Moth on Foils: 35.9 knots(41.29 mph)

Discussion in 'Sailboats' started by Doug Lord, Apr 11, 2006.

  1. Stephen Ditmore
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    Stephen Ditmore Senior Member

  2. Chris Ostlind

    Chris Ostlind Previous Member

    John Travolta just ordered a foiling Moth

    From the Dougster: " And , 2, now monohulls ARE faster than catamarans - at least in boats under 20'...."

    Again, This means what, specifically, in the grand scheme of things that float?

    Let's see... foiler fever, canting keels, tricked out rigs, extravagant claims, sliding seats, more claims, work done by other guys, etc, etc. In the automotive world there's a name for the vehicle on which the designer has piled every possible option so that the marketing claims can exceed the bounds of good sense... Its called the Cadillac Escalade.

    I can't wait for the next technical lollypop to show-up so that our esteemed Mr. Lord has to decide for which specific muse he will dance. That will be an interesting dilemma.
  3. RHough
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    RHough Retro Dude

    Mono = One

    Bi = Two

    One hull = Monohull

    Two hulls = Bi-hull

    Calling the Moth a Mono-foiler is like calling a Schwinn a Uni-Cycle.

    The Moth class allows boats to race that are supported by more than one foil, how is that different than allowing boats supported by more than one hull?
  4. sigurd
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    sigurd Pompuous Pangolin

    I always found it interesting to know which boats were faster in what condition.

    Windsurfing is a good way to be introduced to sailing. Optis too, but they get a bit dull when you have driven them down a number of times. The same with big sailboards in much wind. I believe I started learning both at approx the same time, age 5. For pure racing however, I don't think most people care how fast the boat type is, as long as the others have exactly the same boat. I have been told by a parent that some are trying to replace the opti with something called a zoom. A bit larger SA so it won't be outgrown as fast I am told.

    Unicycles have no stability except in heave. I seem to remember a sailboard with a single T-foil.
  5. boogie
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    boogie Member

    the BS stops, when the data drops...

    hi guys,

    i suggest we put an end to the "my boat is faster than your boat" bantering.

    how about a represenative of each class that has any claims here sends me a GPS track and i'll analyse the track for max speed, averaged speed over distances, VMG over distance and so on. has an excellent free tool for doing so and i have analysed many yacht, windsurfing and kitesurfing tracks before.
    for best results try to record the tracklog in 2sec intervals. this setting seems to be the best compromise between track resolution, accuracy and track log capacity. it give you about 5.5 hours of track recording on a Garmin GEKO201 or Foretrex101/201. tracks recorded on the "auto" setting lose a lot of datapoints, as do tracks that are saved on the unit.

    lets even set a range of wind speeds that all can sail in. like 10 to 25kn as a guide line.

    send your tracks [preferably, but not necessary in .gpx format] to:
    kitespeed [at] gmail [dot] com

    the bulsh!t stops, when the data drops. :p

  6. Doug Lord

    Doug Lord Guest

    GPS tracks

    Boogie,do you have any experience with the Velocitec-that's what most of the Moth guys use?
  7. boogie
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    boogie Member

    no i don't. as far as i know you can't download the track from the unit and do a detailed analysis of the data later on. handheld GPS units are not 100% accurate, but by analysing the data, spikes and glitches in the recording are quite easy to spot on a track log.

  8. Doug Lord

    Doug Lord Guest

    Moth on Foils²

    A news flash: John Ilett just shipped the foils mentioned in the article in MOTHBALLS that are going on an Aussie 18. Now thats going to be interesting. Our own baronvonwhatever has posted a pix of an 18 on surface piercing foils with no accompaning comment(that I can remember) on the boatdesign forum. John's Fastacraft set will have MUCH LESS drag than those. The question is : we know that as a leadbelly gets bigger it's likely to have a higher top speed but is that true of a foiler? Will the Ayedeen really be a Moth²? Some otherwise knowledgeable people have said that only a Moth monofoiler can foil(or foil upwind) but we know that a 470(surface piercing -three foils), FD(surface piercing-three foils), RS 600( bi-foiler) and the 26(?) foot Monitor in the 50's have already foiled. The Monitor way back then with three ladder foils could tack while foilborne and sailed well upwind. We know that David Luggs 114 sailed well upwind on foils. So I guess the real question is will an 18 sail better with foils?
    My take on it: as pointed out numerous times one of the really cool things about the Moth is early takeoff; for instance KA claim their Bladerider with the big main will take off in a 5 knot wind and do 14 knots--waaay before a windsurfer will plane. So I'm thinking that the biggest gains on the 18 may be made in the relatively low windspeeds.
    I guess we'll find out before too long....
    Boogie, don't know whether you've seen it or not but on Rohan Veals website there are some comments by the designer of the Velocitec regarding the speed Rohan just posted in the Moth class contest; there is also a thread on SA about the thing...
  9. boogie
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    boogie Member

    Doug, you are not quite up to date on windsurfer technology, are you?

