HIGH SPEED, SMOOTH RIDING WATER CRAFT

   I haven't worked on the ground effect vehicle model in quite some time. But a new idea has been brewing in my mind. The night of the 17th-18th was a sleepless one. (partly owing to a nasty acid reflux that just wouldn't end!) Vague ideas started firming up as I lay awake thinking about it.

   I have long been attracted to the idea of flat bottom catamarans, ever since I saw one planing under sail in a sailing magazine picture in the 1980s - a 12 foot long sailboat doing 20 knots. That seemed ideal. A sail couldn't have that much power, yet the boat was skiing over the water.
   Now I started thinking of FAST - maybe as fast as the ground effect craft? Even faster!?! 100 KmPH? 130? Not a sailboat! To make a really high speed craft, a longer and thinner profile: still flat bottoms, still light weight... like a pair of water skis! To whit, two flat bottoms around 20 feet long and maybe just 8 inches wide. Instead of flying just over the water, it would slide across the surface since it was going too fast to sink in.
   But, to give the craft high strength for high speeds, how about a "tunnel hull" form, a single unit rather than a two-piece "catamaran"? The parts in the water while planing can be just the same. I would make it eight feet wide maximum (so it could be trailered without restrictions) or perhaps a bit less. My construction idea has long been "foam sandwich": PP cloth epoxied over styrene insulation foam - strong and lightweight. (Polypropylene cloth (AKA, eg, "landscaping fabric") is lighter, stronger and nicer to work with than fiberglass.) But maybe some wood to face the bottoms of the "skis" and take impact of gravel beaches or whatever. The front edges would however dome to a point to cut through waves when rough.
   Then we get to the motor and propeller. How does one prevent cavitation at high speeds? Okay then, how about ditch the outboard and have a fan in the air, like the ground effect craft? Now we're riding ON the water, and nothing is IN it.
   Now, what about rough water? How to avoid thin hulls diving in when the the boat aims down after cresting a big wave? And how to avoid having the bow rise up and the boat flip over like those high speed racing boats are prone to doing? My ground effect craft had the ducted fans mounted near the front on a canard, and the canard could pivot up or down. This gave both an airfoil and thrust aim that could keep the craft more or less level as it passed over top of the waves and the consequent varying ground-effect lift. How about making this similar: move the propeller from the rear to the front and have it aimable up and down? It could even have the canard too, and perhaps actually lift the bows out of the water over dips to keep it level. (Sensors and computerized pitch control could make it all very simple to operate.)
   In fact, one could have the fan aimable in all directions to do the steering, too. Again, no rudder - nothing at all - sticking down into the water to cause drag.

   I had thought of solar panels over the front sections, perhaps enclosing a forward cabin of sorts. That seemed cool, but now a fan at the front would get in the way and cast shadows. And doesn't having a cabin front start to lose the "ultralight" concept? Maybe have to go with "fairly lightweight"? Well, the motor and batteries plus even the lightest craft construction would probably make it too heavy already. "Trailerable" rather than something two people can lift and set in the water. Oh well! (At this point, it should carry a small emergency outboard at the rear: meaning, it should have a transom to mount an outboard on.)

   This evolved a bit further... Such a boat apparently isn't for going fishing, it's for transportation. If it was going to go at highway speeds, shouldn't it have an entirely closed in cabin like a car or airplane? Who would want to ride in an open "convertible" in cold weather or with ocean spray misting all around? And with a larger enclosed cabin, there should be room for solar panels on the roof. Maybe even a peaked roof with a panel or two on each side? That would provide more height for getting across the center section with its high floor.
   Then there's motive power. It seems to me that water drag would be very minimal at higher speeds. Again it would be On the water, not In it. And it doesn't need to actually take off like the ground effect craft. In outboard applications one horsepower of electric outboard is said to equal four of gas. A ten horsepower (7500 watt) electric motor running a ducted fan at 4000 RPM might be suitable. (I still have the Curtis AC34 or AC35 from the Swift. That should be about right. Being 96 volts it would need a lot of 300 AH LiFePO3 cells, but then, it should run for towards four hours on them. Easily enough to go to the mainland and back. Wow! That could beat any other sort of transport for rugged coastlines or disconnected archipelagos except an airplane, with ultra-low energy use!)

   Since I wasn't planning to have my ground effect craft go faster than 100 KmPH anyway, this new plan, especially as a "hybrid" sort of craft with a pivoting front propeller and canard with lift to hold the front end up instead of bouncing in and out of the waves, seems superior in almost every way. The ride doubtless won't be quite as smooth as actually flying, but it should be much better than most any other boat of this size range in rough water.

   This would of course be a major, time consuming project. But much more sure in construction than the ground effect craft and much more sure of giving a good result. And I'm pretty sure it would be safer.

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   A further (if probably worthless) thot: always more than one way to do something... One could do the snowmobile trick and have a "treadmill track" with ridges as a sort of extended "paddle wheel". This works amazingly well for snowmobiles, keeping them on top of the water even without them having bouyancy. A track at the front might pull the craft up over the waves as it hits them.
   I can't think this would be as effective as the air propeller and canard.

[2025 02 05] Looked up "Air Boats" or "Fan Boats". These are the ones one might see in the Everglade swamps with propellers at the rear and steering vanes behind them. Apparently some have also been made to travel over 100 MPH. So my planned speed of 80 MPH isn't even very remarkable. And they have generally just got flat bottoms, too. That's great in flat calm water. "Water skis" should be good in rough water, and with the front fan and a canard for attitude control, even in quite rough water.