Author Topic: Unlimited board speed test and SIC Standamaran review  (Read 26068 times)

blueplanetsurf

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Unlimited board speed test and SIC Standamaran review
« on: July 24, 2011, 05:02:04 PM »
Last week Evan Leong and I had a chance to test Mark Raaphorst's S-16 Standamaran prototype that he was shipping to New York for a race with a stopover on Oahu.  I have been wanting to organize a speed test for SUP race boards for a while, so this was a good opportunity to comparison test unlimited boards in flatwater conditions.  Please check the spreadsheet for detailed results and watch the video for more information on the test.  Next up will be speed tests for 14' race boards and 12'6" race boards. 

http://zenwaterman.blogspot.com/2011/07/flatwater-speed-test-unlimited-sups.html
Robert Stehlik
Blue Planet Surf Shop, Honolulu
Hawaii's SUP HQ
http://www.blueplanetsurf.com

Takeo

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #1 on: July 25, 2011, 06:11:45 PM »
Interesting results, I expected the Standamaran to be a lot quicker than the other boards.  The Bullet isn't really a flatwater board, but I must admit, for such a proven downwind board, it's pretty decent in flatwater speed too. 

SUP_Dawg

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #2 on: July 25, 2011, 07:30:05 PM »
Great info. Thanks Robert.

Six Feet and Glassy

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #3 on: July 25, 2011, 11:07:49 PM »
Once again,  MAHALOZ for such a great service and education for us!  So interesting the cat didn't smoke all others.  Also interesting rankings of the other boards.  

Looking forward to hearing possible reasons for these results.

One question:  Do you have the weights of the boards?

Thanks again!
Ken

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #4 on: July 26, 2011, 07:17:15 AM »
Robert – I’m a scientist by trade, and find these types of comparisons fascinating. It’s absolutely marvellous that you have presented the actual numbers. I couldn’t help but have a quick run through the data you present on the spreadsheet. I haven’t had a chance to have a proper look yet, but I thought I’d let you know what a cursory glance shows.

This is a good set of data. Ignoring the issue of the standamaran, and considering only the single-hulled boards, you can explain over 90% of the times on each of the runs here by knowing the information given: who was paddling the board, the length and width of board, and which trial number the time came from.  That’s really excellent for data of this type – you must have conducted this evaluation pretty carefully. There’s a lot of care and work that has gone into this.

What’s particularly interesting in these data, beyond the simple issue of “which board is faster”, is to compare the relative importance of all these different factors like paddler, board width etc. upon speed.

In THIS data set, it breaks down roughly like this:

Run 1 or run 2: Over 85% of the time differences in these trials can be attributed to this factor alone (was one run upwind, and the other downwind, or were conditions changing, or were you just getting tired, or all three?).

Width of board: A further small percentage (between 1 and 5%) of the time differences could be explained by knowing the width of the board alone.

The other factors weren’t really particularly important determinants:

The three riders seem remarkably well matched in terms of ability, and there were no statistically significant differences between them. (This doesn’t mean there aren’t any differences at all, just that they are so slight that scientists wouldn’t generally count them as noteworthy.) A race between you three would be worth watching!

Board length also wasn’t important either. However, the boards are of roughly similar length, which might explain why this didn’t come through either as particularly important in determining speed. But it is nevertheless interesting to note that whilst there is a range of lengths between 17 and 18 feet, this factor seemed (at least in this dataset) to be only about as half as important in terms of determining speed as the relatively small width differences of up to 1.75”.

BUT before concluding that width is all-important, you need to note that width and length tend to be correlated – longer boards can be narrower because they afford greater stability. So it’s not always straightforward to decompose the different contributions. However, if going fast is your bag, it looks from this very limited set of data that you should be asking yourself “how narrow can I go?” rather than “how long can I go?”

There a just a couple of observations here I should check with you, though: Jared put in a time on the 18’ Bark in time 2 which was quite a bit slower than would be predicted. And your (Robert) time on the SIC Bullet on the second run was also a bit out of kilter with the rest of your times. Do you remember anything unusual happening on these two runs – stronger winds, wake, a paddle fumble or stumble?
It would be interesting to add information about price (i.e. to ask which board give the best value in terms of speed per $), and weight, to see how this compares with e.g. length and width as determinants of speed.

It would also be interesting to see how these influences, and the relative speeds of the board compare when you measure them over longer distances and different conditions. These are very different design boards (and price) so of course may be much better or worse in the conditions for which they were designed.

But thanks again for these data, I learned a lot.

(btw, I put a fixed fin in my Naish 17, and removed the rudder gear, and this has helped flat water speed considerably, largely because I can stand comfortably further forward, and use e.g. tracking fins. So if you are a Naish 17 owner who wants to use it for flat water, you might consider this simple mod – the performance might then be closer to the others on test here – and after all, according to Robert’s data, the (presumably standard) Naish 17 was only a fraction slower overall than a Bark 18”x26”, which seems to me remarkable for a good value production downwind-oriented model.)

