Oh Lordy (Doug)

[bobothehobo]

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

[water addict]

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

you said it brother

[lewisboats]

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

Steve

[RHough]

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

I smell a lawsuit ...

[Vega]

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

Steve

:p :p
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 :D

[Guillermo]

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.

[PI Design]

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.

[lewisboats]

Which part is in the water???

Steve

[DGreenwood]

Which part is in the water???

Steve

I think that will alternate.

[marshmat]

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.

[DGreenwood]

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!

[marshmat]

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.

[bobothehobo]

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.

[tmark]

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

[CT 249]

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!

[Doug Lord]

Ct, many people in the design and development world have used models to prove their new technology would work and then gone on to prove it full size. Among them are Bill Burns of CBTF, Yves Parlier "Mediatis Region Aquitaine(planing cat), Greg Ketterman- (numerous foilers), Dr. Sam Bradfield at least one foiler that I know about tested as an rc model and, I'm sure many others.
Foilers test really well at small scale for a lot of factors that bear on the performance of the finished boat including altitude control systems, foil placement/CG, tacking abilty and more.
--------------
I wish Jon and the Monofoil guys the best of luck and admire the guts, courage and foresight it takes to make a project like that work.
The guys that first foiled the Moth bi-foil monofoiler did something that at least one "expert" in the field said wouldn't work.
Jon: good luck and never,ever give up!

[CT 249]

Doug, scale models can be very helpful. However, I was just saying that the fact that a model works does not mean that a full-size boat works. Look at Bernard Smith's work; even the webpages for his book readily admit that ideas that worked in his models did not work in the full-size craft.

Frank Bethwaite went to Smith and watched his videos and spent 20 years and 19 full-size boats trying to get his concepts to work. He didn't succeed. He found that the Smith concept needed too much sail to lift off onto the foils and notes that "Bernard's tiny balsa models had been so light (the cube/square law in reverse) that he had not been faced with this problem".

So all I'm saying is that success in model form does not PROVE success in full size form will follow. Hell, Farr, Bowler, Jackson, Murray and many other designers have found out you can't scale a 12 foot dinghy up to 14 feet or 18 feet long. Spencer found you can't use a 26 footer as an infallible test for a 62 footer. A scaled up butterfly could neither respirate or fly. Scaling effects matter, we all know that. You can't even scale up a fast speed board to make a fast big windsurfer.

That's not saying that models aren't great tools for design, I'm just pointing out that the evidence is that they are nothing like infallible.

[Thin water]

Check out the scale model movie on their site, It really moves out. Boats have looked very similar for hundreds of years, even hydroplanes have not gained a lot of speed in thirty years. It may be time for a change. This looks like it is good for nothing but it's intended purpose, setting the world record. If it doesn't break (Looks likely) and the wing can be kept from touching the water (could prove fatal) they just might pull it off on a good day. If the foil exits the water I think it will pile up in a heap after cartwheeling. To be a success with this design they can't just break the record, they must smash it by a good margin. I wish them good luck.

JIM

[DGreenwood]

If they were making claims of a 5% increase in sailing speeds I would have a lot more respect.
I have a question---If this thing will work on water(the wing I mean), wouldn't it work better on ice? What do record breaking ice boats look like?
C'mon this isn't the 30s! You just don't show up with a design out of Popular Mechanics and increase established records of the sort they are after by 100%.
Long distance sailing records see big leaps sometimes because of weather system luck or because a small increase in speed will allow better facilitaion of weather patterns.
The sailing speed record over a short course has inched up over the years 1 knot here and there. Now we are going to see it increase by 45 or 50 knts.
Wow these guys are impressive.

[Guillermo]

... that scale effects can play havoc with model tests
yes, absolutely.

Why don't we open a poll here and vote about if it's going to break into pieces or not? We should even risk some money on the bet! ;)

[PI Design]

I totally agree CT, models have their place but are not the be-all and end-all. Its funny you should propose a kite, beceause this design evolved from the kite and hapa combo that has been around for a while. I presume they switched to a solid set up to get lower drag, but, of course, structural strength is now a far greater problem. I wouldn't say thay that it is an aeroplane any more than a kite surfer or foiling Moth is. Having said that, I can't see it having any great effect on traditional yacht and dinghy sailing - it really is a stand alone project.

[Jon Howes]

A quick post as I am running late for a meeting:

Purpose of models;

The models are validation tools for an analytical model. The analytical model is used to design the next iteration. The full scale boat is not a scaled up model.

Scaling laws;

Bread and butter to an aero engineer. See above.

Me (the "nerd engineer");

Sailing since I was five, now I'm 47, work it out. Experience: The inevitable Oppy followed by British Moths. Various other dinghy and offshore experience, current boat, 5 tonnes of 1936 rotting rainforest with a collossal sailplan. Aero engineer since 1980 or thereabouts, until I left to start my own business I spent 5 years in transonic wind tunnel testing, a couple of years working on robot helicopters and weapons concepts, then 16 years with the UK Civil Aviation Authority. I was the head of the EASA Structures certification team for the Airbus A380. Concord involvment was limited to working out why the tank failed under internal pressure after being hit externally in the wake of the Gonesse crash. Been flying hang gliders since 1984, Pilots licence since 1995. Flown sailplanes as well.

Monofoil development and the "How dare these people think that they can turn up and go faster than my favourite speedsailor" argument;

Under development since 1995. Six variants of models of different sizes, purposes etc. (video of three of them on the website). Public presentation in 1998 at the Speedweek AYRS meeting. One overseas gentleman whacked in a patent application on a startlingly similar configuration one month after the meeting, his application even included some of the mistakes that I was making at the time, fortunately, these errors, if propagated to actual testing mean that his boat, as patented, will never work... Could these be related? The hearing will tell.

Answer to the "Have these people ever been that fast before";

Fastest aircraft flown to date, about 200kts, fastest boat, 70mph (powerboat, what a pointless activity...)

As for the "how dare they" crowd, how do they think progress is made? By doing nothing? By being a technological wimp?

100 knot claims;

We haven't, we have designed for loads arising at 100 knots. Would we have been more sensible to design for loads at 50 knots and enjoyed the sound of crunching carbon at 60? The boat appears to have the capability to go to the design speed in a manageable wind strength so why stress it for anything less? Would the sensitive souls who get all jittery at people having a go feel better if we aimed for 51 knots? If so pour yourself a nice mug of cocoa, go to bed early and stop looking at scary web sites;)

Loads;

At the design point the wing is pulling 2.5 tonnes, the foil about 2 tonnes. By the way, the wing weighs in at 100 kg give or take a coat of paint.

Assymetric, Stopping to tack;

No, in theory it could fly through a tack but I am not inclined to try. Same performance on both tacks.

Stability;

Fully stable in six degrees of freedom. Models are free sailing with no radio intervention. If it totally leaves the water re-entry is stable and controlled and desiged to be so.

Rough water behaviour;

One model has run in .4 m waves, this model was only 1.2m long. Full scale is designed and stressed for a peak to trough wave height of 1.25m at full design speed, more can be handled if speed is reduced. Full speed is therefore sheltered water only, as loads reduce with speed squared a reduction to 70kts would give an additional safety margin of approximately 2.

Given the title of this thread, I notice that Doug Lord often seems to upset people, largely by being different. At least he has a go, sure, some of his designs and concepts will not behave as well as he would like, that is the cost of trying something new. If rocks are thrown at hard work the sailing world at large should be very grateful that the innovators have the determination to keep going otherwise we can all forget (for example) living in houses and get back up those trees!

More later after I have enjoyed the brickbats flying out of the collective armchairs.

Regards,

Jon.

[Doug Lord]

If they were making claims of a 5% increase in sailing speeds I would have a lot more respect.

C'mon this isn't the 30s! You just don't show up with a design out of Popular Mechanics and increase established records of the sort they are after by 100%.
The sailing speed record over a short course has inched up over the years 1 knot here and there. Now we are going to see it increase by 45 or 50 knts.
Wow these guys are impressive.

----------------------------
In the real world of the Moth class foiler speeds have increased from 23 knots last year to 33.4 knots this year, an increase of 45.2% . So large percentage increases are most definitely possible.

[CT 249]

Thanks for the reply, Jon.

Maybe there's a simple reason for people asking about the level of experience of the group. There are no bios on your site. Googling a couple of your top team members brings little information about issues which some people may think may have some relevance, such as the level of experience in high-speed sailing.

I'm not in any way saying that there is any lack in the team's ability and experience in these areas; I am merely pointing out the available information doesn't give any reason to assume it is there. Yes, we could take it as read, but perhaps being so credulous is as bad as being so cynical.

I hadn't realised the direct link between your boat and Smith's work. Was he less aware of the scaling laws? Where they less developed a few years ago and was that responsible for the failure of his (and Frank Bethwaite's) full-scale boats to live up to the performance of his models? I know FDB lacks your formal qualifications but he does have significant experience in sailboat design and many years of full-scale work with boats inspired by Smith. May I ask where you think he went wrong in his attempt to apply these ideas?

Re "100 knot claims". With respect, to many readers website headings such as "Breaking 100 Knots" does seem a lot like making 100 knots claims, which are supported by headings suggesting 50 knots is a "cruise".

[Jon Howes]

Hi CT,

There was no direct link between this work and the Bernard Smith boats. I only "discovered" Bernard Smith after I had been sailing models of this concept form a couple of years. The origins were in consideration of kite boats and what limits their performance, these issues being mainly drag, stability and control (not much left!). The Bernard Smith work still failed to track down some fundamental aspects of stability, briefly: Position of aerodynamic centre about three axes, multiple points of lateral resistance (what happens when one of them lets go?), zero heeling moment without any attempt to develop any heeling stiffness (equilibrium without stability).

Replacing the string with a rigid streamline foil does much to facilitate the oft-discussed kite+hapa with pilot on the string concept but does not stabilise anything and stability is only a very distant cousin of equilibrium. Most of the work was to ensure that both static and dynamic stability was present during acceleration, at speed when surface running, at speed flying, flying with the foil entering and leaving the water.

Most designs that I reviewed in the early stages had been the result of the expenditure of much effort simply chasing equilibrium of forces, this is a largely pointless excercise as equilibrium will arrive naturally if stability about all three axes is is provided, for example, I have not found a single example of a high speed sailing craft that has the aerodynamic centre (neutral point) longitudinally behind the CG, not doing this leads to a flip over if the boat ever leaves the water, leaving the water is a certainty at some point if high speeds are contemplated.

Control may be defined as intentional perturbations to the stable state. This is what ultimately allowed the test models to fly without human input.

Jon.

[DGreenwood]

Doug:
You can always pull up some examples of an underdeveloped class that made a recent big leap. The moth is a poor example. That class had not seen the kind of engineering effort that world speed records had seen. It was guys mostly building them in their garages. And keep in mind he is going up against the ORMAS and some pretty smart guys that have been working at foils and the speed record for a very long time.

"100 knot claims:

We haven't, we have designed for laods arising at 100 knots. Would we have been more sensible to design for loads at 50 knots and enjoyed the sound of crunching carbon at 60?"

Pardon Me? Here is the claim from page one of your web site:

Breaking 100 Knots
Monofoil has been designed to reach an outright top speed in excess of 100 knots. While this may seem wildly ambitious in conventional sailing terms, it is a relatively modest speed in an aeronautical environment.

