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    • Zapata

      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  
Doug Lord

Radio Control Multihulls

1,564 posts in this topic

 

 

 

 

 

The lifting surfaces placed on the central dagger board may lift the craft - but more importantly they diminish the Righting moment so heavily that the Lift to Drag ratios are doomed to poor performance.

A gem of absolute nonsense! The mainfoil begins to unload as soon as the boat takes off,reducing drag substantially. Then, the foil can create downforce which increases RM as required. At no time does the main foil reduce Righting Moment!

It's amazing how many people get so simple a concept so very wrong: when the boat takes off it speeds up, increasing the strength of the apparent wind which ,in turn, increases the pressure on the sail which, in turn, produces a heeling moment which,in turn, reduces the lift requirement from the main foil-that is, the increased heeling moment on the rig unloads the daggerboard lifting foil, reducing its induced drag.

The load is automatically transferred to the lee ama foil, increasing its efficiency.

Induced drag is, by far, the largest proportion of drag on the main foil of the Fire Arrow and it is reduced to zero as the wind picks up and the lift requirement from the main foil goes to zero.

Also, the horizontal lift for lateral resistance comes ,primarily, from the mostly vertical portion of lee ama UptiP foil which is set at +3 degrees angle of incidence relative to the center line of the boat. That means the vertical portion of the daggerboard is unloaded since the daggerboard is set at zero degrees.

Most 3 foil(in the water) foilers develop lots of induced drag on all three foils. The exceptions can be the wand controlled foilers like the Rave and Osprey and the Hobie Trifoiler with foil AOI controlled by "feelers". When those boats speed up they begin to unload the weather foil until it is completely unloaded as a precursor to beginning to develop downforce.

Doug, you write this like the boat actually sails on a regular basis. The REAL reason for the center foil is to make it easier to mount on a stand. Come on, that's why it's here, right?

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[quote name="Doug Lord" post="5031982"

 

A gem of absolute nonsense!

 

Induced drag is, by far, the largest proportion of drag on the main foil of the Fire Arrow and it is reduced to zero as the wind picks up and the lift requirement from the main foil goes to zero.

 

Dougie of all the dumb things you have said this is probably the worst. You don't really believe that the drag on your magIcaL foil goes to zero just because it's lilt goes to zero do you? A quick review of the coefficient of lift to angle of attack, and coefficient of drag to coefficient of lift charts for a foil proves otherwise. For arguments sake let's look at the charts for a naca 0012 foil, a commonly used symmetric. foil shape on beach cat foils. From Abbott and Von Doenhoffs "Theory of Wing Sections" page 462 the chart of Cl vs AoA we verify that at zero angle of attack the Cl is indeed zero, and from the Cd vs Cl chart on page 463 we see that at a Cl of zero the Cd is not zero it is 0.01. This may seem small but as a comparison at a 8 degree AoA the Cl is about 0.8 and the Cd is 0.018.

 

Which just goes to point out the probable likely hood that YOU DON'T KNOW WHAT YOU ARE TALKING ABOUT.

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Mr. Pee, I said induced drag(drag due to lift) goes to zero-that doesn't eliminate all drag from the foil going thru the water, but it eliminates the drag due to lift. You should read more carefully.




11c4nt3.png



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Doug, is there induced drag when it's sitting on the stand? Hell no! You could add even more mounting brackets, I mean foils, and not have to worry about drag...

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Too light over the 2 hours+ I was at the site. 3.7mph max on the Davis windmeter. Takes 5mph to foil at the earliest......Got some practice with the Trapeze Power Ballast System--and learned that sailing this thing and taking video are mutually exclusive. Too bad.

 

1zf0uo2.jpg

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Ever hear of a helmet cam? It's something kids use these days to take video while doing something. I would think someone of your tech savvy nature would have heard of those. Small enough you could mount to your boat...

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Too light over the 2 hours+ I was at the site. 3.7mph max on the Davis windmeter. Takes 5mph to foil at the earliest......Got some practice with the Trapeze Power Ballast System--and learned that sailing this thing and taking video are mutually exclusive. Too bad.

 

1zf0uo2.jpg

See, you can use the foils to mount the boat for photos! They have use!

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There you go doRdY - latch like a pitbull onto the facts that support your argument and completely disregard the facts that don't.