PonoBill

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #5 on: July 26, 2011, 07:49:57 AM »
Very interesting comment Area. I thought roughly the same thing looking at the data and I've noticed the problem before in doing my own comparisons. It doesn't take much to skew the results. It would be a real PITA but I think the only way to get a useful test (by useful I mean indicative of actual speed differences) is a lot more runs.

I've played around with some drag testing using the handy moving water of the Hood River and a fish scale but I came to the conclusion that it's a very limited test. These are dynamic vessels, and there's a lot going on.

In a set comparison like this some paddlers get tired, some get warmed up, some are slowed by instabilities, some aren't. The balancing capabilities of people change dramatically over a few seconds--it seems our brains and muscles start integrating very quickly. That little scam test that people do to sell potions and charms of giving a little shove to unbalance you, giving you the potion or charm and then showing that you resist being unbalanced much better is just a balance LEARNING test. People get used to a particular board very quickly, but then have less confidence on one that feels different.

Adding more runs and then analyzing the data to factor out the influence of when the boards were paddled might give a more reliable result.

The difficulty of getting reliable performance data is why we shifted the old Ke Nalu board comparisons into a "showcase". we decided it wasn't possible to get meaningful comparative performance data except at the extremes--it's easy to detect horrible.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

Area 10

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #6 on: July 26, 2011, 08:45:08 AM »
 PonoBill, I agree 100% with your points.

But perhaps I wasn’t clear about the statistical methods I employed here – I thought my post was enough of a geek-fest as it was!

I used a method called multiple linear regression, which allows you to enter all the factors in together, and consider that various influences of each one, factoring out the influences of the others.

In the case of this comparison Robert was kind enough to provide enough data about the runs he did that I could “factor out”, albeit in a very crude way, things like changes in speed over runs due to tiredness and\or wind direction, and differences in performance between individual paddlers.

So the figures I quoted weren’t derived by e.g. adding up rows of columns in a Table and just dividing them to get a proportional difference. Instead I was building a statistical model to try to understand the interactions of the important factors and remove the influence of unimportant ones. So, as far as these data allow, I tried to do exactly what you recommend.

You are certainly right though - the data provided by Robert are absolutely minimal in terms of being able to use complex statistical procedures like these. Which is why I was being cautious in terms of the conclusions I was drawing.

There are many other caveats that I’d like to add – such as that the paddlers may have been more familiar with some boards than others, and we all know how that can affect performance. Ideally of course you’d be conducting a double-blind trial – that’s what most scientists would really like to see. But that isn’t actually physically possible for a SUP comparison without some huge ingenuity and investment.

But right at this moment, it looks to me that these data are saying that width is a more important determinant of theoretical speed than length in flat water. Hardly revolutionary, perhaps. But a natural question about this particular comparison is whether the board that seemed to be fastest was ONLY so because it was also the narrowest, or whether there really is something more subtle about the design that makes a difference. It does look like there might be (weight? Bow shape?) because it is a clear “winner”. But until someone can provide data from another board the same width, it will remain a possibility that actually, the things that contribute *most* to board speed are relatively simple – in flat water, perfect conditions anyway. Maybe even some design aspects currently being considered are red herrings, or just marketing flim-flam, or only help in very specific and rare situations. I doubt in many cases if the designers are entirely sure themselves at this early stage of the sport.

Robert’s data might be the beginning of the kind of thoughtful trials one would need to establish such things.

In entire agreement, I think, with you, I am in fact a firm believer that performance in perfect conditions doesn’t mean much very often. I paddle in typically choppy cross- and onshore coastal conditions, and often my fastest board in those conditions is my 12-6, not my 14 or 17, both of which are narrower as well as longer.

You are certainly going to get no argument at all out of me in saying (a) it is a deceptively hard thing to determine which is the “fastest board”, and (b) that to be certain of anything much you’d need a much more extensive dataset.

But, actually, I just hoped my coffee-break meander through the data might provoke a more thoughtful consideration of Robert’s data than just “the Ohana is the fastest board” – perhaps that was true on this day, and with these paddlers, but the more interesting things for me was to try to understand WHY that might be.

It’s certainly a damned nuisance for me if width is the most important factor in speed, because my balance is not that good!

PonoBill

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #7 on: July 26, 2011, 09:24:37 AM »
I assumed since you said first that you were a scientist that you were doing a multiple linear regression.  I would have assumed the same thing if you said you were a sleazy direct marketer like me. We use the same toys, but I used them to bullshit (did I say bullshit? I meant inform) clients.