You go on to say that 50 to 70 knots is a "cruising speed" for this boat. And top speed are only dependant on the nerve and durability of the pilot.
Granted you do not outright claim in that statement to be abe to reach 100 knots but everyone would assume you mean to say that.
Your audience is very small. Some of them very experienced and some of them have heard big claims before.
I am aware that you probably need to raise money and dazzling the sponsors is what it is about. On the other hand don't you think that a responsible sponsor is going to investigate the feasability of your claims?

Just curious...have you ever sailed in excess of 30 knots?

Have you spent any time talking to (for example) the C-class cat guys or how about any of the folks that work on foil borne tris and cats? What is their response to hitting the modest speed of say 70 knots?

And I am still curious about the ice sailing thing?

Another question is:
Doesn't the recent ORMA carnage i.e. the Route du Rhum, make you wonder how these fellas could be so stupid as to not be sailing on foils with solid wings. Jeez with average speeds under 30 knts they are barely moving.

All you need is a moderate weather condition and you can show them how it is done around Fastnet Rock!

[Jon Howes]

"don't you think that a responsible sponsor is going to investigate the feasability of your claims?"

I sincerely hope so and I will demonstrate the full basis for them to any serious potential sponsor but not here.

"Just curious...have you ever sailed in excess of 30 knots?"

No, and I have never flown in excess of Mach 2 although I have designed devices that have gone on to do precisely this. Your point is?

"Have you spent any time talking to (for example) the C-class cat guys or how about any of the folks that work on foil borne tris and cats? What is their response to hitting the modest speed of say 70 knots?"

Of course I have, swapped emails with Greg Ketterman (he liked it), know the sailrocket crowd, got bored at Speedweek. What have these people got to say about CFD design of foils and three axis stability? Very little. Your point again?

"And I am still curious about the ice sailing thing?"

Monofoil is not, and never could be, an ice boat for some fairly obvious reasons, not least that the foil spends some time creating downforce even when the average force vector has an upwards component. Without this ability to create downforce ice could never generate sufficient sideforce to react the rig at design speed.

"Another question is:
Doesn't the recent ORMA carnage i.e. the Route du Rhum, make you wonder how these fellas could be so stupid as to not be sailing on foils with solid wings. Jeez with average speeds under 30 knts they are barely moving.

All you need is a moderate weather condition and you can show them how it is done around Fastnet Rock!"

Grow up or get back in your cave. This is why I would rather solve engineering problems than waste time on forums.

Jon.

[water addict]

Jon,
In what true wind speed do you get boat speeds of say 30, 40, 50, 60 knots?

[RHough]

Grow up or get back in your cave. This is why I would rather solve engineering problems than waste time on forums.

Jon.

That's an interesting comment from someone that thinks they deserve respect.

[DGreenwood]

This is why I would rather solve engineering problems than waste time on forums.

I don't know about that--- you seem to be pretty skilled at muddying the water and dodging simple questions. And I am sorry to be wasting your time.

We will see who is in the cave when you put this thing on the water. And if I am wrong I will personally get on one of those planes that you have partially designed and come to congratulate you.

You are the one making extravagant claims. You are the one that has to explain them.
Getting testy over some difficult questions by experienced sailors and boat builders does tell me something about your where your ego is.

By the way I can see your point with testing on ice. I hadn't thought of the lack of side resistance.

[Jon Howes]

"Another question is:
Doesn't the recent ORMA carnage i.e. the Route du Rhum, make you wonder how these fellas could be so stupid as to not be sailing on foils with solid wings. Jeez with average speeds under 30 knts they are barely moving.

All you need is a moderate weather condition and you can show them how it is done around Fastnet Rock!"

This is not a question, it is a plain and simple attempt to be obnoxious. As for Mr Greenwoods other comments along the lines of "have you ever..." I have done plenty, it's called experience, some good, some bad, some pointless , much still to come. For example, two American bicycle builders engaged brain, built, and then flew an aircraft in 1903, they had never even been up in a balloon. Does this mean it did not happen?

"That's an interesting comment from someone that thinks they deserve respect"

I could not care less about respect, developing this thing has been (so far) eleven years of damned hard work. Armchair experts or "Experienced Sailors and Boatbuilders" as you put it, who insist on implying that we just dropped this thing on the water after a good night in the pub do not deserve any respect whatsoever. I am happy to answer questions, I will not field belittling rubbish unless you want a stroppy response which you got.

As for the only real question to appear since the last blast: Speeds at which things happen:

Full flight is expected at 47kts. Below this speed some weight is carried by the hull and I do not have reliable drag data other than some basic CFD (unreliable with spray) and some flying boat hull data so although the wind speed to boat speed ratio is non-linear below this speed and is poorer at lower speeds the exact function will have to wait for some real data. As Bob Downhill of Weymouth Speedweek/Icarus fame etc said, the first ten knots can be the hardest! Personally I think that the next few knots can be pretty interesting as well.

The clean wind speed ratio for marginal flight is 3.44 times wind speed, ie, full unstick needs a 13.7 knot wind at the mean rig height. As speed is gained the rig is vectored forwards (bias tab on the rig) to reduce the vertical lift component and again, things get a bit non-linear although this ratio remains roughly constant until things start to break. All this is estimation validated by models so we shall see.

Jon.

[DGreenwood]

This is not a question, it is a plain and simple attempt to be obnoxious. As for Mr Greenwoods other comments along the lines of "have you ever..." I have done plenty, it's called experience, some good, some bad, some pointless , much still to come.

It is fact part of a very big question. A question that you so far have refused to answer. That is: Doesn't it worry you in an age where many great minds equipped with so much information about a topic they have been toiling over for so many years are so easy to best, and by such a large margin?
I am not being obnixious, I would just like my question answered without a string of aeronautical jargon.
You have designed an impressive looking machine and I am sure you"re a talented engineer. I don't doubt any of that. But, to use your method of analogy, you are not telling me you have found a way to fly for a few hundred feet, you built an F16 in your barn.


I am not equipped with the education in fluid dynamics to refute your claims that these speeds are possible. None the less you have to see that your claims do come across as arrogant.
Some of my experience has been in watching already scarce sponsorship, squandered by less than realistic programs. I cannot control those outcomes completely, but I can damn sure ask some questions about what you are up to...and, as you have shown, you can damn sure not answer them.

[Kaa]

It is fact part of a very big question. A question that you so far have refused to answer. That is: Doesn't it worry you in an age where many great minds equipped with so much information about a topic they have been toiling over for so many years are so easy to best, and by such a large margin?

LOL. Very much reminds me of:

Everything that can be invented has been invented.
-- Charles H. Duell, Commissioner, U.S. patent office, 1899

Kaa

P.S. Yeah, I know, the quote is an urban legend.

[water addict]

[I]"Another question is:
...stuff deleted...

The clean wind speed ratio for marginal flight is 3.44 times wind speed, ie, full unstick needs a 13.7 knot wind at the mean rig height. As speed is gained the rig is vectored forwards (bias tab on the rig) to reduce the vertical lift component and again, things get a bit non-linear although this ratio remains roughly constant until things start to break. All this is estimation validated by models so we shall see.

Jon.

See if I'm getting this right, so at 13.7 knot wind speed the craft weight is balanced purely by aero forces and the boat speed falls along the line of 3.44 * wind speed? So at about 14 knots wind speed you expect in the vicinity of 48 knots boat speed? And 18 knots gives over 60 knots boat speed? That is impressive if I read this right.

Another question- if it's estimation validated by models, how could you get 3 significant figures of accuracy without spending about a million bucks on your model? (just being a bit of a pain here I know, tongue in cheek)

[Jon Howes]

Kaa:

Some sense! I can only agree with you wholeheartedly.

Greenwood:

"A question that you so far have refused to answer"

Sorry, what question have I refused to answer?? If you ask me a sane question I will attempt to answer it. This is many years work, I am hardly going to be able to give you everything in a couple of forum responses. Let me see:
Foil design, a right little bastard of a problem

Six degree of freedom stability across the entire speed range from rest to full chat, Hardly trivial

Free feathering rig stability, This one took me four iterations and near total despair before I cracked it

Single point water reaction, nice in principle but non-trivial in solution

Model testing, consider the wind gradient, for a model this is extreme, can you visualise the problem of doubling of wind speed for a couple of inches gain in ride height?

Model testing again, how to record what is happening to a model with sufficient fidelity to mean anything when fed back into a math model.

"Doesn't it worry you in an age where many great minds equipped with so much information about a topic they have been toiling over for so many years are so easy to best, and by such a large margin?"

Who in hell said that this has been easy?????? What do you not understand about "damned hard work"???? It might fail, your approach will (has?) failed, how fast have you or anything that you have done gone? I may not ultimately be proved correct but at least I have not simply sat on my backside and criticised other's efforts. Perhaps it is time to stop this before anyone is embarrassed any further. Give credit for trying or put up and shut up.

If the question is "why has it not been done by someone else" (which is what it looks like to me unless you explain otherwise) then this is the argument of ********s who do not understand invention. It needs no further comment, get medical help.

Jon,

Happy to answer real technical questions from anyone, even Mr Greenwood!

PS, To Water addict, Yes, you are broadly right about the wind speed ratio but it all goes non linear past lift off speed. The numbers would be pretty poor for a current ice boat but are what pops out of analysis for this wet boat.

The three sig fig, you are completely correct, of course we cannot expect anything like this level of accuracy but you know what math models are like! I could have given you 1 sig fig or 10 sig figs, take your pick.

[gggGuest]

The moth is a poor example. That class had not seen the kind of engineering effort that world speed records had seen. It was guys mostly building them in their garages.

Do you know *anything* about Moth development? Or for that matter the facilities and finance available to Lindsay Cunningham with Yellow Pages Endeavour?

[DGreenwood]

Urban legend or not, I certainly do not subscribe to that sort of thinking. I will (and have) donated time and some of my scarce money to those who dream of achieving a new level of excellence. However I have tired of the hotshot that strolls in and tells 'em how it's done.. They burn a pile of money and find out that they could have contributed something real had they allied themselves with people who have already been down the road with this stuff.

Now to be clear, I am not accusing Mr Howes of any such behaviour. Genius falls out of the sky sometimes. Sometimes these things are just simple ideas that completely change the world. Maybe hidden in all talk about fluid dynamics and different effecting forces is a secret that will revolutinize sailing.
I want to know what that is?
Can he build a radically stronger structure? Can he radically reduce the loads on that structure, is there something that we have all missed? To date many attempts by skilled engineers has resulted in much shredded carbon and hexcel. Some have upped the anti by a couple of knots.

I just don't think that any realistic campaign to reach the goal he is after, would feel so superior as to brush off questions about such extravagant claims, as the rantings of a fool. I don't think he believes it himself.

Am I skeptical...Yup...am I cynical...a little. After you have worked your ass off and spent your money on few hucksters and scoundrels, you learn to ask hard questions. Believe me, they all sounded so sure of themselves.

[Jon Howes]

Mr Greenwood,

I am about to give up on this:

"I just don't think that any realistic campaign to reach the goal he is after, would feel so superior as to brush off questions about such extravagant claims"

ASK ME A REAL TECHNICAL QUESTION AND I WILL ATTEMPT TO ANSWER IT!!!!!