 

Are you a politician in another facet of your life?

 

Isn't it time to abandon these two train wrecks and divert your attention onto another more worthy design that will be even more radical, cutting edge and even more red than the last two?

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The lifting surfaces placed on the central dagger board may lift the craft - but more importantly they diminish the Righting moment so heavily that the Lift to Drag ratios are doomed to poor performance.

 

A gem of absolute nonsense! The mainfoil begins to unload as soon as the boat takes off,reducing drag substantially. Then, the foil can create downforce which increases RM as required.

It's amazing how many people get so simple a concept so very wrong: when the boat takes off it speeds up, increasing the strength of the apparent wind which ,in turn, increases the pressure on the sail which, in turn, produces a heeling moment which,in turn, reduces the lift requirement from the main foil-that is, the increased heeling moment on the rig unloads the daggerboard lifting foil, reducing its induced drag.

The load is automatically transferred to the lee ama foil, increasing its efficiency.

 

 

On the Fire Arrow, because it sails at a 10 to17 degree angle of heel, when the main foil develops downforce it also develops a component of lift to weather like what happens with Veal Heel, but differently. This helps prevent overloading the vertical portion of the lee ama foil in stronger wind. The daggerboard starts out unloaded due to the fact that the vertical portion of the lee ama foil is at a +3 degree angle of incidence and the daggerboard is at 0 degrees AOI.

post-30-0-43744800-1439835523_thumb.jpg

post-30-0-93796900-1439835729_thumb.jpg

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Doug - none of that actually occurs on the Fire Arrow.

 

You need the foil moving through the water. That never happens.

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My "crew" is gone for the rest of the year-looking for another.....Fire Arrow foiling one year ago:

 

 

28a7sqa.jpg

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crew needed for a remote controlled boat. Funny!

 

Who is it, Ant-Man?

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That's some powerful medication you are on doRdY.......

To claim:

On the Fire Arrow, because it sails at a 10 to17 degree angle of heel, when the main foil develops downforce it also develops a component of lift to weather like what happens with Veal Heel, but differently.

 

This is so ironic to be laughable; your past history of flaming the mothists with your claimed greater knowledge and then claiming that your downforce attempts are a type of veal heel. Are you a wind up spoof? The Frank Drebbin of Florida? The Mister Bean of Cocoa Beach or just Coco the Clown?

 

The microscopic vectoring to weather would be eradicated by the increased displacement drag, wetted surface drag, induced drag, wave making drag, viscous drag and all the other shit that is so fundamentally wrong with the stationary toilet seat.

 

You don't draw the supporting vector diagrams properly: but you show what you want to focus on AND you leave out the other forces that would be of far greater magnitude and in opposition.

 

None of your claims can be taken seriously - you have created a Stop, Start, Stop, drift, stop, drift, drip, drift, hip hop, lurchy lurch POS.

 

Now hurry up and refute everything with many more diagrams, claims and counter claims with some Red for good measure.......

 

Fact - your creations are boringly slow, with 14 secs of flight after 20 years of experimenting - when will you realise that you have taken a Cul-deSac for your route of discovery?

 

 

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That's some powerful medication you are on doRdY.......

 

To claim:

On the Fire Arrow, because it sails at a 10 to17 degree angle of heel, when the main foil develops downforce it also develops a component of lift to weather like what happens with Veal Heel, but differently.

 

 

The microscopic vectoring to weather would be eradicated by the increased displacement drag, wetted surface drag, induced drag, wave making drag, viscous drag and all the other shit that is so fundamentally wrong with the stationary toilet seat.

 

You don't draw the supporting vector diagrams properly: but you show what you want to focus on AND you leave out the other forces that would be of far greater magnitude and in opposition.

 

 

 

 

Ridiculous nonsense! You simply don't have a clue...........First you admit that there is "vectoring" to weather, then you use a silly term for a foiler(displacement drag), then you mention normal elements of drag for any foil. You don't mention that downforce as used on the Rave, Osprey, Hobie Trifoiler, and Long Shot and others has been proven for over thirty years! The gain because of downforce is greater than the loss from all forms of drag combined-an absolutely proven fact. And the gain to weather is unique to the Fire Arrow because of her angle of heel with downforce.

Your comments are no more than baseless drivel to cover something you just don't understand!

