New Racing Canoe

[sabsfeigler]

Yes that is clear, but if the maximum beam had been further back, the boat would have been that much easier to paddle.

in the newer boats the maximum beam is in a different place, resulting in a wider lwl at different places along the hull, the question is, how much would the added buoyancy being closer to the midship or towards the aft help with the pitching of the boat when paddling.

 

[tlouth7]

I think the beam was as far back as the designer could manage without affecting the submerged profile. If you look at the upturned photo you can see that the underwater shape is largely unaffected. This limit here is a result of the "no concave sections" rule.

Resistance to pitching comes from: fullness in the waterplane (specifically second moment of area about the pitch axis) and flare at the bow and stern. The gunwale planform does not directly affect these unless the deck is being submerged at the extremes of pitch. NB fullness in the waterplane will have a drag penalty due to increased entry angle and associated wave drag.

The minimum pitching design would be a very shallow skimming dish, basically a surfboard shape.

 

[sabsfeigler]

Well the lines plan shows the fullest part of the waterline to be almost in front of the paddler, but if you watch old races they were sinking these boats just as much as the modern ones. In which case due to heave and pitch the waterline near the beam is growing and creating a significant amount of reserve buoyancy compared to what is available in modern designs. Allowing for more of a shallow dish shape compared to modern boats.

I admit to my ignorance on the topic but I just don’t understand how moving the apex of the waterline aft wouldn’t help to reduce pitching.

 

[BlueBell]

Isn't pitching and heaving more a paddler skill variable?
Sure, the design is going to effect it but not in a good way if it slows the hull down.
I think the proof will be in the pudding.

 

[sabsfeigler]

Well if you watch a race, you can see that there’s not much to do to avoid heaving and pitching at race pace. The goal in canoe technique is to put as much weight on your paddle as possible during a stroke, but at the end of the stoke the weight must go back into the boat, this causes the heave. Reaching forward places more weight on the front foot pushing the bow down, during the stroke itself the boat rights itself and then especially the last half, when most of the athlete’s weight is back in the boat, it surges forward and pitches.

While the goal is to reduce the heaving, the reality is that it is much more tiring, and in the end slower to paddle with perfect technique in a race. They’re more concerned with pulling as hard as they can.

Old videos from the 80s-90s, you can also see the athletes aren’t using their lower bodies to move the boat. Imagine a golfer or soccer player strike a ball without hip drive.

This may make the boat run smoother, but the times show that it wasn’t efficient.

From a boat design perspective, I think it’s most important to not have the athlete need to reinvent how they paddle, but rather try to make a boat that performs no matter how they paddle.

 

[Kayakmarathon]

The canoe stroke involves shifting body weight, which causes the canoe to pitch. Pitching can get so violent that the bow submerges. An inverted bow will keep the canoe submerged longer. In a kayak, however, there is less pitching because the paddler rotates. Kayaks benefit from an inverted bow.

 

[gonzo]

The beauty of a racing canoe, or a racing anything, is that the best design wins races. That narrows the debate to a very small scope of designs. For example, after a catamaran won the America's Cup, monohulls became obsolete and no-one designed them to enter as a competitor.

 

[jakeeeef]

