Moth on Foils: 30.31 knots (34.86 mph)

[mdcf]

Originally Posted by Doug Lord

=======================
The xtra RM comes from the distance the center of lift of the foil is from the CG of the boat(horizontally). Compare a Moth sailed upright with the crew fully hiking to a drawing of the same boat with the crew fully hiking but heeled to weather 20 degrees. Altitude has virtually no effect on RM.
Also see this and the picture in 11 pages:

so the pivot point remains constant which gives you a longer righting arm, basically you get the boat weight and a small increase in arm length. Neither of which is insignificant in such a light boat. If I'm reading this right, you'd get a similar effect in a traditional hull where the freeboard was the same height as the vertical foil length and the vertical shape of the hull was concave if you were able to heal to windward (this would suck for other reasons.) So nothing intrinsic with foils, just you have the limit condition for a concave hull shape.

Have any comparisons been performed foiled moth vs. windsurfer with the same sail area? It would be interesting to compare as the records would seem to indicate that the foil boat is not as efficient.

[Doug Lord]

I don't think veal heel would ever be beneficial on anything but a foiler-and a bi-foiler at that. It could work on a bi-foiler with small "power foils" designed to increase RM but not on a monohull that is a seahugger as best I can tell.
There is an excellent comparison of windsurfer to Moth done by AMAC on the Bladerider site a couple of years ago. I'll try to find it later. One thing for sure: a Moth will foil before a windsurfer will plane and-so far- a windsurfer has a better topend speed.

[mdcf]

Originally Posted by Doug Lord

One thing for sure: a Moth will foil before a windsurfer will plane and-so far- a windsurfer has a better topend speed.

Do you mean, will foil at a lower wind speed than a windsurfer will plane? Above a certain wind speed (probably 10knots, based on the star-board site) it would seem that the foil craft is slower and gains no advantage by early foiling?

I suspect that foiling is a real blast, but it does seem awefully complex compared to the other options. As a complex technical challege it does have a lot of appeal though.

[Doug Lord]

Here is Technologika's Blog-he just put up an article about wands-inspired by some poster on SA(!). Great to see a little inspiration go a long way-read it and listen to the radio show: http://www.teknologika.com/mothblog/


News Flash: new hydrofoil book with a Moth design section: "Hydrofoils Design Build Fly" by Ray Vellinga Amazon. About 25US. Best book on hydrofoils in years!

[Doug Lord]

Originally Posted by mdcf

Do you mean, will foil at a lower wind speed than a windsurfer will plane? Above a certain wind speed (probably 10knots, based on the star-board site) it would seem that the foil craft is slower and gains no advantage by early foiling?

I suspect that foiling is a real blast, but it does seem awefully complex compared to the other options. As a complex technical challege it does have a lot of appeal though.

---------------------------
Here's AMAC's comparison -Bladerider vs. Formula: http://www.kasail.com/windsurfing/news/12june07.html

I think that a Moth with 90 sq.ft. would foil in a 5 knot wind-AMAC(Andrew McDougal-KA sail and MachII)said as much a while back-and do 2-2.5+ windspeed. I think for the best interests of foiling new "Peoples Foiler" wannabes will have to foil in light air. A lot of the windsurfers around here won't go out unless its 15k-so a light air foiler could be flying while most of these people are sitting around. A Moth will "normally" take off in 6-8 knots windspeed depending on crew weight and who you talk to.

[bistros]

Originally Posted by Doug Lord

I think for the best interests of foiling new "Peoples Foiler" wannabes will have to foil in light air.

Are you not part of this wannabe group you are dissing?

Originally Posted by Doug Lord

A lot of the windsurfers around here won't go out unless its 15k-so a light air foiler could be flying while most of these people are sitting around.

Sitting around? Isn't that what both you and I are doing right now? How many times did you get out and foil this year? Once? Zero? Have you been in a sail boat in the last decade?

Originally Posted by Doug Lord

A Moth will "normally" take off in 6-8 knots windspeed depending on crew weight and who you talk to.

It doesn't depend on who you talk to in the slightest, it depends on who is doing it, boat setup, conditions and the weight they are asking the foils to lift. Talk is cheap, and assembling statistics based on Internet claims is pointless.

--
Bill

[Doug Lord]

Originally Posted by bistros

Are you not part of this wannabe group you are dissing?
Bill

==================

I'm certainly not dissing any group most especially "Peoples Foiler Wanabes"-the future of hydrofoil sailing!

[teknologika]

Originally Posted by Doug Lord

Here is Technologika's Blog-he just put up an article about wands-inspired by some poster on SA(!). Great to see a little inspiration go a long way-read it and listen to the radio show: http://www.teknologika.com/mothblog/

What a load of BS ... that article has been around for a while, just not in public circulation. Doug you have NO idea what inspires me, and it is certainly not some poster on SA.

