,
Bill

[Triggerfish23]

Bill,

Here's my experience if you're still interested.

We towed a 26' aluminum boat behind the 100' yacht that I ran. Much of the time we towed at 17 knots and if we weren't, we were cruising at 12 knots. We used a 1 1/4" synthetic tow line. You will want something with stretch. Depending on the direction (relative to our direction of travel) and frequency of the waves, there were days I could run 17 knots in 4'-5' seas with no issues.

1) types of harness/bridles
Obviously, there are issues with towing at speed and the drag of the vessel being towed. The largest issue is going to be the strength of the eye and the material (presumably fiberglass) surrounding it. My advice would be to try to strengthen the eye if possible and disperse the load. If you have the ability to hide the backing (depending on your model, this may not work), I would suggest having a shop make you an aluminum plate that the eye screws through.

If you have stronger breast cleats than a tow eye, I would recommend making a bridle that leads to the eye (in case the eye comes out) or going straight to the cleats. I don't feel that the hardware on many of the cleats allows for much pulling especially in a shearing direction, so it wouldn't be my first choice.

2) tow boat motor up/down
I noticed someone suggested pulling the motor off. I don't think this is smart or practical for your size tender. I would leave the motor on to help keep the weight in the back of the boat and the bow up. However, you should pull it up and lock it in the 'up' position. In lumpy seas the motor will bounce around and you don't want the ram taking all of the shock if you can help it.

3) effective length of bridle.
This can vary from boat to boat both on the towing and towed ends. I would say the absolute least amount of line would be 100'. I think I would plan for between 150'-200'. Regardless of how much you are actually using most of the time, you may want to keep the rest around in case you get into rough seas and need to add some line. I would say you should fashion a quick coupling of some sort so that you can insert it quickly and easily.

4) how hairy does it get in rough seas
It can get very hairy in rough seas and it means that you: a) try not to travel in rough seas and b) drive your main vessel by paying close attention to both boats and ensuring that you aren't towing your tender through waves or jerking on it too hard.

One way to accomplish this is to add weight (a large downrigger ball or something like it) to the middle of your tow line. This provides a shock absorber in between the two boats. The issue in rough seas is that the boats aren't moving in unison and the larger boat wins. When it does, it makes the tender do things (usually bad things) that it doesn't want to do.

7) how much impact on fuel burn?
I wouldn't worry about your fuel burn too much. At those speeds, you aren't winning any arguments with electric car owners. The tender will be on plane and I wouldn't think that you would notice much more than a 10 gallon difference on a weekend. Clearly, all boats are different and you would have to do extensive testing, but I doubt you will notice unless you really pay attention.

I have had a tow eye rip out of the aluminum tender when towing. It's a pretty easy fix because aluminum isn't overly pretty to start with. I just thought it was worth pointing out that tow eyes really aren't made for huge amounts of strain. If you can, you should reinforce it.

I also recommend that you continue to keep an eye on the boat. If it starts doing something it hasn't before, start asking why. Try to learn it's habits as you've done with your Silverton so that you know when something doesn't seem right.

I hope that this has helped clear some things up for you. There are some items that I didn't address that you've probably thought of. I would be happy to continue this discussion either online or off if you would like to go over it some more.

Good luck and safe boating,

Trig