GET IT???

Jon.

[DGreenwood]

Here is some I have already asked!
Can you build a radically stronger structure? Can you radically reduce the loads on that structure, is there something that we have all missed? To date many attempts by skilled engineers has resulted in much shredded carbon and hexcel.
Why won't it happen to you?

[patrik111]

Let the man speak without needless stupid questions.

I for one are more than happy to realise that invention rarely comes from people sitting on their ass. Let failing be an option!

Leonardo da Vinci said once something along the line:

Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.

And yes, I realise qouting him makes me one of the persons using my memory, but also I do happen to agree.

But what I was really aiming to say is this:
You do ill if you praise, but worse if you censure, what you do not understand.

I would like to hear more from this and intend to watch this space for further updates. The more the better!

//Patrik

[marshmat]

Well, I enjoy a good argument now and then... but I'm going to interject with some of my own thoughts on the thing now that I've had a chance to read through more stuff about it.
Do I think it could work? Yes. Getting the full scale unit to run in a stable condition is going to be tricky, to say the least, but the physics behind the thing appear sound as far as I can tell.
Do I think it will crash out? Yes. Many times. Nobody has ever tried something like this before and it will take a lot of time and a lot of failed runs before it flies. Then again, how many gliders did the Wrights smash up before they finally got their airplane to work? How many Airfish went end-over-end before the Flarecraft flew? How many Moth foils snapped off, or snagged on debris, or just plain disintegrated, before they caught on? It'll take time and patience if such a radical idea is to be brought to life. (On that note, I would hope the Monofoil prototype will be overbuilt enough to take a few nose-dives in testing!)
Do I think that Howes and Greenwood are being productive in their arguing? No. In fact, that exchange reminds me of the schoolyard taunting of a grade 5 class. DG, you're skeptical, and with good reason given your background. JH, you're proud of what you've done and fiercely protective of your pet project. Nothing wrong with either position, but be adults and discuss it rationally. We're better than our politicians, right?

[Doug Lord]

I don't think you can lump Jon Howes and DGreenwood together in the same category by a long shot. Mr. Greenwood started out with out-right antagonism, bordering on contempt, questioning the unmitigated gall of Mr. Howes in even suggesting that such a thing could be done given the fact that nobody else had done it. Huh? Approaching a discussion like that with a man that has spent years and considerable effort solving problems has got to be one of the most annoying things I have witnessed on a forum-since the last time it happened to me! If you can't be considerate of the effort,dedication and foresight represented by Mr. Howes work and ask a question in a respectful manner DON'T EVEN BOTHER!!!
Mr. Greenwood,when you a approach a subject like this in an aggressve, uninformed(what did you say about Moths??!!),and disrespectful way you can't possibly expect someone of the caliber of Jon Howes to cater to a discussion with you-you're way off base.

[Vega]

Yes, I agree with Marshmat. Probably that thing is going to break a lot of records, if enough research and money are spent on it. As I have said I believe that for sailing in the open sea, that thing (I would not call it a boat) would have to be big and hugely expensive.

It would be very interesting, but with the movement of the waves disturbing the flight of the wing, and at that speed, that thing would have to be driven like a race engine.

I doubt that an autopilot would be good enough. In a sailboat, autopilots sometimes are not good enough, but it is not a big deal. With that animal, the first small error would make it break into small pieces.

I can not see the use of the beast, except that it would be fun (and risky) to sail it, but the same thing was said regarding the first airplanes, so who knows?;)

[SamSam]

I saw something on the tube last night about the stealth bomber flying wing and they said it couldn't be flown without computers doing a bunch of the work. Will this thing be able to be used without computer help? Will it take more than 1 person to pilot it? What will the operator(s) actually have to do, besides steer (and keep from screaming)? Sam

[DGreenwood]

Marshmat
The physics seem sound to me too. That is, within my limited understandeing of this stuff. And I have no problem believing that they will have a chance at breaking the mile speed record. Of course with the prerequisite crashing and breakages you mention. I never said I don't believe that. Hell I would support him even if I thought his chances were slim to none.
What I object to is, the outrageous statements that they will approach double the existing record and that they will break ocean racing records by huge margins without some explaination of how it will stay together and how come their wing is so superior.
Without some better explanation of what leads him to believe these claims,all this starts to sound like...well like a snake oil salesman. Maybe you need to make claims like that to get sponsorship these days. Maybe sensationalism is a sales tool? Maybe that is what I am missing.


Yes I have taunted him, but I would disagree about the schoolyard thing.
I just want to know why he thinks he can walk in with no background in high speed sailing and at first crack, completely blow away the work of many talented people and the combined skill of the French builders and millions upon millions of dollars of work in carbon fiber.

And as far as this being productive...maybe you are right, but look at it this way, either I will eat crow---big time--- and learn a valuable lesson or many will learn some things about recognising BS when they see it.

Now I will take Kaas advice and let the man talk. If I haven't totally pissed him off and he left.

[DGreenwood]

Shut Up Doug, Nobody likes you anyway.

[marshmat]

Greenwood, that was not a productive comment.

[DGreenwood]

Your right but it was funny as hell

Sorry Doug

[CT 249]

Thanks again for the reply, Jon.

I apologise for thinking there was a direct link between your work and Smiths; for some reason I tend to read sloppily when I look up things for posts on this particular site. It's a bad habit.

Thanks for the information about the inherent weaknesses in Smith's concepts. The fact that a concept with such problems can result in films of models that seem to be working well is, of course, a reason some people aren't happy to use vids of models or the credentials of designers as definite proof that a concept must work. (This is a general remark, not aimed at you).

Would a smaller Monofoil work, or is its current size necessary? Like others, I'm just thinking of the difficulty of getting the same sort of experience with the edges of handling in a big boat, compared to boards or Moths where you can crash and recover easily. Or the way the American bicycle builders you mentioned started with a glider about 13 feet span, then a 22 footer, then kept expanding.

I can understand (just from uneducated gut feeling) that a smaller Monofoiler may not work as well as the full-size one, and therefore starting small may not have been an option.

DG, the foiler Moth guys are not garage mechanics; they include guys with Doctorates in metallurgy (I think; some engineering science type PhD anyway) and a former F1 car builders. The modern-style rig was pioneered a long while ago by Dr Taffy Bowen, one of the early leaders of radar and radio-astronomy.

Re negative criticism of novel approaches; yeah, it can be a problem for some of us, BUT some of those who push novel approaches are quite happy to criticise (explicitly or inherently) the "status quo".

[Chris Ostlind]

DG, for what it's; worth I agree with your position.

Perhaps you could have come at it in stages and let Howes do his own dance in response, but that's gone now.

Looking at the responses from JH, it would seem that he's a little on the testy side of the diagram right now and it shows in the come backs. His claims are arrogant and if he doesn't know it, he should be told same. I get the marketing aspects of the position, but it is rather more than a little premature and rings of other hyperbole spew we have all heard in the past.

Gut level sailors are known to be plain talkers. Engineers can tend to speak in technical terms supported by folders of data. If there were ever a brew for non-stop haggle, that package sets-up as a real winner.

Howes will probably settle down some, you'll temper yourself a bit and there just might be a nice exchange, eventually. Just keep in mind that you are talking to an engineer and they, sometimes, speak a different language that has its own cycle of nuanced value. That nuance is placed on different regimes than other types of folks place on their communication. It would seem that you are both attempting to describe similar things; just in different ways.

As for the attempt, by one group member, to chastise your effort... well, some guys are just truly smitten by their interpretive dedication to all things technical. Our friend clearly regards JH as some dude with a glowing ring around his head like an old, Renaissance painting of the Christ. He'll do anything to stand close to the glow, as he sees it, and will snap at anyone who is the least bit testy with he who wears the glow. Respect is something that one must continue to earn, it doesn’t just sit there sweet and glowing on ones head. Past deeds should be measured with a degree of respect, but it won’t get one far if one is simply sitting around with the aging expectation of it all.

Maybe it's because I've been in combat and had the base line crap scared out of me too many times, but I just don't genuflect at all for anyone based on Letters or clothing. If they come at me like a regular guy and have the humor and ready smile of friendship, they’ll be met with same and personal discovery is ours to behold. It is possible to respect a person for their demonstrated human qualities rather than an assemblage of artifice and technical things. There's no need to scuttle about as if the chosen one were nearby and we just might be sent off to the dark side.

Stay off your knees, maintain some decorum about your humanity and look the other dude in the eye without smooching their butts.


I like your style, DG. Perhaps a little rough, but honest with intent.

Chris Ostlind

PS: I originally posted before the whole, shut-up, thing, so this is an edited post script to ask that you tone it down.

[DGreenwood]

CT 249
Boy oh boy, do you have me wrong! I have the utmost respect for the Moth guys. In my estimation they are the ultimate in the way things develop in this sport. Interaction and innovation based on going out and gettiing wet. There are engineers and resin jockeys building things in their garage or any high tech shop that will let them in the door. Take a look at the Moth site (At least as of a week ago) there are pics of guys proudly displaying single knot increases on their GPSs That is how it happens. Not many of them have big sponsors and they find ways to go a little faster every day. It is the same thing I love about Open class sailing. This stuff happens with Minis and is now happening with the Class 40s.
If you knew me you'd know, I will drive a long way to help out guys with novel approaches. In fact I have finished building boats on Friday at 5 and driven for four hours to work for free all weekend to help out guys with novel approaches. Many times. My family goes without my company for long periods of time so I help out with those kinds of projects.
You can't even guess how many hours I've worked for free teaching guys how to wire their boat or vacuum bag or fair a foil.

I dont need to be lectured on dissing guys with novel approaches. My family will tell you just the opposite. Guys with novel approches dont have any damn money. But they are humble and driven and have hopes and that is what draws me to help them.

I just spent a month in Europe looking at and working on boats at the Velux 5 Oceans and the Route du Rhum. I have sailed on Formula 40s, Open 60s, class A cats, Orange II and many other out of control machines. I've logged well over 150k nautical miles on big ol' clunky wood schooners and light weight rockets. I love the machines and all the technology...but it is those guys with the crazy ideas and chunk of carbon that they scrounged up somewhere to make a foil to go a little faster that I really have a soft spot for.

That is how the Mini, the Moth, International 14s and many others have driven the innovation in this sport. I want to be there when it happens.
Those ideas eventually end up at Multiplast or VPLP or Finot or Goetz or Farr.

And that my friend is why I will always question anyone who tries to steal their thunder and why I will help anyone who can convince me they have a genuine idea.

Chris
The shutup thing was a joke. And if you look at it that way it was funny. I did sincerely apologize.

[RHough]

I don't think you can lump Jon Howes and Dg Greenwood together in the same category by a long shot. Mr. Greenwood started out with out-right antagonism, bordering on contempt, questioning the unmitigated gall of Mr. Howes in even suggesting that such a thing could be done given the fact that nobody else had done it. Huh? Approaching a discussion like that with a man that has spent years and considerable effort solving problems has got to be one of the most annoying things I have witnessed on a forum-since the last time it happened to me! If you can't be considerate of the effort,dedication and foresight represented by Mr. Howes work and ask a question in a respectful manner DON'T EVEN BOTHER!!!
Mr. Greenwood,when you a approach a subject like this in an aggressve, uninformed(what did you say about Moths??!!),and disrespectful way you can't possibly expect someone of the caliber of Jon Howes to cater to a discussion with you-you're way off base.

