Sea Sled madness. It’s in my brain.

I guess this picture is pretty telling.

Pretty flat bottomed. Perhaps they are a bit rough riding and that might explain their limited popularity?

 

Roughly 100 square feet of window. In acrylic ¼" thats 153#.

 

It seems like that to me too. But the few fellows who made and had them that I could actually talk to said they worried about that too. But under way, the turned in bows turn the bow waves inward instead of out, and the boat lifts up and rides on the aerated water and bubbles. They said. The guy at Winninghoff boats is in Massachusetts, and Marcus Lee is in Sitka Alaska. Can't go see either.

 

This picture is the best I've found of a sled at speed. I wish I could see more of the wake. But note the undisturbed water on the near side, all the way from the entry of the near side keel, all the way to the transom. Compare that with a similar view of a conventional hull at speed.

And that aerated water in the tunnel. All of that goes out under the transom. Viscous drag of air is 1/800 that of water.

 

This boat is no slug. Fast, powerful, supremely seaworthy. How much kinetic energy is in that disturbed water?

And the kinetic energy fairies don't supply that stuff. The guy at the fuel dock does.

 

The shapes of the outer side of the sea sled are much more vertical than those of the work boat in the second picture. Therefore, the bow wave of one and the other cannot be compared. On the other hand, if the stern central wake of both boats can be compared. What do you think represents a greater waste of energy and why?
I do not want to raise controversy. It's just an innocent question since I don't know anything about sea sleds.

 

Thanks for the question, TANSL.

The sea sled doesn't really have a stern central wake, since the transom is dead flat. But in this picture the boat, Miss Lakeside, has a single huge surface prop, lifting a large cloud of mist. It's about a 2' prop on a 26' boat.

The brilliant empirical planing boat NA George Crouch, by examining many boats directly, developed his Crouch formula. He had constants for different planing boats. Ranging from 150 for a typical planing craft, to 230 for a sea sled. Since it's a factor in the calculation, that's 50% more speed for the same power and fuel consumption. I think these 2 photos explain why. But I honestly don't know. Like every single other guy on this forum, I've never seen one in real life.

 

Yet. And then I hope all of you fine gentlemen and ladies will come for a ride. Bring your GPS and accelerometer too, have a drink on me. WE NEED HARD DATA!

 

My bad. Of course there's a stern central wake. It isflattened, and mostly bubbles, but the water displced by planing must rebound.

 

Anything that moves large amounts of water, even with bubbles, results in loss of thrust. But who knows?, experience will tell. Good luck.

 

This has to be about the most interesting build thread on the internet just because nobody knows exactly how it's going to turn out.

I salute you for undertaking this... it's a hell of an experiment. I hope you get the performance you're expecting and more.

 

Thanks... Cracked? Call me DC. I'm pretty stoked. There's a huge amount of history that we just can't reach. Not with concrete performance numbers. I want those numbers.
Welcome to the forum, by the way. Like everything else, we have good and bad. But there are folks on here that will offer advice that you could never pay them for, because they are so good, they're too busy for anymore clients. I hope you really enjoy the forum. I sure do.

 

what year were the seasleds originally built? I have old magazines. Lots of them. Maybe I can find an article.

 

1914, in production to the early 50's

 

Thanks - I very rarely post here but have been reading the posts for years; very interesting information gets passed around here.

I just build boats for fun and have only designed a little skiff and a sharpie sailboat, myself, so I don't usually comment.

But this thread has been very cool the whole way along. I'm extremely curious to see how it all turns out.