As someone who raced single sculls for many years and have rowed many different sliding seat rowing boats, I have to comment on the Nelo video.
Sliding seat racing sculls have changed very little re length, width, hull profile since the 1890s. To say they are a highly evolved design would be understatement.
Many manufacturers over the years have deviated from the tried and tested (lowest theoretical wetted surface area) U shaped hull profile built appropriately long and slender to adhere to the rules and mechanics of the rowing stroke. And often they have flattened the hull bottom a bit near the centre of the hull (although this one leaves the hull near the centre U shaped and flattens the hull bottom at bow and stern.
Flat sections near the centre of the hull do make a boat noticeably slightly easier to 'sit' ie., more stability, making novice rowers often faster simply because they get to keep their blades from striking the water a bit better on the recovery. Not sure what completely submerged flat sections at bow and stern on a displacement boat with very little rocker would do, if anything.
Going for marketing driven/ design differentiated designs like Nelo has here is a viable strategy for a newcomer brand in a sport like rowing, but an uphill struggle. The thing is, squaring off the U shaped underwater profile or similar relatively small tweaks will not noticeably detrimentally affect the performance but they will make it look noticeably different and draw comment. But in a sport where athlete genetics and skill are 99% of the performance the better athlete will basically always win, within reason regardless of boat.
So in the 1990s everyone fast was racing Empacher sculls (probably initially because they were the Olympic pool boats for a period and US colleges started to think they made fast VIIIs at one point for some reason- so better athletes started getting their ( yellow with black ends ) Empacher singles, they were seen winning more races, so people thought they were faster boats.), then there was a brief excitement/ flirtation with US manufacturer Fluid Design, who had the marketing story of the first 'CFD designed' single scull, or 'shell' if we're talking American. Same thing, a handful of faster athletes got them and won some big races. Then, from about 2005 an Italian builder, Fillipi started to be the Go-to boat, can't remember why that one ignited now, but you then started to see a lot of them in Olympic finals, then shortly after every rich guy at your rowing club had one. Didn't make them any faster though...

So, because the Nelo is going to have a speed potential within 0.5% of any other reasonably recent boat out there ( whether it's 0.5% faster or slower is actually a moot point), all that actually matters is that they get them in the hands of a critical mass of very fast (like Olympic finals fast) single scullers, and then the world will consider them a fast boat. Actually measuring, objectively, the potential speed difference between this new Nelo, or a Fillipi, or an Empacher, or a Chinese boat brazenly moulded straight off an Empacher (no registration of designs or IP of any kind allowed in Olympic class rowing equipment!), is impossible. Or rather they are all so close to each other to be unmeasurable. Squaring off slightly a displacement hull well underwater will slightly increase its wetted surface area, but so little it would be unnoticeable. The psychology though of an athlete that thinks it is faster, especially if the competition also fears it is faster than their boats- now that is potentially hugely significant.

Having said all that, I do like what Nelo have been doing. I also paddle race SUPs and follow development there, and Nelo launched a hollow, ie not foam filled carbon SUP, which was a first, made sense and something I was wondering when someone would finally do it. Unfortunately, in similar scenario to single sculls described above Starboard have all the fastest male and female SUP racers on their kit, so even if the Nelo board was, say 5% faster, nobody would actually ever find out! SUP isn't an Olympic sport so the range in speed between the people at the front of the fleet compared with the people even 10 places back is other worldly. Catch 22 for new entrants like Nelo, unless they can catch athletes that are unsponsored, very up and coming, and hugely gifted.

But I love it that Nelo are trying this stuff.

 

[TANSL]

monohulls became obsolete and no-one designed them to enter as a competitor.

That is very true but, if we take into account that the America's Cup rules, at that time, required that the hulls be catamarans, what option was left?. The monhulls were not obsolete, they were simply not allowed to compete by the rules of the competition. The opposite happens with current regulations, catamarans cannot compete but that does not mean that they have become obsolete.
On the other hand, the beauty of competitions is that the best design does not always win. Many designs, without being the best, win because the driver or the athlete is the best of all.

 

[Skyak]