I might have some data of another kind soon. I'm going to be using my Naish Glide as a test bed for various bow shapes. The Glide has extreme rocker and a flat, planing nose built for swell riding. I'm going to attach what I'm calling a Schnozz--a detachable bow. I plan to make a variety of bow shapes and test them. One width, one length, one paddler, multiple bows. Might get some useful information. I'm building the first "schnozz" today, though it's going to be for my Bullet. I want to see if I can improve the flatwater speed. Though it has less rocker than the glide it has a similarly planing bow, and pushes a lot of water in the flats.

I'm adapting my "paddle pod" data recorder to get lots of data--perhaps too much. It has a GPS and a two-axis accelerometer, I'm also making a water speed sensor with a small free-wheeling drag propeller on a shaft with magnets attached to trigger a hall effect sensor. The data recorder is really amazing, it includes two pressure ports that can be connected to pitot tubes. I have a pitot tube designed for water speed measurement, but I think it will not be sufficiently sensitive to serve as a water speed detector for this slow speed.

I think acceleration might be as interesting as speed.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

Area 10

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #8 on: July 26, 2011, 09:49:22 AM »
Wow - inside that "sleazy direct marketer" is a scientist trying to get out.

I'm interested that on the one hand you emphasise the difficulty of getting precise measurements (which is true), and yet still feel it worth going to such lengths to glean such fined-grained data. Is it possible that the error variance contributed by all the factors you can't measure precisely might overwhelm those that you can?

What are the questions you are trying to answer, or are you just enjoying the process?

It's certainly about time someone found a way to measure a board's stability...personally I'm more important in finding out what makes a board stable than what makes it fast, because I'm not fast if I'm in the water. I fell in four times during a race at the weekend...

Good luck to you, great to see someone attempting the appliance of science rather than relying on heresay.

refthimos

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #9 on: July 26, 2011, 10:09:54 AM »
(btw, I put a fixed fin in my Naish 17, and removed the rudder gear, and this has helped flat water speed considerably, largely because I can stand comfortably further forward, and use e.g. tracking fins. So if you are a Naish 17 owner who wants to use it for flat water, you might consider this simple mod – the performance might then be closer to the others on test here – and after all, according to Robert’s data, the (presumably standard) Naish 17 was only a fraction slower overall than a Bark 18”x26”, which seems to me remarkable for a good value production downwind-oriented model.)

Not to be a thread hijacker, but thanks for this little snippet of info.  I went from a 14' x 27" Rogue (square tail) to an 18.5' x 27.5" Bark (pin tail) and just have never felt like the Bark is as fast as I think it "should" be in flatwater.  I've suspected that one reason may be that I am developing bad habits by "riding the rudder" rather than controlling direction with paddle strokes, introducing unneccesary drag.  Just curious - on your Naish, did you find the rudder slowed you down even when you laid off it and let it run straight, or was it the trimming of the board with the rudder that was slowing you down?

I suppose this really isn't a complete thread hijack, because it sounds like the one variable that may not have been accounted for in the test was the effect of different fin/rudder combos.
« Last Edit: July 26, 2011, 10:19:00 AM by refthimos »

PonoBill

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #10 on: July 26, 2011, 11:10:52 AM »
Wow - inside that "sleazy direct marketer" is a scientist trying to get out.

I'm interested that on the one hand you emphasise the difficulty of getting precise measurements (which is true), and yet still feel it worth going to such lengths to glean such fined-grained data. Is it possible that the error variance contributed by all the factors you can't measure precisely might overwhelm those that you can?

What are the questions you are trying to answer, or are you just enjoying the process?

It's certainly about time someone found a way to measure a board's stability...personally I'm more important in finding out what makes a board stable than what makes it fast, because I'm not fast if I'm in the water. I fell in four times during a race at the weekend...

Good luck to you, great to see someone attempting the appliance of science rather than relying on heresay.

I have no idea. I started out trying to build a data recording system to see what is going on with paddles. So I've got this here hammer and I'm wandering around looking for nails. You're absolutely correct, I get a big wad of data that is hard to interpret but easy to see. Here's what I mean by that:



The picture says "crappy paddle" the data...no idea.

I'm going to stick all this stuff on the board because I've got it. Of course in the software I can look at each track in isolation. I don't think there's any analysis that will make quantifiable sense out of it. If I came up with one I'd stop screwing around and just go straight after the stock market.

When I was a kid I wanted to be a physicist. From about age four. But no one knew about ADD back then, so I was a "bad student" who barely got out of high school, but scored 792 SATs and won a National Merit Scholarship. Flunked physics in my senior year. Same year I won the National Science Fair...   ... in Physics.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

Tom

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #11 on: July 26, 2011, 11:48:19 AM »
Back in the 80's I was working with a windsurf designer trying to make a faster & quicker to plain boards. We'd shape a block of foam and not glass it. We'd then tow it behind a boat at specific speeds with an 180 lb sand bag sitting on it, and measure its drag with a fishing scale. We'd then change its rocker, rails, concave, etc, and repeat the tests.
We learned a lot, but mostly just had the 'basics' re-enforced. By basics I mean, flat and straight is faster than curvy; boxey rails are fastest; floaty boards are faster at lower speeds.