We can all recognize hype when we see it. DG has real life experience with high speed sailing, we don't know if you or JH do. Spending considerable effort is absolutely no indication of probability of success. You of all people should know this.

JH was the first to lower the bar with "Grow up or get back in your cave. This is why I would rather solve engineering problems than waste time on forums."

Now you are up on your familiar high horse and make predictable comments about the character of others.

Your style is very close to JH's, it does not do a very good job of convincing anyone about your ideas and does a dandy job of making enemies.

BTW ... Considerable effort ... hows that foiler coming? Full scale or model?

[Jon Howes]

"Can he build a radically stronger structure? Can he radically reduce the loads on that structure, is there something that we have all missed? To date many attempts by skilled engineers has resulted in much shredded carbon and hexcel. Some have upped the anti by a couple of knots."

I can analyse loads and design a structure to suit. If you don't have a handle on the loads you cannot design anything with any certainty. The wing, for example has a peak limit load of 2.5 tonnes, with a 1.5 safety factor this is a design load of 3.75 tonnes. To get these loads (just as with an aircraft) you start with load cases, work out the effect of the various load cases on the bits and design each bit to the worst case. The load case for the wing is smooth water, max speed. The load case for the cross boom for example is foil re-entry after about four seconds out of the water. The load cases could be wrong, right, or over the top, they are my best shot from current state of knowledge. The structure follows from the load analysis.

"Do I think it will crash out? Yes. Many times. Nobody has ever tried something like this before and it will take a lot of time and a lot of failed runs before it flies. Then again, how many gliders did the Wrights smash up before they finally got their airplane to work? How many Airfish went end-over-end before the Flarecraft flew? How many Moth foils snapped off, or snagged on debris, or just plain disintegrated, before they caught on?"

This is a sensible comment, there have been plenty of interesting incidents during model testing and I am sure that they are not over, if it was easy everyone would do it. I have worked the stability of the various elements as hard as I can without full scale testing so the only options are give up or proceed. Most of the structure is, or will be, overbuilt to some degree. The wing is the weakest element but as this looks to be the component that is least likely to be correct first off it is built as a one-off from wood (the rest is composite) so that changes can be made simply and repairs will not need over controlled facilities, it is chunky, the upper spar cap for example is sitka spruce, 75mm wide by 95mmdeep at the root, lower cap is a bit lighter due to the difference in compression and tension strengths of timber.

"It would be very interesting, but with the movement of the waves disturbing the flight of the wing, and at that speed, that thing would have to be driven like a race engine.

I doubt that an autopilot would be good enough. In a sailboat, autopilots sometimes are not good enough, but it is not a big deal. With that animal, the first small error would make it break into small pieces."

Disturbance to the free feathering wing was an issue in need of solution. The key elements are the degrees of freedom of the wing, its static stability margin (a bit like the CG range of an aircraft but for CG read pivot point), the mass balance and the reative position of CG and rig pivot. The wing is free about its pitch and yaw axes but stiff about its roll axis, ie, a two degree of freedom pivot, this means that if the boat is disturbed by (for example) a lateral gust to weather the rig will feather towards the hull, ie, into wind, this causes the pivot to reduce rig roll, reduces the drive component (de-powering) and slightly increases the lift component. The resulting slight lift of the hull from its steady state causes a slight roll to weather, this reduces lift on the hull horizontal tail which causes a slight nose up pitch, which due to the previously mentioned roll to weather, has a slight upwind yaw component (also de-powering), the increase in wind during the gust is thus met with a corresponding de-powering of the boat. This is a handful to describe in words but coupled behaviour like this can also be found in any other vehicle dynamic stability problem. The worst thing that generally can happen is a wave actually hitting the wingtip, this gives a sudden purturbation to the wing which can result in some nasty transients, stable and damped but it can deliver a rough ride.

"Will this thing be able to be used without computer help?"

Yes, it is stable. The aircraft that use computers are either marginally stable or are unstable, the reasons for building an undstable aircraft are that reduced or negative stability leads to lower trim drag and faster control response (usually in combat). Canard (tail first) aircraft have particularly poor drag characteristics if stable due to the high cruising CL that the canard needs to maintain, however, unstable canards can equal or exceed the efficiency of conventional aircraft. Either computer or aerodynamic servo control of these aircraft is essential, the Rutan Voyager used an aerodynamic servo on the canard elevator for this, most military aircraft (the Eurofighter Typhoon for example) use computers.

"What I object to is, the outrageous statements that they will approach double.... etc etc"

These outrageous statements are design targets based on work to date. Is your philosophy "Aim low, avoid disappointment."?


"I can understand (just from uneducated gut feeling) that a smaller Monofoiler may not work as well as the full-size one, and therefore starting small may not have been an option."

The sizing of Monofoil was an inevitable compromise driven by run away loads as the size goes up versus the sensitivity of a smaller boat to conditions. Broadly, the last model needs a wind at rig height of between 8 and 11 knots to fly properly, ie, a range of only 3 knots, this is a tough call for testing. As the boat gets bigger this band widens so bigger makes the boat more versatile and less sensitive to weather. One thing that will not go away is the size and mass of the crew (one man ideally), more weight means higher wind for lift off so the boat was sized for single crew but has the option of a second seat in favourable conditions. A "mini Monofoil" could be built (and was going to be built until I gained a project partner with a large workshop) but would tend to be more frustrating to test.

"JH was the first to lower the bar with "Grow up or get back in your cave. This is why I would rather solve engineering problems than waste time on forums.""

Was I? What about: "Another question is:
Doesn't the recent ORMA carnage i.e. the Route du Rhum, make you wonder how these fellas could be so stupid as to not be sailing on foils with solid wings. Jeez with average speeds under 30 knts they are barely moving."


I still don't get why DG thinks that I just crawled out of the woodwork and claimed the earth. This project has been on the web in various places since at least 1999, anyone who has followed it will have seen many of the iterations that got it to its current position. Originally I would not tell a soul about its design targets for reasons that must by now be all too obvious, I was pursuaded to release these targets against my own judgment as I knew that many people simply would not handle the concept. However, the first model, in its third iteration managed 22 knots in 8 knots of breeze so I was pretty happy that it was going the right way. To go back to the Wrights, they started in earnest in about 1899, nobody in Europe believed them until 1908 (the French press called them Les Bluffeurs), they did not suffer from the internet, looks like I'm dragging my feet. The current boat may or may not deliver, it is horribly time consuming and expensive for a non-profit activity, it may not be the final boat, it is my best shot with current knowledge.

Jon.

[DGreenwood]

JH
It is going to take me hours to take in all you"ve said and process it. (the part that I get anyway)

Simple stuff to you is work to me. Like pitch yaw and roll of a wing at that angle is not intuitive. Five minutes with my head cranked over to 45 degrees and I get it.

I don't think you just crawled out of the woodwork, I was put off by the off hand way in which you make the shoulders on which you will attempt to stand look feeble.
Your efforts are appreciated. I can see that you have put alot of work into this and I don't want to belittle that. And to a certain degree I see your point about the Wright Bros. The reality is that they and many others broke alot of spruce ad tore alot of canvas before they made it a few hundred feet. They did not soar with the eagles on day one.

No.. I am the last guy to think you should aim low. Breaking the 1 mile record is not low. Hell 60 knots would cause an outrage that would have everyone demanding a retrial. I hope you go so fast they call you a cheater.

If, as you say, it is your best shot with current knowledge, then you are most definitely headed in the right direction.

And I am not the guy you have to convince of anything but I have to say I remain skeptical of your design breaking any ocean records. Please---prove me wrong, Can't think of anything more exciting than a whole new approch to boatbuliding. I'd have to start over, at my age that would be a pain in the ass, but show me how it's done.

I will be following your progress with attention and support and will root for you at the races.
DG

[Jon Howes]

To avoid excessive forum "ping pong" Here is a very truncated account of Monofoil development written hurredly in response to requests a while ago. Excuse the wooden writing style, I was busy at the time. Hope it answers a few questions. Part 3 still to be written if I ever get the time.

Jon.

[marshmat]

Interesting thoughts, Jon; I look forward to hearing more about this... well, whatever it is, as it progresses.
It certainly defies categorization, to be sure.... but it's an interesting take on the problem of going fast under wind power. Instead of taking a boat and giving it more sail and less drag, you're taking a sailplane and gluing it to the water.
As for the technical jargon.... I don't mind so much, but it does tend to confuse people... (random aside- Eurofighter Typhoon, eh? Haven't seen that thing since it was called the EFA/2000 series.)
Best of luck, Jon.

[Jon Howes]

DG,

Thanks, I appreciate the comment. I have not actually played down anyone's previous achievements it is simply that I will not get the performance that I want by copying everything that has gone before. If you have a read of the two Word docs that I have just posted you will see that much of this plainly hangs on previous work (I didn't invent aeronautics) without which it would not happen. Not mentioned in the article are many of the people that have helped along the way, mostly wife and colleagues, difficult people whose full time job is to tear aircraft designs limb from limb in the hope of making them safer. Nick Povey, who got me into this via his Speedweek efforts is a former flight test engineer, most of my direct colleagues were test pilots, systems engineers, structures engineers, software engineers etc. They were always very happy to throw rocks and make suggestions, the most common being "My god its ugly"... That was not a design objective, it just happened that way.

Marshmat:

"Eurofighter Typhoon, eh? Haven't seen that thing since it was called the EFA/2000 series"

It was briefly called the Future European Fighter Aircraft or FEFA until someone pointed out that in one European language FEFA was actually rather rude. Flight International then came up with "Five Europeans Frigging About".

Jon.

[CT 249]

CT 249
Boy oh boy, do you have me wrong! I have the utmost respect for the Moth guys. In my estimation they are the ultimate in the way things develop in this sport. Interaction and innovation based on going out and gettiing wet. There are engineers and resin jockeys building things in their garage or any high tech shop that will let them in the door. Take a look at the Moth site (At least as of a week ago) there are pics of guys proudly displaying single knot increases on their GPSs That is how it happens. Not many of them have big sponsors and they find ways to go a little faster every day. It is the same thing I love about Open class sailing. This stuff happens with Minis and is now happening with the Class 40s.
If you knew me you'd know, I will drive a long way to help out guys with novel approaches. In fact I have finished building boats on Friday at 5 and driven for four hours to work for free all weekend to help out guys with novel approaches. Many times. My family goes without my company for long periods of time so I help out with those kinds of projects.
You can't even guess how many hours I've worked for free teaching guys how to wire their boat or vacuum bag or fair a foil.

I dont need to be lectured on dissing guys with novel approaches. My family will tell you just the opposite. Guys with novel approches dont have any damn money. But they are humble and driven and have hopes and that is what draws me to help them.

I just spent a month in Europe looking at and working on boats at the Velux 5 Oceans and the Route du Rhum. I have sailed on Formula 40s, Open 60s, class A cats, Orange II and many other out of control machines. I've logged well over 150k nautical miles on big ol' clunky wood schooners and light weight rockets. I love the machines and all the technology...but it is those guys with the crazy ideas and chunk of carbon that they scrounged up somewhere to make a foil to go a little faster that I really have a soft spot for.

