The fun of unlimited boards

[PonoBill]

Nice post hefeweizen. I enjoyed it.

Photo, the answer to your question is long, I was trying to answer you simply, but I guess it wasn't clear. Let's try this. First of all, it's obvious that there is some length at which a board is too long for any person. A 100 foot long board would certainly have too much skin friction for even the strongest paddler to approach its hull speed of 13kts. So for every paddler there is some length where skin friction is the limit to speed.

For a non-peircing displacement hull the wave speed of an 18 foot board is about 6kts. For a 14 foot board it's 5kts. That's not a wall, it's the point where the resistance from the bow wave starts to rise exponentially. Any person capable of overcoming the skin resistance of an 18 foot board enough to get it moving above 5kts will go faster on the 18. If they can't overcome that much skin resistance and their speed is well below 5kts then the 14 will take less energy.

There isn't a lot of difference between theory and reality in this basic kind of hydrodynamics. Yes, there's some chaotic stuff that happens with poor designs, and there's small differences in skin friction between different hulls, but it's proportional and linear, and not huge.

As for your tests, there's a myriad of ways that on the water tests with groups of people and boards yield odd results. As carefully as something as apparently controllable as a drug trial is, there are times when the placebo is hard to beat.  It might piss you off to hear that your test is not scientific, or controlled in any fashion, or significant in any way--but it's not, it's not, and it's not.

Oh, and A10, I think those first two photos are of Salt Creek BOP. I did that race on a 17' Bullet with a rudder. Got one second and one first place finish--Sprint and distance. Of course the reason is that 1. I'm old and 2. There were only four unlimited boards in the race.  In that particular race I changed my entry from surfboard class, where I would have automatically won first place just by finishing--I would have been the only idiot over 60 on a 12'2" surfboard, to unlimited. I did so because the unlimited boards had a tremendous advantage: They started first. I didn't need to paddle through a littered battlefield.

[photofr]

@photofr
" I can paddle without fatigue for 6 hours straight using a UL board, "

Waow! You start feeling fatigue after how many hours?

"and still average a better speed than 30 minutes on a 12'6 race board ?"

X12 longer effort and more speed!

The harsh reality is that there are different ways of paddling. There are probably a number of ways to describe it, but I always like to portrait it and estimate it like this: 50% effort (tourist mode), 80% effort (efficient mode), and 95-100% effort (racing or serious training mode).

At 50%, the average paddler will average about 4 to 5 kph.
At 80%, the average speed is about 7.8 to 8.8 kph.
At 95-100%, the average speed is about 9.2 kph.

I can paddle at 80% and get into a rhythm that allows me to paddle for a very long time. I wake up the next morning, and even at my old age, I’ll discover zero muscle pain, and absolutely zero shoulder pain. The best part is that on an Unlimited board, I never feel like the board is “stalling” when paddling at 80% effort. I have paddled multiple days for 6 hours.

When I paddle at my 95-100%, I seem to max at in under 2 hours of paddling. I always wake up the next morning feeling intense muscle pain, and absurd shoulder pain.

I can only speak for myself, but I much prefer paddling super long distances at 80% - so perhaps that’s why I can last 6 hours in a race feeling totally like I could eat and go back out again.

[photofr]

@Pono:
Thanks for the explanation. I told you I understood the “theory” behind it, though you have made it even clearer. In fact, probably one of the best explanations I have seen in a long time.

It reminds me of a book I read that said that at a depth of 218 feet, humains would die while breathing straight air. Turns out that theory wasn't necessarily true.

Please note that there are two tests:
The one with the group of 5 people
My numerous mileage and extensive GPS data

For argument sake, let’s just throw the Group Test out the door – even though, interestingly enough: the woman paddler HATED the Ace GT 17’4 board… even came back saying “this board sucks, doesn’t glide, and feels like a tank” … even though she got her second best time on that board. But like I said, let’s just ignore all that data for a second.

Scientifically speaking, skin resistance is true. In practice (GPS data in hand) please tell me WHY the following happened to me:

My data (personal paddling for 1000s of kilometers) shows that my overall average speed ON LONG DISTANCE flat water paddling is always greater on either the 17’6 x 23 and/or 17’4 x 27 than any of the 12’6 boards I have ever tried?

Note: Long distance as in: anything over 1 km.