Rivals your post 1465 in the sheer inaccuracy of your words.........

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every time I see DL write in red i think of this

 

brick-loud-noises-b.jpg

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From the "you can't make this shit up" department, it seems that over on the toy boat forums where Dougie also posts, he claims based on his "testing" ( read " drifting") of his catamaran, he is modifying his foils and rig. Shocking! Even better he is asking for a volunteer to help him launch his boats sometime later in the year because his football coach assistant is gone and the weather is too hot. Again, shocked to think that this means Doug Lord has no friends! Perhaps we could organize an SA group trip to Florida to help him out and learn at the feet of the master. I'm sure a few of the current AC designers would love to learn the secret of the " bat foil"...

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From the "you can't make this shit up" department, it seems that over on the toy boat forums where Dougie also posts, he claims based on his "testing" ( read " drifting") of his catamaran, he is modifying his foils and rig. Shocking! Even better he is asking for a volunteer to help him launch his boats sometime later in the year because his football coach assistant is gone and the weather is too hot. Again, shocked to think that this means Doug Lord has no friends! Perhaps we could organize an SA group trip to Florida to help him out and learn at the feet of the master. I'm sure a few of the current AC designers would love to learn the secret of the " bat foil"...

 

 

Tom, we tried that. Back when he was a huge moth critic a mothy offered to fly him to the Gorge to see them in the flesh - and sail one.... He basically ignored the offer.

 

Just in the last 6 months I've offered to kick in some cash for a go pro so he wouldn't need a cameraman, and some of the more local guys volunteered to help him launch the boat, with the assumption that he's possibly disabled.

 

He ignored our offer.

 

He's a fairly deluded model boat maker. It's easier to just have him on ignore. Too bad he chases away good contributors. I would think that would get him banned.

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What a load of BS! Funny that a "huge Moth critic" like me has started and maintained the largest "Moth on Foils!" thread* on the internet! "You" offered to "kick in some cash"- now that's a joke-do you think that I would take anything you say seriously? Not a chance in hell.

"Some of the more local guys" offered to help launch-NEVER HAPPENED-that I know of. You don't give a damn about facts-you just make stuff up or quote other blank pages like yourself with zero cred. You're pathetic.

 

*361,000+ views http://www.boatdesign.net/forums/sailboats/moth-foils-35-9-knots-41-29-mph-11209-102.html

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Ok then, looks like someone else would like to help you out. Going to take him up on the offer?

Is there truth that you're changing the foils on the Cat?

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Foils have been adjusted on the cat to reduce low speed drag at takeoff while maintaining early takeoff. Rig reefed to allow a wider range of testing windspeed. Big rig has a max windspeed of around 5mph-7mph on foils.

 

http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-142.html

 

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you keep using this word "work" as in "this is how the foil works"

 

But yet, doesn't the foil need to be in the water, going a certain speed for it to "work"?

Since that never happens, all you have are word games.

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Speaking of word games: you saw the word "work" in my last post??!! Or was that just a hallucination? It's definitely concrete evidence that you frequently make stuff up to try to make a half-ass point.

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a "huge Moth critic" like me has started and maintained the largest "Moth on Foils!" thread* on the internet!

 

that right here is just sad

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Come on everybody.....Doug Lord needs a boat buddy....someone to share his love of stained, sweaty t-shirts, ratty beards, Internet trolling and not sailing....Won't anyone volunteer to be his new assistant? Please, this is your chance to give us all a full report on Doug's living and working conditions. I've got money on it that he still lives in his mom's basement....

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So the boat that hasn't yet flown - but has a concept that doRdY 'really thinks will work' - is having foil modifications. Ummmmm.....

 

When this lawn ornament finally lurches momentarily out of the water we will be regaled with stories of "I told you so" - "it flew on its first attempt - "my crusade has been vindicated" etc etc yada yada.......

 

(It also won't look as it did and will have been sailed 30-50 separate times)

 

Something other than his sweat stained T-shirt and Beard stinks here.................

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In thinking a little more about why Doug Lord can't find a single person to assist in his revolutionary efforts, I remembered a recent picture of his lordship and wondered if perhaps dougie's problem is olfactory. Which lead me to wonder what in fact Doug Lord actually smells like. At first I thought it was simply "ass". Now I'm thinking a combination of sweat, ben gay, and failure. Anyone else care to speculate?