That is how the Mini, the Moth, International 14s and many others have driven the innovation in this sport. I want to be there when it happens.
Those ideas eventually end up at Multiplast or VPLP or Finot or Goetz or Farr.

And that my friend is why I will always question anyone who tries to steal their thunder and why I will help anyone who can convince me they have a genuine idea.

Chris
The shutup thing was a joke. And if you look at it that way it was funny. I did sincerely apologize.


DG, I think you may have over-reacted. I think the comment that I was referring to ("The moth....had not seen the kind of engineering effort that world speed records had seen. It was guys mostly building them in their garages.") can easily be read the way I, and some others, read it.

I agree wholeheartedly about the great value and style of the way Mothies and 14ers and other guys operate. It's the way I love it, too. We're losing that, to a great extent. It would be wonderful to work out how to make it as popular as it was years ago. I wonder how much the continued success of guys like Farr/Bowler and Finot is due to the fact that they started off in exactly the same backyard way?

Closest I got to it in speedsailing was making a radical (too radical) speed board years ago, and starting on a wingmast which was dumped when another regatta got in the way.

Jon, thanks for the detailed reply.

[RHough]

To avoid excessive forum "ping pong" Here is a very truncated account of Monofoil development written hurredly in response to requests a while ago. Excuse the wooden writing style, I was busy at the time. Hope it answers a few questions. Part 3 still to be written if I ever get the time.

Jon.

Very interesting reading. Thank you for sharing it. I see that you have a sense of humor about the process :)

I thought I saw a bit of the yaw oscillations you mentioned in one of the model videos. It looks like you have come up with a solution to limit them. Well done. A free flying or sailing model is much harder to design than one that is piloted. What is most impressive to me is that the model performs despite of the gradient problem close to the surface, not because of it. It will be very interesting to see what the final compromise on foil area is at full scale.

I too, hope that you enjoy success with the Monofoil. I'd like to see the Monofoil beat both the windsurfers over 500m and 1M and the lead mines over longer distances.

[PI Design]

Thanks for posting all that background Jon, very interesting.

Would there be any benefit to adding WIG/ekranoplan style wings to the boat, to generate additional (vertical) lift? I figure this would allow you to use a smaller sail. You probably know more about WIGs than I do, but I'm imagining some sort of Lippisch inverted delta wing with the unusual (not NACA) section.

[Doug Lord]

Jon, thanks for sharing so much information!

[DGreenwood]

Great Reading Jon...although once again it will take me forever to get through it.

CT 249
It is still going on.
Lifting rudder foils starting to appear on Minis came from some of Paul Biekers work on Int 14s and could appear on larger stuff someday.(although a little too vulnerable for ocean stuff). How about the chines you are seeing on the Minis, the Volvo 70s and now the Open 60s...once again they saw much development in 14s. The US military were messing around with powered monofoil stuff (I don't know if they still are) I suspect they were paying some attention to what the Moth guys were doing. Sail and rig development are effected by what goes on in those classes. Those designers and builders, particularly in France and UK, are staying involved with these classes because they are where ideas sprout.

Enough of hijacking this thread. Back to the Monofoil.

[water addict]

To avoid excessive forum "ping pong" Here is a very truncated account of Monofoil development written hurredly in response to requests a while ago. Excuse the wooden writing style, I was busy at the time. Hope it answers a few questions. Part 3 still to be written if I ever get the time.

Jon.

Jon,
Thanks for the write-ups, good info, interesting reading. Of course I will offer my unsolicited opinion, which emerges from a dark, dank place somewhere in the vicinity of my posterior...

I was quite skeptical at first, it seems quite a complex machine. I like it though. It could be a speed breaker in somewhat mild conditions.

Still not convinced about a distance ocean passage at high speed. Dynamics of riding and slamming over big waves seems scary. Loads of a sizeable slug of water smacking into the structure at high speed seems like a tough issue too. I don't see any way around that, it's not a matter of if, but when, if you are in the ocean. I'm not saying you have not thought this through, but the ocean passage stuff, I'm not convinced.

Good luck. I'd like to see how full-size prototype does.

[Guillermo]

Grow up or get back in your cave. This is why I would rather solve engineering problems than waste time on forums.
Jon,
I really appreciate your postings here, and probably all of us will learn a lot from you as you're the one doing the thing. But I recommend you to take things in an easier way. You'll learn that here (As I and others have done), if you want to publicly discuss your ideas. But, for sure, you are absolutely free to "get back to your cave".... ;)

Cheers.

[DGreenwood]

Aahh Guillermo He was just ticked off cause I was digging at him.
That was aimed at me but my skin is thick. I probably deserved some of it.
I know your intentions are good but I'd just as soon see that fire die out. Please?

By the way I was looking at the Google sat image of Pontvedra and I saw a yacht marina there. Do you know how deep that is? Looks like small boats. If you like, respond by personal message so as not to Hijak the thread
Thanks

[Vega]

Jonh Howes, I was impressed with your model and I am even more impressed with the path that you have crossed till you have managed that working model.

I am a sailor, but also an airplane pilot and clearly in that machine (I have difficulty in calling it a boat), aerodynamics plays a large part.
When I saw that model speeding, I have thought that it would be a lot of fun flying (not sailing) that thing (dangerous too). I guess that machine attracts more to the pilot in me than to the sailor…but perhaps it can represent the best of both worlds in the future, a Hydro-Glider, the perfect machine for the ones that like to sail and to fly:) .

I have foreseen some problems but you have already gone through them. Of course, you are going to go through a lot more when you do the real thing.:p

Best of luck, and please, keep us informed (when you can, post the 3rd paper, I am curious and very interested).

regards

[gggGuest]

How about the chines you are seeing on the Minis, the Volvo 70s and now the Open 60s...once again they saw much development in 14s.

Not really. All that development was done in the Antipodean lineage classes, the three skiff classes, NZ Javelins, and Cherubs principally. The i14s were way behind from about 1965 right up to the amalgamation and beyond. That's not to take anything away from current generation 14 designers and Paul Bieker especially who has done a tremendous job in taking the lessons from what were the more advanced classes, adding his own ideas and helping to bring the 14 back so that its pretty much state of the art now after decades when it was way off the plot.

[Jon Howes]

Water Addict:

"Still not convinced about a distance ocean passage at high speed. Dynamics of riding and slamming over big waves seems scary. Loads of a sizeable slug of water smacking into the structure at high speed seems like a tough issue too. I don't see any way around that, it's not a matter of if, but when, if you are in the ocean. I'm not saying you have not thought this through, but the ocean passage stuff, I'm not convinced."

I entirely agree that this is to be proven. What we have at present is a small sprinter on the stocks, this is certainly good for the 500metre and one mile attempts. It is designed for peak to trough wave heights of four feet at full design speed, slowing down will allow bigger stuff to be handled.

A small model has sailed in surprisingly rough water (this was a big surprise to me as the waves where about three times the design wave), what it did was skip the foil from wave crest to wave crest, each time the foil re-entered the boat accelerated followed by coasting to the next wave crest, it did come a cropper a couple of times but recovered and went on until it piled up sufficiently for me to retrieve it. This was way beyond its design limits.

Our thinking is that the current boat would at least be good for an attempt on the Round the Island course record (Isle of Wight for non-Brits). This would at least tell us how she goes in more representative conditions. If we have the speed a lot of water can be covered in daylight so round Britain may also be a possibility if the boat can be shown to be reliable at lower speeds during darkness. In general, offshore sailing will be a steady development as has been the development of the boat itself. Big boy offshore stuff will need a bigger boat. Issues are that lying ahull in this thing would be nasty, it is very hard to reef a wing, it has to be streamed with zero or low incidence in which config it has lower drag than a mast but MUST be kept streaming to the wind or the forces run away fast. Against this, with the foil to weather and the wing streamed like this everything is very stable. Ideally however, it has to keep moving. Another possibility is that it should be fast enough to be able to pick its weather to a degree. It is not a certainty, it is something to be worked on.

Jon.

[boogie]

hi jon,

i really like your out of the box thinking and wish you all the best for your project.

the one thing that surprises me looking at your design [and it's only a gut feeling] is that the wing looks very small compared to the size of the complete vessel... including all the beams, crew pod, air rudders, foil and so on.
i'm sure you have done your calculations, but i guess we will see when it hits the water.
i don't think the size of the wing will be a problem at high speed due to the apparent wind, but for getting going and getting up to a speed where the apparent wind will really kick in, i don't know.

i'm really curious on one other aspect of your design. the foil.
i guess for the speed you are aiming at you will have to work with supercavitating or ventilated foils.
how do you plan to overcome the inefficiencies of these types of foils until the speeds where they work better than "normal" subcavitation foils?
i guess somewhere around the 40 to 50kn mark....


i'm into speed sailing myself on windsurfers and kitesurfers. i'm not a good enough rider to go for any records on my choices of craft as a rider myself [still stuck at 35kn over 500m and 39.7kn for peak speed], but i have been designing and building fins for windsurfers and a couple of kite speed boards that managed to get to 44.8kn over 500m and several peak speeds into the 46/47kn range.

i really like the simplicity and full scale development of wind- and kitesurfers.

on my windsurf fin designs i think i have the cavitation under control into the low 50kn range by using very thin foils [5-7%] and 30deg sweep.
kiteboards being essentially ventilated foils itself don't have that problem of course.

please keep us posted on the progress of your project.

regards
boogie

[Jon Howes]

Hi Boogie,

The wing in the CAD drawing is optimised for speed as you surmised. The one we have built is a little bigger, 15 sq metres rather than 9sq metres as on the CAD model. We did this for exactly the reason you mentioned, ie, to get going as it widens our test wind speed range. Dependent on results a second smaller wing will be built but we may not need it as I could easily run out of bottle before this becomes critical!

The foil is a ventilated design and it is designed for a CL of 0.2. The section (ie 2D) L/D ratio is 22 which is low compared to a conventional wing section but it is consistent in behaviour. The high speed bit is just the tip, the bit above this has wider chord and is immersed at lower speeds when more foil is needed. A horizontal spur foil is used to fly the foil assembly partially out of the water until the spur planes on the surface with just the foil tip in the water below it.

Jon.

[messabout]

For the history minded; An ancient fore runner of this machine was described in a book of the late 1950s. The Book was titled; The 40 Knot Sailboat. The author was a US Navy commander assigned to the Bureau of Naval Ordinance. He made models of a type that seemed outrageous at the time. Smith, I think his name was. He reckoned that the reason a boat has limited speed is that the hull is in the way. That led to his foil program. That surely must make him one of the early foil afficianados. One of his model testing places was the reflection pool in Washington D.C. His models worked after a fashion. More than one of them had a winglike structure that indeed provided some lift when at speed.

[Kiteship]

Both Ketterman's Trifoiler and Cunningham's YP Endeavour were conceived and built as models, worked very well as models, then scaled quite successfully to full size. Both immediately increased their respective class records by huge margins (20-30%, not the measly 0.05% more typical of "modern" sailboards these days)

There are perfectly good reasons for modeling to be successful and perfectly good reasons why they often fail. It is not a coincidence that the same guys who understand things like scale effects are the same guys who go on to break records. "Experimenting at full size" is a perfectly acceptable form of R&D, if you can foot the bills. For others there is CFD. For yet others there are models. Hate the player, not the game, eh?

