Large tender onto sundeck?

I'm going to buy a 40-50ft trawler for liveaboard that can act as a roaming fishing mothership. I currently have a little 14ft CC catamaran skiff (Twin Vee) with a 50hp. It's an awesome 1 man setup (and decent for 2); it handles offshore on calmer days and can float over shallow flats.

I can't really imagine being able to go smaller than that. Claimed dry weight is 650 -- so obviously in the 1000+lb range with motor and basic gear. Curious if it'd be feasible to occasionally davit winch a boat that size onto a 40-50ft Trawler sundeck (or bow)? I imagine it'd be more doable on a 50 than a 40, so that's why I'm asking because if so, I'd be more inclined to buy a trawler on the large end of my size range.

My 41' President tender on the bow has a weight limit of 300 lbs which is lifted by a crane. I think the design needs to be verified by the mfg.
I have an 11' AB Aluminum hull RIB with a 20 HP 4 stroke Merc outboard.
I remove all gear prior to launching including gas tank and dive gear.

I would not want to put that much weight up on the top of my sundeck due to how much effect it would have on stability. Maybe on a 50’ boat.

You said "I'm going to buy a 40-50ft trawler..." but no hint of year, semi or full displacement, etc. Creating this capability in a new build is probably more easily solved. Doing it with at 30 year old boat is another matter entirely. Besides the physical space issue, you have whether the various decks can support the weight of the tender and the crane. And what it does to your boat's stability.

In this video:
The hosts talk about their boat's refit of the boat deck, including structural changes they had to make. Might be of interest to you. Good luck and happy fishing!

JustBob said:

Creating this capability in a new build is probably more easily solved. Doing it with at 30 year old boat is another matter entirely.

Click to expand...

It's gonna have to be a 30 year old boat.

ERTF said:

It's gonna have to be a 30 year old boat.

Click to expand...

(If this tender setup is your #1 priority) I think I would try to find a marine architect or two that knows this kind of work, and have them suggest the boat to look for.

Figured first step would be to see if anybody here chimes in that they do something similar -- and then take note the size/make of their vessel & tender system. I've seen 13 ft whalers on sundecks and bows, so it's not a total fantasy out of left field.

I've seen several fishing boats out of Spanish Wells towing up to 6 fishing boats at a time in remote areas, like Cay Sal. This solves both the storage issue and the inevitable issue of lifting a largish boat in heavy seas. And these guys have 50/60 footer mother ships. Just another idea.

Yeah I know it's possible to tow. I was just thinking in situations like locks or docking particularly single-handed, it would be really nice to have the option to not have to worry about the skiff behind me. Also possibly preferable for a Bahamas crossing.

A 13.5’ Avon, center console with a 50 hp 2 stroke came with Hobo. Total weight was over 600 lbs. Lowering and raising her off the boat deck was an experience. The previous owners had her for 10 years and never had any issues. We sold her for something a little lighter but it worked for them.

On our 90 footer we have a 19 foot inflatable tender with a 90 horse
it weighs over 2000 lb
When bringing in the tender the big boat lists about 5 degrees making it a two man job to swing in.
Also you have to make sure the tender is tied down tight
Even in the nicest weather
Things go bad quick and I have seen it rise off the chocks a foot in rollers off of Campbell River.
Personally we only needed a 15 footer

How about an aluminum hulled RIB? For example you can get a 14' AB aluminum hull RIB with console that weighs 367 plus motor. If you can do without the console you can drop down to 247lbs for the same size boat.

We had a 13ft Rendova with a 40 hp Yamaha on the boat deck of a 60 foot boat. About 1000 lbs. It is doable but requires two people to launch and retrieve. Forget it if there is significant wind/wave action unless you want your dinghy come through the saloon windows. Make sure your tie downs can handle the substantial forces when you get into some bad weather. We know a couple that lost their heavy dinghy from the boat deck crossing Georgia Strait. Did quite a bit of damage as it fell into the cockpit and then overboard. The captain was busy keeping the boat from broaching and could not deal with the loose dinghy.

RIBs just aren't setup for fishing at all, plus a 14' RIB wouldn't have close to the space of my little cat (which is already a very compact fishing platform). Also, with motor and everything, it's still gonna weigh close to 700lbs, so I don't see a big weight payoff for all that sacrifice.

I travel on a 52' sportfish(lot of open space on the bow) that we carry a 13' Boston Whaler on the bow. The boat came from the factory with a 1000 lb crane and the Whaler is probably pushing that limit. As stated, the boat will list some when loading and its a 2 man job. And definitely not a job that you would attempt in rough weather.

This will work:

I'd have a very good yard or a naval architect weigh in on a specific boat you are interested in. We launched a 13' Whaler off the boat deck of an 18'2" beam Hatteras frequently for many years; it caused almost unnoticeable list and I even did it my klutzy self a few times. In bad conditions, I found retrieving to be much more of an issue than launching, logistics-wise. I knew some folks with 15'10" beam Hatteri that also launched Whalers and notice 2 things: list was more pronounced, and a 13 footer extended beyond the boat deck some. Keep beam in mind more than length! But in each case the boat deck was designed to support a 1000# + tender.

A mates 65 fter carries 21ft with a 150 up top, he reckons roll is reduced in a seaway.

Apparently displacement hulls can carry a load up high

I carry a 1000lbs dingy (12’ rib/60hp Suzuki). I have a 2000lbs crane which makes quick work of launching and recovering. The dingy use 5 quick lock straps that lock her sown tight enough to take on any conditions I can handle. Problem is my boat is in the 50-60 foot range.

Think it is no problem

ERTF said:

I'm going to buy a 40-50ft trawler for liveaboard that can act as a roaming fishing mothership. I currently have a little 14ft CC catamaran skiff (Twin Vee) with a 50hp. It's an awesome 1 man setup (and decent for 2); it handles offshore on calmer days and can float over shallow flats.

I can't really imagine being able to go smaller than that. Claimed dry weight is 650 -- so obviously in the 1000+lb range with motor and basic gear. Curious if it'd be feasible to occasionally davit winch a boat that size onto a 40-50ft Trawler sundeck (or bow)? I imagine it'd be more doable on a 50 than a 40, so that's why I'm asking because if so, I'd be more inclined to buy a trawler on the large end of my size range.

Click to expand...

The previous owners of our boat used to carry a 4-person helicopter on the sun deck of our boat. Look in the archives Nader ocean Alexander with help to see a pic.

The PO of my boat had a 14' Novurania GRP hulled RIB, with Yamaha 50. I think it was about 800#. His davit was 120VAC, which lifted fine but was manual (uncontrolled) rotation. That led to some 'interesting' and at times dangerous wild swings of the RIB.

I could not change his old winch to 230VAC /50Hz. So now I use a Nick Jackson davit rated at 1500#. It has a 12V winch with hydraulic rotation and hydraulic ram lift on the boom also. My current tender is a 14' AB RIB, with aluminium hull and a Honda 40. It weighs a bit less the the old rig. The RIB fits fine on my 50' boat, and the weight is not a problem at all on the 'boat deck' above the salon. With hydraulic rotation it is a safe and easy one person job to launch and retrieve the RIB.

Damn spell check

Gordon J said:

The previous owners of our boat used to carry a 4-person helicopter on the sun deck of our boat. Look in the archives Nader ocean Alexander with help to see a pic.

Click to expand...

Should have read: look under archives , Ocean Alexander with helo, filed under the ocean Alexander section