    Formula Windsurfing is a short board class without a centreboard and they mainly do windward leeward racing. they have a wind minimum of 7 knots for racing. a good FW sailor can get his kit [1m wide board/70cm fin/12m sail] up and plaining in 5-6kn with a good pumping technique and then maintain planing at around 13-15kn board speed across the wind. not much upwind-downwind in those marginal conditions, but you are fully powered from 8-10kn of wind speed for very good upwind and downwind VMG's.

    which brings me to another point. anecdotal evidence along the lines of "moth's are faster than windsurfers because Rohan beat a local sailor when he was sailing out on the bay..."
    how about lining up world champions against world champions? my guess is the local guy would have been lapped, by the WC of his class...
    i have added a picture of a recorded GPS track. the rider is a ex WC in the class the recording is from an actual race in melbourne/elwood sailing club at the oceanic champs a couple of years back in very choppy conditions with a SWer of 20-25kn.

    i am well aware of the Velocitek GPS unit. but last time i looked you couldn't download the data from the unit. it's a nice tool, but not what i'm after.
    i'm quite closely involved with the guys that run
    GPS-speedsurfing has around 600 registered members now in their ranking.
    there is a system of regional and global timekeepers in place that validates the submitted tracks. without the tracklog there is just no way to control claims of speeds done by the riders.
    tracks have been cross checked over and over again with timed video equipment and the speeds are within tenths of a knot of the "official" times as long as the distance is large enough. that is the reason why the main ranking is not the display read out or 1 second peak, but the average of the 5 fastest 10second runs.

    if they could add download functionality to the Velocitek i'll surely consider it.
    would be great if it could be done wireless [bluetooth] to avoid corrosion.
    there is just soooo much more information available if you can analyse the track after sailing. i'll see if i can put some samples together and post a few screenshots.


    Attached Files:

  10. Doug Lord

    Doug Lord Guest

    windsurfer GPS

    Boogie, I don't know as much about windsurfers as you appear to but I do know but the Bladerider probably wouldn't require pumping to achieve takeoff in 5 knts. I know that Rohan has lined up against Formula boards and been faster in some conditions but I don't know the details. From what I understand in many cases particulary the 49'er - to set the Austalian rating- he lined up against the best sailors in Australia.
    Similar story in his A class racing.
    It seems too bad that the Velocitec doesn't have the tracking capability you mention- I think I'll write and ask them about that. Would be really usefull. Based on what the designer of the unit has said on SA the thing is significantly more accurate as a speedometer than most other GPS units but I'm not sure why-maybe the 12 channels?
    Windsurfing --Boogie, I live near Tinho Dornellas' windsurfing school and am there both days every weekend and have been for over 5 years. I have a Davis windmeter that I keep with me at all times. A 'normal" weekend day with wind will draw up to 30 or so boards; I've seen many, many different boards including a homebuilt version of Rush Randle's(air chair) foilboard. I have never, in all that time, had the pleasure of seeing ANY windsurfer planing in 5 knots of wind no matter what they did. I'll ask Tinho about it this weekend........
    Last edited by a moderator: Jun 29, 2006
  11. Doug Lord

    Doug Lord Guest

    Ct 249

    One of the comments you made was in regard to a reference I made to certain "otherwise knowledgeable people" regarding whether or not the Moth is the only monofoiler that can foil. I was referring to Phil Stevensons comments on the Moth forum as well as to some internet posters who don't use their names(apparently) that seem to agree with Phils statements that only the Moth can foil and then that only a Moth can foil upwind. While I have great respect for Phil and what he has done he is just plain wrong in making those statements: David Lugg foiled a two person I14 upwind in 1999; the 1950's era Monitor(though not a bi foiler) foiled upwind and even tacked on foils. I'm 100% satisfied that if the I14 had not banned full flying
    hydrofoils that class would have made similar startling progress as has the Moth class.
    And others besides myself believe in the potential of larger monofoilers( keelboats on foils) including the Out 95 group and Sean Langman.
    For Rohans comments on the A class and 49er go here:
    and here earlier in the series:
  12. usa2
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    usa2 Senior Member

    Okay, so if the thing we are promoting here is top speed in boats under 20', the A-class is still faster than the Moth. So are F-18's. (does the A-Class fit into the F-18 rule?). So its still an irrelevant figure. Unless someone would like to point out why the consumers should care. An F18 cat can be had for $12,000 USD. And how much is a Moth?
  13. boogie
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    boogie Member

    do you have any hard data for A-Class or F-18 speeds?
    or is this statement based on anecdotal evidence too?

  14. boogie
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    boogie Member

    say hi to Tinho from me [Boogie @ C3] and make sure you ask the right question. :D
    something like: "what is the lowest wind speed that you have ever seen any of the top pro guys at the midwinters plane in across the wind?"


  15. Chris Ostlind

    Chris Ostlind Previous Member


    Lemme see... who was it, some page or so back, who was complaining about the thread being hijacked? Hmmm ???

    Now, the topic has shifted to planing windsurfers and data recognition via downloadable GPS systems.

    My, oh my, how the worm has turned.

    A very funny and ultimately ironic conclusion to another tale by the esteemed one.

    Thanks for the laughs, Doug.
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