Interesting that you credit Drake with sailboard world records, when 1) he copped the original idea from another inventor and 2) there were some 1+ million "iterations" of the device--all built by others-not-Drake--before world records fell (and another million or more iterations before boards recaptured the outright record from YPE).

Dave

Doug, scale models can be very helpful. However, I was just saying that the fact that a model works does not mean that a full-size boat works. Look at Bernard Smith's work; even the webpages for his book readily admit that ideas that worked in his models did not work in the full-size craft.

Frank Bethwaite went to Smith and watched his videos and spent 20 years and 19 full-size boats trying to get his concepts to work. He didn't succeed. He found that the Smith concept needed too much sail to lift off onto the foils and notes that "Bernard's tiny balsa models had been so light (the cube/square law in reverse) that he had not been faced with this problem".

So all I'm saying is that success in model form does not PROVE success in full size form will follow. Hell, Farr, Bowler, Jackson, Murray and many other designers have found out you can't scale a 12 foot dinghy up to 14 feet or 18 feet long. Spencer found you can't use a 26 footer as an infallible test for a 62 footer. A scaled up butterfly could neither respirate or fly. Scaling effects matter, we all know that. You can't even scale up a fast speed board to make a fast big windsurfer.

That's not saying that models aren't great tools for design, I'm just pointing out that the evidence is that they are nothing like infallible.

[Kiteship]

Sorry I didn't discover this thread 2 weeks ago. Some random comments:

Still not convinced about a distance ocean passage at high speed. Dynamics of riding and slamming over big waves seems scary. Loads of a sizeable slug of water smacking into the structure at high speed seems like a tough issue too.

Be a shame if the design only beat the various flat water outright records. That'd destroy my confidence in the man altogether, don't you agree? :-)

We can all recognize hype when we see it. DG has real life experience with high speed sailing, we don't know if you or JH do.

I must have missed this part; only heard him say he'd been "taken" by "earlier charletans" or similar. Is it true, DG, that you have speedsailing experience? Which boat(s) and what years? Not trying to pin you down, DG, but as you said yourself, nobody here should deign to pass judgment on speedsailing designs without personal experience--lots of it, I believe was your gist. Will you provide us your own specifics, please?

That class (moths) had not seen the kind of engineering effort that world speed records had seen. It was guys mostly building them in their garages.

DG's already been jumped on for this comment, but I believe I have a new slant on it--what makes you think that outright speed record teams have spent, or have access to, large engineering resources? The Cunningham crowd are famous for their "bare bones" approach; Ketterman built his boats out of his own pocket (as did Coleman with Crossbow--though slightly deeper pockets). The very concept of "sponsored speed attempt" is widely regarded as an oxymoron within the genre--unless you happen to be riding a big board manufacturer's product, and then it's more a style play than engineering.

Where they less developed a few years ago and was that responsible for the failure of his (and Frank Bethwaite's) full-scale boats to live up to the performance of his models? I know FDB lacks your formal qualifications but he does have significant experience in sailboat design and many years of full-scale work with boats inspired by Smith. May I ask where you think he went wrong in his attempt to apply these ideas?

Though I'd dearly love to meet the man and I wish to take nothing away from his monohull accomplishments, there are numerous errors in Bethwaite's book (cf pumping, which he completely misunderstands). From the presentation and (lack of) engineering presented regarding his whole multihull project therein, it's pretty clear the project was more to "prove" the "superiority" of skiffs than to do any real testing of multihull concepts.

Cheers,

Dave

[water addict]

Sorry I didn't discover this thread 2 weeks ago. Some random comments:



Be a shame if the design only beat the various flat water outright records. That'd destroy my confidence in the man altogether, don't you agree? :-)


Cheers,

Dave

I see of course you meant this tongue in cheek, but yes if the flat water records were broken it would be a significant acheivement. There was the claim that the rig could beat ocean passage records as well, and of this I am a bit skeptical. I think rough conditions might be a bit much for it. But I respect the idea, and not saying it can't be done.

[CT 249]

Both Ketterman's Trifoiler and Cunningham's YP Endeavour were conceived and built as models, worked very well as models, then scaled quite successfully to full size. Both immediately increased their respective class records by huge margins (20-30%, not the measly 0.05% more typical of "modern" sailboards these days)

There are perfectly good reasons for modeling to be successful and perfectly good reasons why they often fail. It is not a coincidence that the same guys who understand things like scale effects are the same guys who go on to break records. "Experimenting at full size" is a perfectly acceptable form of R&D, if you can foot the bills. For others there is CFD. For yet others there are models. Hate the player, not the game, eh?

Interesting that you credit Drake with sailboard world records, when 1) he copped the original idea from another inventor and 2) there were some 1+ million "iterations" of the device--all built by others-not-Drake--before world records fell (and another million or more iterations before boards recaptured the outright record from YPE).

Dave

I don't credit Drake with speed records. I said he created the style of craft that holds the record.

I can't see the relevance of the fact that Jim went back to his succesful career in science and didn't design the boards that broke the record.

You say he "copped the original idea from another inventor". He denies this; "I had no knowledge of these two earlier efforts at the time" he said to "Wind Surfer" magazine3 and to others. I get the feeling he may know.

If you're referring to Newman Darby's ideas, standing on the lee side and leaning against a square sail seems very different to standing on the windward side of a "normal" sail hanging onto a wishbone. The fact that the Windsurfer patent fell in the UK has been used as an example of poor patent drafting which obscured the fact that the Drake/Schweitzer board was, in fact, a considerable inventive step. If Drake had known about the Chilvers and Darby boards he would probably have been able to draft a patent that would remain valid even when that prior art was brought up. Your case demands that he knew about the earlier boards; that he is publically lying on record about that fact; and that despite knowing about the prior art, he made no attempt to ensure that the patent was drafted to remain valid despite it. Big call.

I agree that model tests can be very useful. Of course, scale effects can be accounted for. However, the fact that there are such significant matters as scale effects to work through, is the reason that some people don't want to just assume that the real thing will work from a model. Surely Smith, a physicist, knew of scale effects? But why didn't his full scale efforts work?

Sure Cunningham worked from models. The Cunninghams had done so for years; their C Class cats were tested in irrigation ditches. Charlie used to carve boats from sticks and play with them in the water tank when he was a little kid. However, the Cunninghams had also lead the way in dinghy design in the '40s; lead the way in cat design in the '50s and '60s; won the Little America's Cup; etc.

Winning so many races proves that the Cunningham team really know their full-size real-world stuff. But when we are presented with teams who don't have decades of experience in winning world-class races, why should we assume that they can take a concept from model to full size just as well as the Cunningham team can?

The Cunningham team has also got it wrong, like with their canoe sterns (derived, I think, from their model tests). Once again, it seems like more proof that just because someone shows us a working model, we shouldn't merely assume that the concept will work full size. That's about all some of us are saying.

[Chris Ostlind]

The fact that the Windsurfer patent fell in the UK has been used as an example of poor patent drafting which obscured the fact that the Drake/Schweitzer board was, in fact, a considerable inventive step. If the patent had been drafted well enough it would have remained valid.

Not necessarily so, though most laymen would love to believe that.

Once you get your butt into court and present your stuff to a jury/judge/whatever, you enter the realm of the crap shoot in its highest form. Sure, the lot can go down the tubes if the original series of claims was not presented well, but it has a whole lot more to do with the cleverness, resourcefulness and presentation skills of one's attorney, once you take your seat in that room.

There are tons of court records in this country, alone, in which a patent was found to be bunk when, in fact, it was as clear as one could make it as to the originator of said claim.

[Doug Lord]

Jim Drake-inventor of the windsurfer-has just joined this forum; it would be great to hear his comments...

[CT 249]

Not necessarily so, though most laymen would love to believe that.

Once you get your butt into court and present your stuff to a jury/judge/whatever, you enter the realm of the crap shoot in its highest form. Sure, the lot can go down the tubes if the original series of claims was not presented well, but it has a whole lot more to do with the cleverness, resourcefulness and presentation skills of one's attorney, once you take your seat in that room.

There are tons of court records in this country, alone, in which a patent was found to be bunk when, in fact, it was as clear as one could make it as to the originator of said claim.

Yep, I shouldn't have said it "would" have remained valid, but that it "could" have remained as the next sentence said.

By the way, in no way am I a layman in the law. And I've spent days in court watching the windsurfer patent go down. Presentation skills etc count for a lot less in jurisdictions were patent cases are decided before a judge.

[MalSmith]

Winning so many races proves that the Cunningham team really know their full-size real-world stuff. But when we are presented with teams who don't have decades of experience in winning world-class races, why should we assume that they can take a concept from model to full size just as well as the Cunningham team can?



One thing you can do is to have a look at the mathematical modelling used to scale the results. If the assumptions seem reasonable, then there is a reasonable chance that the full size results will reflect the predictions, at least to some degree. If you think the assumptions are flawed, you can probably make your own predictions. If there is no mathematical modelling at all, then skeptisism is a reasonable attitude to take.

Admittedly, being able to do the maths and make the right assumptions comes with experience, but it needn't necessarily be direct experience with the product you are designing.

Mal.

[CT 249]

Thanks for the info.

Just to underline it; I (and I think many other people) have got no problem with the idea that it's certainly very, very possible to get enormous benefits from models when they're used the way you say.

[PI Design]

The classic NA case of scaling proving difficult is the fact that Reynolds Number and Froude Number scale at difefrent rates. It is not possible to produce a replica model that operates at the correct Fn and Rn values. The common solution is to attach studs to the bow region to artificially increase the Rn. There are many other examples of scaling problems. For model testing to be truly benefical, these need to be known, understood and accounted for. If they are, model testing can be very useful. if not, you get a surprise!

I hope Mr Drake made his fair share from the Windsurfer, but I guess its true that there are many, many more around due to the lack of patent allowing other designers to evolve the concept.

By the way, on back to the original topic. The sailrocket project (sailrocket.com) is a similar concept. It will be interesting to see how the two fare against each other, if they get built.

[Jon Howes]

PI Design Wrote:

"By the way, on back to the original topic. The sailrocket project (sailrocket.com) is a similar concept. It will be interesting to see how the two fare against each other, if they get built."

Sailrocket is an unashamed development of the Bernard Smith concept.

Differences between Sailrocket and Monofoil:

Sailrocket has the longitudinal CG way behind the aerodynamic centre (Neutral Point) and relies on water contact for pitch stability.

Monofoil has the CG ahead of the neutral point and is aerodynamically pitch stable

Sailrocket has a rudder and a canted foil, both of which must work for directional stability/control

Monofoil has a single foil and steers by relative movement of aero and hydro force lines (hence the name). Monofoil is directionally stable about this single point of water contact

Sailrocket has a sheeted control for the wing which means that any pitch change of the vessel results in a change in the incidence of the wing, this makes the wing potentially destabilising if water contact is lost.