As someone who raced single sculls for many years and have rowed many different sliding seat rowing boats, I have to comment on the Nelo video.
Sliding seat racing sculls have changed very little re length, width, hull profile since the 1890s. To say they are a highly evolved design would be understatement.
Many manufacturers over the years have deviated from the tried and tested (lowest theoretical wetted surface area) U shaped hull profile built appropriately long and slender to adhere to the rules and mechanics of the rowing stroke. And often they have flattened the hull bottom a bit near the centre of the hull (although this one leaves the hull near the centre U shaped and flattens the hull bottom at bow and stern.
Flat sections near the centre of the hull do make a boat noticeably slightly easier to 'sit' ie., more stability, making novice rowers often faster simply because they get to keep their blades from striking the water a bit better on the recovery. Not sure what completely submerged flat sections at bow and stern on a displacement boat with very little rocker would do, if anything.
Going for marketing driven/ design differentiated designs like Nelo has here is a viable strategy for a newcomer brand in a sport like rowing, but an uphill struggle. The thing is, squaring off the U shaped underwater profile or similar relatively small tweaks will not noticeably detrimentally affect the performance but they will make it look noticeably different and draw comment. But in a sport where athlete genetics and skill are 99% of the performance the better athlete will basically always win, within reason regardless of boat.
So in the 1990s everyone fast was racing Empacher sculls (probably initially because they were the Olympic pool boats for a period and US colleges started to think they made fast VIIIs at one point for some reason- so better athletes started getting their ( yellow with black ends ) Empacher singles, they were seen winning more races, so people thought they were faster boats.), then there was a brief excitement/ flirtation with US manufacturer Fluid Design, who had the marketing story of the first 'CFD designed' single scull, or 'shell' if we're talking American. Same thing, a handful of faster athletes got them and won some big races. Then, from about 2005 an Italian builder, Fillipi started to be the Go-to boat, can't remember why that one ignited now, but you then started to see a lot of them in Olympic finals, then shortly after every rich guy at your rowing club had one. Didn't make them any faster though...

So, because the Nelo is going to have a speed potential within 0.5% of any other reasonably recent boat out there ( whether it's 0.5% faster or slower is actually a moot point), all that actually matters is that they get them in the hands of a critical mass of very fast (like Olympic finals fast) single scullers, and then the world will consider them a fast boat. Actually measuring, objectively, the potential speed difference between this new Nelo, or a Fillipi, or an Empacher, or a Chinese boat brazenly moulded straight off an Empacher (no registration of designs or IP of any kind allowed in Olympic class rowing equipment!), is impossible. Or rather they are all so close to each other to be unmeasurable. Squaring off slightly a displacement hull well underwater will slightly increase its wetted surface area, but so little it would be unnoticeable. The psychology though of an athlete that thinks it is faster, especially if the competition also fears it is faster than their boats- now that is potentially hugely significant.

Having said all that, I do like what Nelo have been doing. I also paddle race SUPs and follow development there, and Nelo launched a hollow, ie not foam filled carbon SUP, which was a first, made sense and something I was wondering when someone would finally do it. Unfortunately, in similar scenario to single sculls described above Starboard have all the fastest male and female SUP racers on their kit, so even if the Nelo board was, say 5% faster, nobody would actually ever find out! SUP isn't an Olympic sport so the range in speed between the people at the front of the fleet compared with the people even 10 places back is other worldly. Catch 22 for new entrants like Nelo, unless they can catch athletes that are unsponsored, very up and coming, and hugely gifted.

But I love it that Nelo are trying this stuff.

I think this is your most useful and inciteful post yet. Why did the boatbuilder add the doohickey to their new boats? To sell boats!

If you lose to an athlete in a boat that is no different than your own, do you buy a new boat? NO!

There was a wonderful American woman I follow that set her mind to winning an Olympic gold medal. She looked at her options and decided that C1 was the sport that would give her the best chance of success. The kicker was she would be the first American woman to win C1 -and she did. I mention her because she clearly didn't have smoothest ride -quite the opposite. She was the smallest woman with the highest amplitude motion and the highest frequency of strokes.

I am a fan of Nelo too, but the suggestion that flattening the hull results in gain through "lift" is silly. Any lift on such a super low aspect surface will put most energy into a vortex. That vortex so early in the hull will affect wave development and drag. I think the positive aspect, if any, is the increased damping of the rocking resulting in a better feel -possibly attracting more talented rowers. I think a superior result could be achieved by simply sticking a little high aspect T foil rudder on any old elliptical section skull.

I was walking past the Nelo booth at a boat show and the guy invited me to try out their kayak paddle simulator. It felt surprisingly realistic. A crowd soon developed, and security stopped it all before I got to talk about it. I am not sure but I think that guy had a few Olympic K1 golds himself -I saw him in videos later. My point is that just because these races are 99% athlete, doesn't mean that you have nothing to sell them. You can pay winners, or you can build winners!