Duck boats with displacement hulls.... Any video under power with heavy chop??

Linhardt

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Being from Missouri, I do not get the luxury to see sneakboats, sneakboxes, etc in the bays. I have always liked the wooden sneakboats, sneakboxes, etc. I envy all you east coasters and the duck boats available and their prices on Craigslist. Some seem like a steal around there. You don't see many good wooden sneakboats around here. Mainly jon boats, Four rivers layouts, etc around these parts. But I can see the use of a good sneakbox in some of the larger lakes around here that may produce some wave action that a jon boat could not handle well in bad weather.

Having at one time owned a Devlin Bluebill (planing hull), I went out a time or two in it. But only tried it on nice summer days, so never really had the chance to see its full potential before having to sell it. Still wish I kept it.

I always hear/read about how well the displacement hulls handle the swells/chop in the bays. Does any one have any good video of some serious weather using a displacement hull duck boat under normal gear load conditions?

With the invention of the drones with cameras, it would be cool to get some outside the boat views of how well it handles the bay.
 
Let me give you my opinion, and it is only an opinion.
Boats were first moved by oar or sail. These boats had to slip though the water with a minimum of effort. The lower power generated by sail or oar required a displacement hull to reach hull speed....a speed dependent on hull length.
These were beautiful boats that slipped through the water with minimum effort. Then someone invented an outboard motor. Now we can provide more power than the displacement hull can use. It actually causes the boat to dig deeper into the water as it tries to rise over its bow wave. My 28 foot sailboat has a theoretical maximum hull speed of about 6 knots. It can reach that speed with just a 12 horse power engine.
With the use of an engine of greater power the boat wants to rise over its bow wave and get onto a plane....much faster. To do this it has to be designed with a hull that will plane or skim over the water. The flat spot in the rear allows this but it sucks power at slow speeds.
That is the trade off. Low power and moderate speed or more power and greater speed. The best combination might be a deep hull or entry to get seaworthyness combined with a flat after section that will allow the boat to plane off.
When you talk about a displacement hull you are really talking about a sailboat hull. Some trawlers also have this type of hull. The will usually have a smaller diesel engine but a hull speed of about 8 knots max.
Hope that helps......Bob
 
Good morning, Anthony~

Bob's reply gives you lots of the science. I have had both types as duckboats - and they both have their benefits. If you need to go far and fast, a planing hull is the way to go - but you will very likely pound over wavetops and drop into troughs and throw lots of spray if there is any wind around. In a displacement hull, the action of the hull is slower and softer. You tend to ride over a big sea and ease down into its trough. One thing I really enjoy about my Sneakbox is the way the round bottom keeps her on her feet - sort of self-leveling - in lumpy seas.

With either type, good seamanship dictates that you match the speed to the seas to find a safe and comfortable ride.

Other benefits are that displacement hulls row and pole worlds better than planing hulls. Rowing a vessel designed for rowing is an efficient pleasure - rowing a planing hull is a chore.

Planing v. displacement aside, there is also the issue of open v. decked over. Wide open boats like jonboats have a high risk for swamping on big waters. The deck and cockpit found on most duckboats provide an effective barrier - keeping errant waves where they belong. A spray dodger is always a good idea, too.

I have no video of my Sneakbox under way - maybe a task for next season.

All the best,

SJS

 
Sorry no video.....but there you have it in what has been said.
I have never felt unsafe in my boat....a very old sail model. I converted it to power. Glass over cedar. Heavy as all hell so a distinct disadvantage is I have to watch the tides. I am not pulling this boat off the mud with no water. I do not go fast. With a 15hp motor I maybe get 8-9kts....with the wind and tide at my back. But....I primarily hunt open water and this boat can go out when a lighter, planning boat cannot. Distinct advantage. I was uncomfortable once. Forecast was a bit off and instead of the 15 to 20 mph winds....it blew steady at about 35mph. Boat handled it and to myself some credit I know how to handle the boat. That right there is something to remember. Know what you can do as well as the boat.
On another note.....I can push through about 4 to 5 inches of saltwater ice which is another advantage.
 
Let me give you my opinion, and it is only an opinion.
Boats were first moved by oar or sail. These boats had to slip though the water with a minimum of effort. The lower power generated by sail or oar required a displacement hull to reach hull speed....a speed dependent on hull length.
These were beautiful boats that slipped through the water with minimum effort. Then someone invented an outboard motor. Now we can provide more power than the displacement hull can use. It actually causes the boat to dig deeper into the water as it tries to rise over its bow wave. My 28 foot sailboat has a theoretical maximum hull speed of about 6 knots. It can reach that speed with just a 12 horse power engine.
With the use of an engine of greater power the boat wants to rise over its bow wave and get onto a plane....much faster. To do this it has to be designed with a hull that will plane or skim over the water. The flat spot in the rear allows this but it sucks power at slow speeds.
That is the trade off. Low power and moderate speed or more power and greater speed. The best combination might be a deep hull or entry to get seaworthyness combined with a flat after section that will allow the boat to plane off.
When you talk about a displacement hull you are really talking about a sailboat hull. Some trawlers also have this type of hull. The will usually have a smaller diesel engine but a hull speed of about 8 knots max.
Hope that helps......Bob

Yes and one thing not said explicitly - many people push displacement hulls over the bow wave and force them to plane on the very short flattish rear portion of the hull. If a small boat is travelling more than 5-6 knots is not being used as a displacement hull.
 
Another thing to add is that most traditional glass over cedar sneakboxes being built today, and it is a dying art unfortunately, are planing or semi-displacement. Many of the sneakboxes seen on this website over the years are really semi-displacement hulls vs. a true sailer that's been converted or older style rowing hull. The biggest advantage to any one of these hulls is the ability to slow it down and ride out heavy weather. Invaluable in the kinds of conditions we often find ourselves in.

As for video of this.... as both a sneakbox and drone owner I think one of the last things I'd want to be doing is running my boat in heavy weather and trying to film with the drone.
 
Another thing to add is that most traditional glass over cedar sneakboxes being built today, and it is a dying art unfortunately, are planing or semi-displacement. Many of the sneakboxes seen on this website over the years are really semi-displacement hulls vs. a true sailer that's been converted or older style rowing hull. The biggest advantage to any one of these hulls is the ability to slow it down and ride out heavy weather. Invaluable in the kinds of conditions we often find ourselves in.

As for video of this.... as both a sneakbox and drone owner I think one of the last things I'd want to be doing is running my boat in heavy weather and trying to film with the drone.

And here I was thinking you were just the man for the job - tiller in one hand, seas 4-6 feet, operating the drone in the other. :).
 
I think I am starting to understand now. I have always been around jon boats and others with planing hulls and not around or operated sailboats or the likes with displacement hulls. So didn't have real world comparison.

As for video of this.... as both a sneakbox and drone owner I think one of the last things I'd want to be doing is running my boat in heavy weather and trying to film with the drone.

What I meant by using the drone I was thinking more of someone else doing the videoing with the drone and not the boat operator. Thought that with the drone it could easily move around and above the boat as it was underway. Besides I kind of like watching those types of videos of boats done that way. I do not condone drone operation while operating any type of boat, vehicle, machinery, etc. :)
 
I am working at digitizing a bunch of our videos and I have some footage of our 12'4" South Bay Scooter under power in some chop in Lake St. Clair. Once I get the digitizing edited (using Nero), I can email you some video. Bunches of the other videos from Sculling the Brant II to our painting videos (Open Water colors & camo) will be on YouTube soon.
Holler with any questions and send me your email when you get a chance.
Lou
 
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