[PonoBill]

Because you are paddling at the most efficient point--a speed just below the large increase in resistance caused by wave friction. You are probably also taking short strokes, putting most of the effort into the first few inches of pull, and maintaining a relatively high cadence--all factors that make long boards comfortable and efficient close to their hull speed. You don't get the same kind of benefit from a shorter board.

As I said before, you don't gain much from trying to paddle much faster than your board is moving--it's inefficient. But a board being paddled goes through a cycle of speed--it accelerates while you are applying power, and decelerates when you recover. A longer board has a wider range of relatively linear resistance. It translates into a feeling people call glide, but it's really just that the board doesn't poke into the exponential increase in resistance caused by wave drag unless you really go at it hard.

[Area 10]

Photofr - I have two experienced male friends who has the exact same reaction to trying my UL board as your female friend. They said it felt like a tanker and they didn't feel in control, and it felt like canoeing to them rather than a board sport. They actually felt unsafe and nervous when the wind got up because they said they felt the board would just go where it wanted rather than where they wanted.

On pure flat water they were both surprisingly slow on it, with one in particular being quite a bit slower over a 3 mile circuit than on a 14ft Bark Dominator. He said that he just didn't feel he had the power to get it moving. We tried various different techniques and paddles for him on the UL board to get him to go faster but we just couldn't find any way to get him even moderately fast on it, despite the fact that I am much faster on the UL than on any 14, including the Dom.

Both paddlers are around the 147-158 lb mark.

I guess that UL boards are not for everyone. Speed isn't everything for everyone. Just because you feel happier on a UL doesn't mean everyone does.

I think the "it's not a Boardsport any more" comment is telling. If you have a background in kayaking, canoeing, surfski, OC etc then I think that UL SUPs feel quite natural to you. But if you come from a surf or windsurf background then UL boards feel alien and barge-like. Since most SUPers in Europe come from a windsurf/surf/kitesurf background, this may have contributed to the slow sales of UL boards.

[photofr]

What UL board did they try out?
Make
Model
Year

What is the weight of that board?
Did it have a rudder?

Regarding the two paddlers who were slower on flat water with that UL, do they have very narrow shoulders? Do they both happen to be very new to the sport of SUP?

The reason I am asking is because "factors" always make a difference. Details make it easier to understand.

[Area 10]

What UL board did they try out?
Make
Model
Year

What is the weight of that board?
Did it have a rudder?

Regarding the two paddlers who were slower on flat water with that UL, do they have very narrow shoulders? Do they both happen to be very new to the sport of SUP?

The reason I am asking is because "factors" always make a difference. Details make it easier to understand.

They tried my Naish Javelin 17ft carbon. I don't know the weight. It's not light but it's no heavier than many 14s.

Yes, we tried it both with the rudder and without.

They are both experienced SUPers. One was the UK champion racer in his age group at the time.

They aren't especially narrow-shouldered, although at their weights they aren't exactly The Rock. But this is a red herring since my UL is narrower than their Bark Dominators.

Some people just can't get big boards going. I'm not sure why. I think it's something to do with a cadence/power ratio. Both of them had trouble keeping the board tracking well, also. Which is odd because it tracks great for me.

I'm still a bit mystified. But it wasn't a minor thing. They absolutely hated the board - I had lent it to them to enable them to go faster for a particular training exercise we were doing but they ended up slower.

It's not just this particular UL either because I've seen the same thing with another UL board (actually, the older one that UKRiversurfers owns now). One guy who tried that was faster on a 12-6 Bark in flat water than on that 16.5ft UL board! I was a lot faster on the UL, and my friend who is bigger than me was about the same on both. Go figure!

Btw, a group of friends and I tried downbreezing on the Naish 17 and Naish 14 of the same year. Same construction, same shaper, same rocker. We were all faster on the 14. Once the wind gets up it's a different matter for some but not others, but in light winds the smaller board is faster for most people. (Actually, once the wind gets only 10 knots or so I'm faster on the 17, but let's not complicate things even further...).

So, although there are some general principles for these things, you don't have to look too hard to find examples that break them. I've seen many other examples (eg. young girls faster with big bladed paddles that most men struggle with, than small ones aimed at women). As my dad used to say: "those who generalise generally lie".