[Doug Lord]

Originally Posted by teknologika

What a load of BS ... that article has been around for a while, just not in public circulation. Doug you have NO idea what inspires me, and it is certainly not some poster on SA.

-----------------------
Really? This is a direct quote: "with a recent post over on Sailing Anarchy complaining that people never put information out there I rolled up my sleeves and wrote Magic wands – Wand control systems on Hydrofoil moths."

[teknologika]

Oh yeah I did say that. I forgot, 'cause I was too busy out sailing.

[bgulari]

shoo shoo doug go away and build something. Dont you wanna win a bet?
I thought i bet you that you would not have anything that you could sail in a year.

[ancient kayaker]

Originally Posted by bgulari

shoo shoo doug go away and build something. Dont you wanna win a bet?
I thought i bet you that you would not have anything that you could sail in a year.

Don't see why he should go away: he started this thread after all.

[bistros]

Originally Posted by ancient kayaker

Don't see why he should go away: he started this thread after all.

Well Terry, the story is a little more complicated than who started the thread. Bgulari is the current World Champion of the Moth Class (Bora Gulari) and an accredited Aeronautical Engineer. Doug has been provoking him, calling him out and generally being Doug Lord for quite some time.

Doug restarted the dead discussion of his Trapwing concept along with resurrecting another topic previously discussed to death on Sailing Anarchy. Unlike the good gentlemen here who have studiously ignored Doug attempts to re-ignite the Trapwing flames (new thread and ten posts - all by Doug), on Sailing Anarchy it spawned another endless Doug Lord shitfight. Doug is like an intentional car crash on the 401 - he can bring the whole forum to a standstill and ruin everyone else's reasons for being there. Like a car crash, those uninvolved think that if everyone ignored him and didn't rubberneck there would be no problem. In reality, if one person slows to take a look the whole forum is negatively affected.

It is amazing that the absolute best foiler on the planet is so tired of Doug that he's got time to try to reduce Doug's influence here. The sad thing for all of us is that we will never have the opportunity to learn from Bora and advance our discussions on foiling technology because of Doug's bad behavior. Just because Doug starts threads is no reason to support him - if he truly wanted to advance foiling through discussion of those experienced with foiling he'd just shut up and let them talk.

--
Bill

[ancient kayaker]

Bistros: I checked out "bgulari" so I already knew who Bora is and I respect his achievements. I have also checked out sailing anarchy, and I know some folk don't like Doug. Doug's behavior may have been less than ideal in other Internet locations, but not, as far as I know, on this forum. So I for one think it is inapropriate to raise such issues here.

Doug has been a useful source of information to me. Not all of us are involved with pushing the limits in foiling or other sailing technology but some of us like to be kept in touch. Doug does that for me and I am sure, for others too. Some of us appreciate his efforts and would not like to see him pushed out of the forum (again) because there is nobody else who seems to be trying to disseminate foiling information.

There is nothing to stop Bora starting his own thread here, I would like that very much, you too for that matter. I would regard either of those as positive developments: trying to supress the most prolific source of data is negative.

[bistros]

Originally Posted by ancient kayaker

Bistros: I checked out "bgulari" so I already Doug has been a useful source of information to me. Not all of us are involved with pushing the limits in foiling or other sailing technology but some of us like to be kept in touch. Doug does that for me and I am sure, for others too. Some of us appreciate his efforts and would not like to see him pushed out of the forum (again) because there is nobody else who seems to be trying to disseminate foiling information.

This is more or less a chicken versus egg type debate. Doug does disseminate a huge volume of information - with very questionable objectivity. The problem is that most folks that actually foil, build and design real full size boats are so tired of Doug that they now refuse to participate in forum discussions with Doug. Blessing and curse in one package.

It's a tough call - is the huge repetitive volume of Doug-centric anecdotally collected third party information more valuable, or would we all benefit more from hearing directly from the source? Personally, I prefer to develop my own opinions from raw data than to accept what appears to be biased conclusions form someone else. If Doug presented the bad and the mediocre as often as he does the positive, I'd feel better. I guess Doug's version of things seems far more "Fox News" to me than "BBC World".

You may be a better man than I if you can discern needles of wisdom from the haystack volume of overblown hype presented by Doug. I can state without doubt that Doug's presence here results in less (to no) participation by people who actually design, build and sail foilers in real life. Doug has presented no substantive evidence that he actually sails, designs or builds anything functional larger than a RC toy in the last five years.

<ducking from the incipient response from Cocoa Beach>

Cheers,

--
Bill in Ottawa