Area 10

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #12 on: July 26, 2011, 11:52:20 AM »
refthimos - I think with my Naish 17 there were a couple of issues. I am not an expert of DW boards, so others may wish to contribute.

But clearly the steering arm on many DW-oriented boards is located in such a position that you can get to it whilst in the position for planing. For me, on the Naish, even with the mechanism in the “fully forward” position, this meant that I had to stand well behind the handle, which is located obviously at the balance point, which is in turn quite a way back from the actual centre of the board length-wise. Otherwise, unless you have miniscule feet, you are kind of half-standing on the steering arm, which is no good at all for any distance.

So in flat water I was forced to stand further back from centre compared with, say, a flat water 14 ft race board.  At my weight (172 lbs) I found that the tail dragged less, and the bow seemed to pierce at little better in flat water, if I stood further forward than this “downwind” position. In addition, I found I could steer by paddling better if I was standing more around the centre of the board than behind it.

So I ditched the rudder mechanism entirely, got a standard FU 10.25” box fitted just in front of the rudder and just have the board set up as a fixed fin board. As a bonus, I’ve found that it is actually better downwind now than it was with the rudder: round where I live, we don’t get the kinds of open ocean swells here that you find in Hawaii, it’s short period, and often created by water running over a tidal current going in the opposite direction. In these circumstances I’ve found that you have to get extremely far forward and really shove the nose into the trough, and then get back really quickly. With the steering mechanism gone I can move more around the deck and make the most of weight position changes. I also think that in the extremely rippy, messy DW conditions we have, the relatively small standard Naish rudder just couldn’t cope, and used to “steer itself” sometimes.

Certainly there are still occasions when it would be nice to have the rudder, when e.g. paddling extreme cross-wind. But this is compensated quite a bit by being able to paddle standing further forward, and keeping the nose down a bit. So I miss it much less than I thought I would, and am mostly very glad it’s gone. In further incarnations, it would be nice to see Naish offer a fixed fin box option as standard, alongside a rudder.

And you are right, I found that with the rudder in place I tended to use it for steering, creating drag, rather than getting forward and just paddling.

Plus, now I can adapt my fin to the circumstances, which helps a lot, especially with e.g. reducing weed-catching, and tracking.

So, in short, I think my Naish is now faster in flat water, and decent conditons, because (a) I can stand at the balance point of the board, or slightly ahead if necessary, which improves the trim -at least at my weight and height; (b) because it is slightly lighter without the rudder gear; (c) it tracks better with a proper flat water race tracking fin; (d) I can use the paddle to change direction more effectively, rather than riding the rudder.

In this configuration particularly, the Naish 17 is an incredibly good all-rounder board, IMO.

Hope this helps.


JonathanC

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #13 on: July 26, 2011, 05:52:25 PM »
Hey Area 10, interested to hear that you installed the fin box in front of the existing fin - I would have just automatically put it behind!

I'm sure you thought it through, could you please jot down your thinking here? Obviously forward will make the board looser but I guess as you say you can compensate with a larger fin.

The SIC boards with the fixed fin box position the fixed fin behind the rudder, I had that on an F14 I owned but didn't ever get around to trying the fixed fin....

Thanks

finsider

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Re: Unlimited board speed test and SIC Standamaran review
« Reply #14 on: July 26, 2011, 06:12:32 PM »
Back in the 80's I was working with a windsurf designer trying to make a faster & quicker to plain boards. We'd shape a block of foam and not glass it. We'd then tow it behind a boat at specific speeds with an 180 lb sand bag sitting on it, and measure its drag with a fishing scale. We'd then change its rocker, rails, concave, etc, and repeat the tests.
We learned a lot, but mostly just had the 'basics' re-enforced. By basics I mean, flat and straight is faster than curvy; boxey rails are fastest; floaty boards are faster at lower speeds.

That sounds a lot like what Lindsay Lord did, except that book "Naval Architecture of Planing Hulls" came out in 1946. I need to find a new copy of that book, I had a pdf version on an old computer but lost it. Anyone have one? http://hydrodynamica.com/totem/lord-board

PonoBill and others. Awesome information. The engineer in me loves all the data, I like to know exactly why things are the way they are. Lately fins have been my scientific obsession. Anyway thanks to all of you for putting the time and effort into all of this, we know it isn't easy!
« Last Edit: July 26, 2011, 06:14:09 PM by SeargentFL »
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