[UKRiverSurfers]

Perhaps when SUP matures as a sport, clubhouses will spring up at beaches and lakes everywhere, and then the UL class will start to grow. But that will only happen in Europe if it becomes a sport for the rich (like sailing and rowing), so it's swings and roundabouts.

I started sailing at my secondary school for 50p per season

Granted the boats were crap! But accessible to anybody.

Our rowing club is also open to anybody, not just the wealthy. A rowing scull is not too much either.

[UKRiverSurfers]

DW
Unlimited boards aren’t just about downwind. A 17-footer bullet will have more glide on flat water than most 12’6 board. However, speaking of DW, there are literally endless possibilities for DW on an Unlimited board on nearly any body of water from West Virginia to Florida, to Nevada and to Hawaii, without even talking about countries like France, Spain, Italy, the UK, etc… To say that there are few DW possibilities is like saying there isn’t a lot of water on this planet.

My Bullet is the fastest board in my fleet in all condition, flat, downwind, cross chop etc... Purely because of its length.

On the Thames its faster than my k15

[Area 10]

DW
Unlimited boards aren’t just about downwind. A 17-footer bullet will have more glide on flat water than most 12’6 board. However, speaking of DW, there are literally endless possibilities for DW on an Unlimited board on nearly any body of water from West Virginia to Florida, to Nevada and to Hawaii, without even talking about countries like France, Spain, Italy, the UK, etc… To say that there are few DW possibilities is like saying there isn’t a lot of water on this planet.

My Bullet is the fastest board in my fleet in all condition, flat, downwind, cross chop etc... Purely because of its length.

On the Thames its faster than my k15

Yes, I'm faster on my 17ft DW board in pure still flat water than on a K15 too. Except when going with a current, when the K15 is freakishly fast. 

[Area 10]

Perhaps when SUP matures as a sport, clubhouses will spring up at beaches and lakes everywhere, and then the UL class will start to grow. But that will only happen in Europe if it becomes a sport for the rich (like sailing and rowing), so it's swings and roundabouts.

I started sailing at my secondary school for 50p per season

Granted the boats were crap! But accessible to anybody.

Our rowing club is also open to anybody, not just the wealthy. A rowing scull is not too much either.

Perhaps I wasn't clear enough. My point was that it will have taken the patronage of some rich people over a long period of time to get to the stage where the big facilities of sports like sailing and rowing are accessible to paupers like me. SUP will need that too if we are ever to be on a par with eg. rowing in this country. I can't see it happening, though. But that's OK. I'm happy with doing something that is the runt of the paddlesports litter, because it is simply more fun

[photofr]

@ AREA10:
Yeah... your finding humans who do not go faster on a UL on flat water is very strange.

I have put more than 25 people on my two different UL (and they couldn't possibly be more different from one another). My findings (based GPS data) is that, with the exception of a single person (a top French racer) All testers were faster on BOTH boards in the flats. The top French racer was faster on the 23" wide UL on flats, slower on the 27" on flats, but noticeably faster on mega DW using the 27" board.

Like you said: it may just be a mystery as to why your testers didn't have faster times. Interesting though...

[UKRiverSurfers]

Photofr - I have two experienced male friends who has the exact same reaction to trying my UL board as your female friend. They said it felt like a tanker and they didn't feel in control, and it felt like canoeing to them rather than a board sport. They actually felt unsafe and nervous when the wind got up because they said they felt the board would just go where it wanted rather than where they wanted.

Who?

The 'pro' who said he could hardly stand after a 20 mile sea paddle 

[UKRiverSurfers]

The term 'weekend warrior' springs to mind lol 

[photofr]

Because you are paddling at the most efficient point--a speed just below the large increase in resistance caused by wave friction. You are probably also taking short strokes, putting most of the effort into the first few inches of pull, and maintaining a relatively high cadence--all factors that make long boards comfortable and efficient close to their hull speed. You don't get the same kind of benefit from a shorter board.

As I said before, you don't gain much from trying to paddle much faster than your board is moving--it's inefficient. But a board being paddled goes through a cycle of speed--it accelerates while you are applying power, and decelerates when you recover. A longer board has a wider range of relatively linear resistance. It translates into a feeling people call glide, but it's really just that the board doesn't poke into the exponential increase in resistance caused by wave drag unless you really go at it hard.

THANKS PONO
It's clear to me that we are on the same page. Somehow, I misunderstood you earlier. My apologies.
Thanks again for the explanation.