Oh Lordy (Doug)

http://www.monofoil.com/boat/index.php

 

you said it brother

 

Didn't I see something like that walking around on "Starship Troopers"?

Steve

 

I smell a lawsuit ...

 

Interesting but scary and very ugly. That’s a crossover between an airplane and a boat. I don’t see how that thing is going to sail in normal sea conditions (waves) unless it is huge and that will make it even scarier

 

Interesting to follow further developments and find out if it doesn't brake into pieces or go flying around like an unwired kite if eventually the foil happens to come out of the water. Because of its look it should be called the 'spider monofoil' or the like.

 

The chap leading this was an areonautical engineer and has had scale models working really well. I guess developing the concept to work at full size is the real challenge. The physics is good, but there must be one heck of a load in the foil. I think there is real potential in this idea and I wish the team all the very best luck.

 

Which part is in the water???

Steve

 

I think that will alternate.

 

http://www.monofoil.com/boat/design.php explains that bit.,...
It's more airplane than boat, if you ask me... essentially an asymmetrical glider or sailplane that's held on course by a small hydrofoil. Weird, to say the least. I'm curious to see if it works, and if it does, how many times it can crash before it falls apart.

 

As I said...the part touching the water will alternate..very quickly and for a very short period of time.

I love how a group of nerd engineers think they can just show up and more than double the sailing speed record in their first attempt. I wonder if any of these guys have ever gone that fast in their car. Boy are they in for some surprises...or what!

 

I don't think it can tack while moving, though. To tack it appears to come to a dead halt, spin the whole wing-strut-foil assembly 180 degrees, and continue on the opposite tack. So operating within its design parameters it shouldn't be subject to quite that sudden a movement. But give it some gusts, or some turbulent air.... now that'll get really bumpy really quick.

 

Look in the records section of their website. Here is what they plan to go for:

1. 500 metres outright speed
2. One nautical mile outright speed (the shortest, legitimate ocean record)
3. Round the Isle of Wight (50 nautical miles)
4. Cross-Channel from Cowes to Dinard (138 nautical miles)
5. Fastnet Course (605 nautical miles)
6. Round Ireland non-stop (708 nautical miles)
7. 24-hour distance record

THE FASTNET!!!! Have any of these blokes done the fastnet, on say a standard monohull? Maybe they have, I don't know, but I am curious.

 

Questions questions questions

Why not ask the designer?

I believe his name is Jon Howes and he monitors these groups ... he posted to the Builder's Open thread to correct my mis-assumption about her tacking abilities ...

Jon ... do you care to step in here?

Trevor Paetkau

 

I am dubious about the idea that a small model is proof of a concept.

Even the "boring old 12 metres" found out decades ago that scale effects can play havoc with model tests - remember Mariner?

Has anyone seen videos of the Pacific Islander model yachts which are modelled after trading schooners combined with proas? I think they are solid wood, gaff schooners, with long flexible crossbeams. They go like all hell let loose, accordng to the films I've seen. So if model testing always provided a foolproof way of working out what would work in the real world, we'd have planing-hull solid-wood gaff schooner rigged 70 footers.

Another example would be the model "skimmers" that gold medallist and skiff champ Peter Mander used to make from (I think) metal pie plates. Apparently they'd go like stink downwind, too. But for some strange reason, the boat the Manders designed and won two world 18 Foot Skiff titles in was shaped....well, like a boat.

Dr Bernard Smith spent decades messing about with radical models that "worked", but never actually managed to translate that to an effective full-scale sailing craft that could do those minor things like tack. Frank Bethwaite, inspired by Smith, spent decades trying to get his concepts to work full-scale, and then abandoned them having realised that those concepts do not work in real-life winds.

The windsurfer sailmakers have followed a similar path; the search for theoretical aerodynamic efficiency peaked around '84 (I think) with the Haywood wing. Since then, getting the sail to handle gusts and other fluctuations seems to have been a higher priority (although I confess I haven't asked any of the top sailmakers about speed sails for a long long time)

It's interesting that a yacht designer of some fairly good 18 Foot Skiffs confessed that really, super-fast boats were not the area someone from his background should have been working in. The only people who really knew what was going on at high speed were the practical sailors who had been there, like Bethwaite, Brown, Farr, Bowler and Murray, or Cunningham. Theory and book learning, he implied, just didn't cut it at 30 knots under sail.

And who created the style of sailing craft that holds the world record, the windsurfer? A real-life rocket scientist (well, he created the specs for rocket planes), but who seems to have a very different approach. Jim Drake didn't mess with models, but went out and tried things real-life. And while he used to be a NACA aero and therefore must have the theoretical knowledge, he says that his explanation of the way that windsurfers work “is a combination of theory and intuition. My answers about why certain features are the way they are should be considered as my opinions, while based on theory, more than proven technical fact.”

While theory is a wonderful thing, it's interesting to see so many of the top names seem to see it as more of a guide to how things may work in a very fluid and ever-changing pair of mediums. Sometimes other people seem to see everything as a more "straight line" process. The interesting thing is that the vast majority of progress in high-speed sailing seems to come from the former group.

Of course, I may well be talking rubbish.

On the other hand, would a simpler lifting surface/inclined foil work? Think kitesurfing kite; shorter lines; sailor suspended mid-air; then more lines to an inclined foil in the water for lateral resistance. Of course, I can't see many reasons why it would be quicker than a normal kite, and there's no way I'd do it myself!