Monofoil has a free-feathering wing controled by a servo tab. The wing does not affect pitch stability

Sailrocket uses a conventional foil which uses the hull as a ride height control

Monofoil uses a ventilated, cranked foil unique to each tack, ride height control is a function of foil geometry and body running angle.

Both Sailrocket and Monofoil heel to weather but Monofoil lifts the body clear of the water as it does so. Body pitch angle trim changes also trim the foil (obviously) and allow foil ride height to be controlled, these trim changes do not affect the wing or the force it creates.

Sailrocket is single tack

Monofoil is equal on both tacks

Other than the canted rigs and the heeling to weather there is actually very little in common between the two craft.

Jon.

[PI Design]

Thanks for that Jon. I knew they were slightly different, but didn't realise how much. Still, they do work on a vaguely similar concept...

Going back to an earlier question of mine, is there any merit in attaching WIG-style low aspect ratio wings to get the hull to fly earlier? This would allow you to use a smaller sail, so you could sail in stonger winds. Just a thought, I could be way of the mark and showing a total misunderstanding of the design.

[Jon Howes]

The way to fly in lighter winds is to fit a bigger wing. We have found that the transition from planing to flight is very smooth and progessive however and partially wing-borne operation is a perfectly viable way to sail.

Wing in ground effect craft are one of those apparently attractive concepts that is easily mis-used. The reason that they get such a benefit from ground effect is that they are low aspect ratio, short span aircraft in the first place and induced drag is much more evident than it will be for (say) a sailplane. This makes the ground effect cushion much more noticeable although a normal aircraft may actually carry the same payload for a lower specific fuel consumption. They are very attractive as military vehicles however as the stable, very low altitude flight at decent cruising speeds is potentially very stealthy. A case of horses for courses.

Jon.

PS: I just noticed that I misunderstood your question! Early flight was helped on the first models with a small hydrofoil under the nose (which also avoided pitchpoling during acceleration from rest). As the hull forms have improved the partial planing/flying mode is easily reached so there is little need to help an early take-off.

[Chris Ostlind]

By the way, in no way am I a layman in the law. And I've spent days in court watching the windsurfer patent go down. Presentation skills etc count for a lot less in jurisdictions were patent cases are decided before a judge.

Haven't passed the bar exam? No J.D. degree? That equals layman, no matter how much time you've been in a court room. The Court Clerk is a layman, the Bailiff is a layman. They're all laymen except the practicing attorneys and the judge. But that's a minor point, really.

Truth is, any time one human being puts their argument before another human being, all the subtle and nuanced functions of style, prep, clothing, grooming, intonation, etc., etc., enter the picture. The practice goes well into how big should the display charts be in a given setting, what colors should be used for salient points and on and on. If these things didn't matter, there'd be no need for salesmen for anything. The products would simply sell themselves based on pure data as presented. Patent haggles do not escape the process.

There isn't a judge or jury alive who is not affected by that process. It's this simple observation that gives functional purpose to the craft and science of jury selection consultants, practice trial scenarios, sample jury test runs, etc.

When there's big money on the line (and what other scenario would logically qualify in the pursuit of a patent hassle? Pride? Arrogance?) the side that ignores the above mentioned realities will be muttering to themselves as they leave the courtroom. Call it tools of the trade, or anything you like, but lack of thorough preparation will send you to the back of the pack virtually every time out.

[Chris Ostlind]

They are very attractive as military vehicles however as the stable, very low altitude flight at decent cruising speeds is potentially very stealthy.

They're also really easy to shoot down with small arms fire.

It's not good when a $40+ million aircraft is lost to a 4 cent bullet. It's one of the key reasons why Apache attack helicopters are flying severely restricted mission support in Iraq right now. (among other reasons)

[PI Design]

There isn't a judge or jury alive who is not affected by that process. It's this simple observation that gives functional purpose to the craft and science of jury selection consultants, practice trial scenarios, sample jury test runs, etc.



Surely America is the only country daft enough to allow the jury to be hand selected...:rolleyes:

[Jon Howes]

"They're also really easy to shoot down with small arms fire.

It's not good when a $40+ million aircraft is lost to a 4 cent bullet. It's one of the key reasons why Apache attack helicopters are flying severely restricted mission support in Iraq right now. (among other reasons)"

Sounds like you like them about as much as I do! I'd rather have a decent aircraft.

Jon.

[Chris Ostlind]

You might say that, Jon. I was in two helicopter crashes while in the military. While I have an aversion to them personally at this point in my life, I do see their value for certain, mission specific, assignments. One simply has to be willing to assume the risks (and costs) associated for the expectational gains.

It's the vast accumulation of maintenance intensive, fiddly bits that gives me pause. I think it's the obligation of every designer to remove as much of the "extranea" as they can while they advance the art. Unfortunately, most of the existing design paradigms do not fully address that philosophy. The result is, we are further removed from our interpersonal contact with said wonderful new object in our lives.

At one point, this race to embrace technology will so far exceed the human capacity to participate that it will only serve itself. Won't that be an interesting dilemma? Didn't Ahhnold do a couple of movies about that potential?

[Jon Howes]

Chris,

I was actually referring to Wing In Ground effect craft but your point about helicopters is well made (Helicopters don't actually fly, they're so ugly that the earth stays away).

While I worked for the CAA here in the UK I was involved in various airworthiness rulemaking activities and it was clear that the rotorcraft fraternity had a very different take on aircraft safety than the fixed wing crowd. One memorable exchange went along the lines of:-

Rotorcraft engineer: "We don't want to be tarred with the fixed wing brush"

Airworthiness specialist: "What, you mean with their ten-times better safety record?"

I tend to think of helicopters as being hugely attractive aircraft when viewed from a liferaft looking up however, although for fun I would rather not fly an aircraft with blurred wings...

Jon.

[marshmat]

Jon, if you want more ammo against helicopters.....
The military up here decided some 40-odd years ago that maybe we should put some choppers on our boats. Enter the Sea King. In recent years it has definitely earned the name Sea King.
http://findarticles.com/p/articles/mi_hb3542/is_200303/ai_n8357853 for one story on them.... http://www.cbc.ca/news/background/cdnmilitary/seaking.html ..... Google will turn up plenty more.
Maintenance to active time is now at over 30 man-hours of repair for every hour of airtime on these things.

[Kiteship]

CT249, you often use a pair of debate tactics which would get you thrown off any junior high school debate team. Extrapolate to the ridiculous and reduce to the ridiculous. If I "insult" your intelligence, I have insulted every designer, sailor and boat owner who ever lived (the first) and if you can find widespread counter examples--even if flawed--you have conclusively "proven" your point (the second). You may be unaware you are using these devices, but I rather doubt it.

Doing so makes it tiresome to correspond with you, though I often take your point and would love to continue the conversation (I renew my offer to buy the first round of beers, whenever we share a continent next). If you'd take a bit more effort to address the issue and less time trying to "score" points and win arguments, I for one would enjoy the experience more. (Comments such as "I take your point, however..." are often especially appreciated) You have infinite permission to say anything you like, of course, just like any other poster. I don't offer the above as a command, only a suggestion. (And yeah, I know I'm gonna get slammed by Water Addict and others for saying this, but it doesn't make it any less valid, IMO)

As to Jim Drake's position; he has told me that he didn't know about earlier windsurf-like devices, too, and I believe him. Jim is a very nice man. It has also been determined that he had access to both Popular Science and to AYRS magazines prior to his invention, both of which ran feature articles on the earlier devices. It is not unusual to read about something, honestly forget entirely, then later use the pool of "general knowledge" resident in all of us to re-create the earlier thing, unintentionally.

All inventors understand this. There is also another concept--that multiple people working on an identical challenge will devise similar solutions, and yet a third which says that the simple knowledge that a thing has been done--with no details of any sort--is sometimes sufficient to "spark" a similar--even identical solution. Last, it matters not one whit whether Jim stole the idea outright or honestly invented the thing from dot zed. It was ruled to be in the public domain, thus not susceptible to patent protection.

As you (sort of) mention, it is perfectly legal to patent an improvement to an earlier device--patented or not--and claim patent protection for those improvements. Jim's mistake, almost certainly unintentional, was not to do this. You can be sure he regrets it.

Last, regardless of your thoughts and opinions--which I respect--the patent was negated due specifically to the earlier Darby and other devices. Call if unfair if you like, but we are nations of laws not popular opinion; the same law which protects one valid patent holder's rights takes those rights away from another. Both positions are a crapshoot in court, absolutely, but them's the rules we play by. It's no use wingeing about it; play or don't play, the choice is always the players.'

Dave

[gggGuest]

Though I'd dearly love to meet the man and I wish to take nothing away from his monohull accomplishments, there are numerous errors in Bethwaite's book (cf pumping, which he completely misunderstands). From the presentation and (lack of) engineering presented regarding his whole multihull project therein, it's pretty clear the project was more to "prove" the "superiority" of skiffs than to do any real testing of multihull concepts.

I really have to disagree with you big time there. I should really wait a week before posting it, because I have some info promised on the HSP project, but never mind. But assuming that what's in the book is what actually happened then that surely cannot be the case.

When Bethwaite started the HSP project he had, as far as I can tell, no contact with the skiff people at all. His background was from NZ and in straightforward low power dinghies. I'm not sure that he got involved with the skiffs much until at least the late 1970s or early 80s when Julian, his younger son got involved with them. Julian's elder brother and sister (FD, Laser, 470, Yngling etc at championship and Olympic level) don't seem ever to have had any involvement in skiffs.

Then we have to consider the sheer scale of what he did. Twenty two prototypes starting with asymettric proas with inclined rigs, and not getting onto the planing main hull/tip floats semi trimaran format until about the 15th. Its got to be one of the most sustained efforts in something different in sailboat design, there's no way it was just an attempt to prove the superiority of skiffs, especially as the end product is in no way a skiff relation anyway. The skiffs have quite different dynamics. Now to spend that much effort to prove the superiority of something you weren't involved with in the first place sounds monumentally crazy to me, and he's not that... And incidentally doesn't that make him one of the few people to have made a planing multihull work. Bethwaite may not like calling the HSP a multihull, but it is in my book.

Now I'll agree with you that he never evaluated true catamarans properly, nor ever seems to have sought to do so. The project started with evaluating the Bernard Smith concept, and he ended up considering that the concept doesn't really work in practice. In front of me I have a photocopy of an article from David Pelly on Speed Week in 1988 and I quote "Some day someone will succeed in making a sloping rig boat work" and then goes on to catalogue a collection of failures by sloping rig boats that year...

I think if it can be made to work it will only work in the speed week context of get the perfect gust and ride it, like, say, Sailrocket, and 500m speed records, rightly or wrongly, is something Bethwaite never seems to have been interested in.

[Doug Lord]

Jim, Bethwaite did describe the HSP as a trimaran
and ,of course, it was a very fast planing multihull. When you get more please post it!
Of course, if the "ama's" hadn't been shaped like hulls maybe it could have been a monohull with buoyancy pods?!
(p185 of THE BOOK)

[CT 249]

Haven't passed the bar exam? No J.D. degree?

Haven't passed the bar exam? No J.D. degree? That equals layman, no matter how much time you've been in a court room. The Court Clerk is a layman, the Bailiff is a layman. They're all laymen except the practicing attorneys and the judge. But that's a minor point, really.