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In thinking a little more about why Doug Lord can't find a single person to assist in his revolutionary efforts, I remembered a recent picture of his lordship and wondered if perhaps dougie's problem is olfactory. Which lead me to wonder what in fact Doug Lord actually smells like. At first I thought it was simply "ass". Now I'm thinking a combination of sweat, ben gay, and failure. Anyone else care to speculate?

This is just ugly.

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Ugly? Have you read Doug Lord's posts? His regular attacks? Do you realize how many years he has been trolling and fucking up sailing forums? How many people he has burned by sucking them into his delusions? Have you seen his pictures? After years of trying to be rational, I've come to the conclusion that the only way to deal with the a-hole is ridicule. And this is "Sailing Anarchy" last I checked....

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There are various syndromes available, many of them not yet named by medical science. Ultimately no one's to blame for the way they are, so the kind thing is to block anyone you can't stand. That's not so easy though if they have a habit of contributing useful stuff amongst a high tonnage of shite, and there's the real problem - the most irritating pests can sometimes provide posts which are essential reading, and that makes them much more infuriating than pests who only post shite.

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Ugly? Have you read Doug Lord's posts? His regular attacks? Do you realize how many years he has been trolling and fucking up sailing forums? How many people he has burned by sucking them into his delusions? Have you seen his pictures? After years of trying to be rational, I've come to the conclusion that the only way to deal with the a-hole is ridicule. And this is "Sailing Anarchy" last I checked....

 

the best way to deal with Doug, is to not deal with Doug. Go sailing. Have a drink. Do something else. Doug isn't changing because you dislike him. So you have to move on.

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FlyingHulls has had the A40 in production since September, and has announced its "Extreme Holiday Sale" with the basic kit at 30% off and All other bundles at 25% off. This means the basic kit is at $465.00 and the Ready-To-Sail bundle is at $995.00

 

Here is the FaceBook Page:

http://www.facebook.com/FlyingHulls-LLC-286941264706830/

 

Here is the web page:

http://flyinghulls.com/

 

And here is a recent photo of an A40:

BeachedA40.jpg

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The link mentioned above is to my prototype One Metre tri, which is here:

https://www.youtube.com/watch?v=5XeHFGvsAnw

We have now built the first production boat, which you can see foiling here:

https://www.youtube.com/watch?v=nzTf9pedWdE

 

We're pretty happy with it now, it can foil without any hands-on on the transmitter, and the kinked foils give the necessary bite when sailing to windward

 

post-52274-0-57473000-1455340872_thumb.jpg

post-52274-0-87607600-1455340999_thumb.jpg

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If Chris Durant of the Gosport Model Yach Club is on this forum, please email me at marketing@flyinghulls.com. Or, if any of you know him, please let him know I would like to correspond with him.

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Thats crazy- especially posting in an RC multihulls thread!! The best candidates for a Peoples Foiler are the Aeronamics 14( http://aeronamics.com/ ) and the Waszp( http://www.boatdesign.net/forums/sailboats/waszp-peoples-foiler-i-hope-52388-2.html ).........

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The link mentioned above is to my prototype One Metre tri, which is here:

 

https://www.youtube.com/watch?v=5XeHFGvsAnw

 

We have now built the first production boat, which you can see foiling here:

 

https://www.youtube.com/watch?v=nzTf9pedWdE

 

We're pretty happy with it now, it can foil without any hands-on on the transmitter, and the kinked foils give the necessary bite when sailing to windward

 

One Metre 2.JPG

Very cool. What is going on when it goes into the oscillations when going closer to the wind. It looks like it rises too far, the vertical portion of the foil comes out, and then the whole thing slides to leeward and falls?

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Congratulations Hydroptere.

 

Early days and practice on the sticks and you will achieve so much more.

Interesting to see how the boat flies on whichever foil becomes unloaded after sheet release; even at very low boat speed.

Also the boat seems to cycle through rapid lift off - too much leeway to maintain rig power - lurch to leeward, and foil sink.

Would this suggest trying a fraction less AOA on existing foils or Z foils to maintain leeway resistance as height rises?

 

Perth Mini Man - your thoughts????