Truth is, any time one human being puts their argument before another human being, all the subtle and nuanced functions of style, prep, clothing, grooming, intonation, etc., etc., enter the picture. The practice goes well into how big should the display charts be in a given setting, what colors should be used for salient points and on and on. If these things didn't matter, there'd be no need for salesmen for anything. The products would simply sell themselves based on pure data as presented. Patent haggles do not escape the process.

There isn't a judge or jury alive who is not affected by that process. It's this simple observation that gives functional purpose to the craft and science of jury selection consultants, practice trial scenarios, sample jury test runs, etc.

When there's big money on the line (and what other scenario would logically qualify in the pursuit of a patent hassle? Pride? Arrogance?) the side that ignores the above mentioned realities will be muttering to themselves as they leave the courtroom. Call it tools of the trade, or anything you like, but lack of thorough preparation will send you to the back of the pack virtually every time out.
Reply With Quote

Got the degree? Yep. Got the post-grad qualifications? Yep. Admitted? Yep. Working? Yep. Layman? Nope.

Yep, being good when you're up on your back legs in court is a help, but it's not as good as having the law and facts right.

[CT 249]

Kiteship, I appreciate your points. This is an internet chat room, I don't spend a lot of time honing arguments. I do get careless in here, I have said that quite a few times. I do get rather hot-headed when people seem to intimate that most sailors or designers, and the best sailors and designers, are overly conservative or get it so wrong so often. I have never seen any evidence of this. I do feel that excessive criticism of successful current boats is damaging to the sailing scene, which IMHO needs other much more important changes if the health of the sport is to revive. This does affect my arguments at times. Some of my counter examples may be flawed, but I think that you just throw many of them into the "flawed" pile because they refute the case you are trying to present.

Having said that, I think you may also have some imperfections in your own arguing style too. Saying that because modern planes (300-2000? knots) are enclosed, 30 knot yachts should be enclosed sounds to me a lot like using ridiculous examples. You are also ready to impute motivation for Bethwaite's long-term project with absolutely no evidence. Frank loves the HSP, and I think his new boat is a multi. You stated that Drake "copped the original idea from another inventor" when there is absolutely no evidence that he did; just your assumption that he read about the earlier inventions in publications he had access to, and then forgot about it. That seems to be two leaps of logic that would see your high school debating teacher wagging his finger at you, too.

I find it a bit tiresome (albiet interesting at times) to chat with you, because in the past, you have shown a tendency to ignore facts disproving your case. Case in point, an old SA thread where I pointed out that most people sail old boats and your reply included the line "Sure, there is a burgeoning Star class, with new-ish boats coming online all the time, but do those new-boat numbers more or less equal new 49ers hitting the water, at about the same cost? If not, your argument seems to fail."

I then gave ISAF figures that showed that the Star numbers DID more or less equal new 49ers hitting the water. Therefore, my argument did not fail. And did you say "I take your point, however".....? No, you then said that you would "find some useless statistics to beat you about the head and shoulders with."

You proposed numbers as a test, then referred to those same numbers as "useless statistics" when they were shown to hurt your case. How would that go down in school debating?

I'm not whinging about the fact that the Windsurfer patent went down. I said Drake invented the windsurfer. Common language does not have to reflect the results of legal decisions. Everyone in the legal field knows that the lawyers sometimes get it wrong, especially when (as can be argued with the Windsurfer case) the legal advice involved may be bad. We get lots of engineers etc saying the lawyers get it wrong, why can't we say the lawyers got it wrong when it was decided that Schweitzer and Drake didn't invent the windsurfer?

[water addict]

.......stuff to CT249...... If I "insult" your intelligence, I have insulted every designer, sailor and boat owner who ever lived (the first) and if you can find widespread counter examples--even if flawed--you have conclusively "proven" your point (the second). You may be unaware you are using these devices, but I rather doubt it.

....stuff....
Dave

I know of at least 3 people, Kiteship, that you have insulted on here, myself being one of them. And I can surmise from numerous other posts on this site that you have insulted more. Gotta wonder when everyone else is wrong and you are the only one who seems to get it.

Then again maybe not. Perhaps you are on the level of other revolutionary thinkers, and it is just my ignorance preventing me from overlooking your enlightened communication style.

[PI Design]

Looks like Sailrocket has stolen a march on Monfoil. http://www.yachtsandyachting.com/news/?article=135526
Monofoil seems in many ways the better design, but is further from reality at present.

[Jon Howes]

"Looks like Sailrocket has stolen a march on Monfoil. http://www.yachtsandyachting.com/news/?article=135526
Monofoil seems in many ways the better design, but is further from reality at present.
12-11-2006 12:42 PM"

Good luck to them, they are nice people and they have worked very hard for it.

Jon.

[boogie]

that's awesome that sailrocket found the money to go there.
i guess they have done their homework, but i always thought the winds down there are best in spring and summer...

i'm sure we'll see rapid improvements from sailrocket in the next few months.
but they've got a loooong way to go in regards to prove that their boat is up to record speeds. by the time they are getting there the bar might be raised to a whole new level with the european windsurf and kitespeed season coming up.

jon,
how far is your project off for hitting the water?
i would be very keen to see your craft in action. there are still a few things about your concept that i can't quite get my head around... like steering it properly with a single foil in the water.

all good stuff and like a thriller to watch and follow.
boogie

[PI Design]

A real bad week for Sailrocket. The boat was totally uncontrollable by the sound of it and is now in several pieces. Whilst I know very little about either project, it is these control issues that Monofoil seem to have considered in greater detail.

Good luck to all trying to break 50kts. There seems to be a real race on to break this barrier, and its exciting to watch.

[Jon Howes]

Some thoughts on this, without any guarantee of being correct!

Monofoil has two key features that are relevant here:

1: A free feathering, mass balanced rig

2: Stable about a single point of water contact in all three axes

1: The rig. If the rig has a sheeting angle constrained with respect to the foil incidence the boat has one stable course. If the boat is off course, then due to the large separation of foil and rig, big forces are needed to force the boat to remain on course. This was anticipated and then tested on monofoil model four by fixing the rig incidence (jamming the rig pitch pivot). The boat could be entirely steered by sheeting angle. A free feathering rig is just a force producer and it always (if mass balanced) stays in its low drag zone.

2: I have always been nervous about boats that sail fast and rely on two points of lateral resistance. Big yaw couples can build rapidly if yaw balance is not achieved by aerodynamic balance and Monofoil only sets the single foil yaw angle relative to the rig position (the fuselage is slaved to the foil angle, ie, points the same way). Monofoil does not have a rudder, either air or water, it has a servo tab at the back of the fuselage to provide aerodynamic force to change the cross-boom angle and hence the foil to rig angle. Control forces are therefore very low (relatively) and rudder loading is not an issue as it does not have one.

At a first look (1) looks like a strong culprit with a bit of (2) as well in that a second, highly loaded, surface is required for course keeping.

Could all be rubbish of course as we have not run Monofoil at full scale yet and cannot until we get some money from somewhere. I hope they fix it, find the problem and move on.

Jon.

[Matth]

Jon; can you reveal any details about the superventilating foil? I would be very interested in the shape, and how well it transitions from low speed to full ventilating operation. What sort of L/D are you seeing, or expecting?
Matt

[Jon Howes]

I will try to post an image of the section and its coordinates, not now, it is too late at night!

It is actually quite simple. The pressure face does all the work, the "suction" face has a zero pressure coefficient, ie, it is a bubble surface. Aft of the trailing edge the pressure coefficient of the pressure face is also zero, ie, another bubble face. As the "suction" face does no work it can be cut off at any point woth no impact on the foil at design lift (CL=0.2), this gives a lot of freedom in terms of section structural properties since, if it is in the bubble, it does not damage performance.

This section only applies to the tip of the foil, the rest is out of the water at high speed and so the low speed bit can be a little more conventional as it is only in the water when it needs to be.

The 2D section L/D is 22. What this turns into when 3D is arguable for various reasons but I have estimated 12 for the geometry that I am using... time will tell although the models seem to support this.

Jon.

[Jon Howes]

I have attached three files. The first, "Basic Foil", is simply the output of my 2D design programme, this gives the pressure face and the zero pressure, bubble surface which continues into the wake, there is a pressure face bubble surface with a zero pressure differential also continuing from the trailing edge aft, this is not shown as it is a very boring, slowly curving line disappearing off to infinity! In reality it will close back in again but hydrostatic pressure, which drives this, is so low compared to dynamic pressure that it was not included in the calculation so the wake in this calculation shows a diverging bubble.

The second, "Practical foil", shows the trailing edge cut-off on the upper surface via a sharp chine. This would seem to be destructive of low speed performance, however, the amount of foil with this section is tiny (0.6 sq feet) and the foil above this has much greater area for low speed and acceleration, this low speed foil is lifted out of the water as the speed builds via a secondary planing surface just above the high speed section. The pitch control on the boat is used to trim the running angle of this planing surface.

The third file gives the coordinates of the practical version of the foil if anyone wants to play with it. Design lift coefficient is 0.2. The datum incidence as plotted gives this CL in 2D flow, obviously the 3D case suffers from downwash but this angular correction can be found by the usual, well known means from wing theory.

Jon.

[PI Design]

Thanks for sharing that Jon.

Attached below is a fascinating article by Paul Larsen (helm of SailRocket). It gives a real insight into what they are going through, and clearly describes the directional stabilty problems they have. Its well worth a read.
http://www.yachtsandyachting.com/news/?article=136223

[sigurd]

how does it stay inside the water? is there a hook shape, is it inclined, or is the arm that is holding it excerting aerodynamic downforce, or is the hull, hanging in air between the foil and the wing, pushing it down?

If all the boat leaves the water, will it glide properly back, and at what pitch angle is it then assumed to land?

[Jon Howes]

Sigurd,

1: It is inclined

2: The arm can generate downforce, upforce, or no force, depends on the needs of the course sailed.

3: Both foil and wing generate an upforce and the hull balances this with its weight.

4: If the entire boat leaves the water it is stable, both statically and dynamically, in all respects except for roll. A roll acceleration towards the wind occurs to ensure that the foil is the first element to make contact with the water. Pitch angle at landing is the choice of the operator, just like a stable aircraft.

Jon.

[Munter]

So Jon,
How is the boat coming along? Its been a long time since the web page was updated.

[Jon Howes]

Thanks for the enquiry, no bl**dy money at present so working on other projects to allow us to self-sponsor. I am buliding a larger model at present and going all out for speed with this one rather than just functionality since I would like to see at least how fast I can get a "sailing object" to go. This one uses a couple of small hydrofoils under the hull to get the hull out initially as it allows a better aerodynamic shape if not compromised by the need to plane before take-off. Will keep this forum posted as it moves on.

Jon.

[woodchuck]

What ever happened to the monofoil? Did it ever get built? I believe the trash in the Gulf would destroy anything at 100mph. I hear of boats punched at much less speed.
woodchuck

[Jon Howes]

"What ever happened to the monofoil? Did it ever get built? I believe the trash in the Gulf would destroy anything at 100mph. I hear of boats punched at much less speed.
woodchuck"

Read my previous post. Wing complete, all moulds complete, no money, building a new, larger model in frustration. I will finish this off when I can afford it.

Jon.