 

Good Luck H

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Interesting to see how the boat flies on whichever foil becomes unloaded after sheet release; even at very low boat speed.

Also the boat seems to cycle through rapid lift off - too much leeway to maintain rig power - lurch to leeward, and foil sink.

Would this suggest trying a fraction less AOA on existing foils or Z foils to maintain leeway resistance as height rises?

Or maybe it just demonstrates that L-foils provide no pitch or heave stability.

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Yes, agreed - which is why Z foils have proved to be a good solution in A Class.

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This was a first test with firmly adjusted foil angles. In the future, the angle of attack of both foils will be automatically controlled and the stability will be improved. The aim is to give this boat of the Mini40 class good performences on up wind courses. <_<

A z-Foil works not well on up wind.

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This was a first test with firmly adjusted foil angles. In the future, the angle of attack of both foils will be automatically controlled and the stability will be improved. The aim is to give this boat of the Mini40 class good performences on up wind courses. <_<

A z-Foil works not well on up wind.

That sounds very interesting! Are you planning on using wands, or some other method?

 

Nice model, by the way.

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it will be controlled by a micro controller, servo and a sensor. 2 modes are provided. Automatic and manual operation switched by remote control ;)

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Can you please elaborate with more details, pictures and diagrams?

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Flevo Cup 2017

The biggest international RC-Multihull race in the world.

Place: Strandweg 1, 8256 RZ Biddinghuizen, Niederlande

 

post-51082-0-40197800-1492464226_thumb.jpg

 

The foiling RC-boat show!

 

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post-51082-0-94920500-1492465138_thumb.jpg

 

 

 

 

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Second biggest, no?

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Flying like an AC.....my new wing works well on foils ;)

 

DSC02137_klein.thumb.jpg.b0b116460e5527013e035ff8b9c5dd57.jpg21462252_768179843389523_566062833341525

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21371420_768179800056194_475566827792556

 

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That's awesome,  now if the guy with the tri would step up and also show us how well his model foils and sails, but I don't think he will.   :mellow:

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I have an exact scale foiling RC tri, Keith- and I'd be glad to show you some pictures-interestingly, there are now two fullsize tri's using the same basic system first invented by Fire Arrow:

MPX Fire Arrow-First Full Flying Foiling on video-7-24-14 009 (2).JPG

MPX_Fire_Arrow-First_Full_Flying_Foiling_on_video-7-24-14_011.JPG

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On 9/13/2017 at 7:24 AM, Hydroptere said:

Flying like an AC.....my new wing works well on foils ;)

 

DSC02137_klein.thumb.jpg.b0b116460e5527013e035ff8b9c5dd57.jpg21462252_768179843389523_566062833341525

 

 

 

Great work, Hydroptere-like the wing!

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Can you turn the prop mounting axis to simulate leeway?

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Do you collect any data from your tests?

Speed, at least, is easy to get since there are now small, light GPS units available.

Getting forces might be more difficult.

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51raFAi85BL.jpgIMG_28082017_082115_0_klein.thumb.jpg.4535651346e15096d7500a08ad821b22.jpg

Yes i do it .....   with a sony action cam

the cam recorded the GPS-data

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Most impressive!  What is the wrist watch type thing above?* The camera superimposes the GPS data from its own internal GPS? 

*Just looked it up: a remote view screen...

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12 minutes ago, Doug Lord said:

Most impressive!  What is the wrist watch type thing above?* The camera superimposes the GPS data from its own internal GPS? 

*Just looked it up: a remote view screen...

With the watch, you can start the camera and stop. You can also control the image on a display. The data is recorded as a text file and a video software are individually visualized the data with the video. Video software is called DashWare

DashWare

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Looks fantastic. The crossbeams seem to not add to stiffness at all. Won't that allow the platform to twist, making it very difficult to control foil AoA?

Also, why only one rudder? Is that for simplicity? I'd have thought that dual rudders would provide more stability and better tuning.

Upwind foiling tends to load up the leeward foil a lot, maybe talk to the A Class guys on what they're doing. They seem to have upwind Zs going very well. I suspect part of it is toe–in of the foils so leeway automatically causes proportionally more lift on the leeward foil and less on windward without continuous adjustment (though setup is likely very important).

Lastly, have you published any details of your design (wing, hulls, foils)?

 

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