Yeah it's pretty amazing. I wonder if his comparison to the X-1 is right. That now the barrier has been broken, we'll see even faster designs relatively rapidly. The margin by which he went over it seems to suggest it might. I also liked the part about the models disagreeing because there was no actual experimental data. It's easy to forget that sometimes today when computer models seem to explain everything.
If I interpret what I read correctly - that because of the new design there's no turning moment, and that hence there's no point at which the boat would capsize, and all energy is thus put into forward motion, that you can just put a bigger sail/wing on it to get more energy from the wind, and go even faster, linearly with the size of the wing (minus some extra weight overhead). Basically, if true and I'm not missing something, the only limit to the speed has become material strength and weight.
These kinds of boat, which are lifting out of water as they gain speed, are fast but can't really be used in real oceans unless the weather is nice because they can't handle big waves.
Sailrocket is no way inspired by Hydroptère, and in fact one might argue that they could not be more different:
Hydroptere works by countering the heeling moment caused by the force on it's sails and foils, with, basically, it's weight (it's weight times the distance between the center of gravity and the leeward foil) whereas Sailrocket works by having NO heeling moment and actually somewhat of a negative one, as the leeward hull can be seen lifting clear out of the water at speed.
Hydroptere lifts out of the water by using foils, which are basically wings that work in water (at the air/water interface actually, which causes a host of problems) whereas Sailrocket skims along on planing surfaces, just like a powerboat or a windsurf.
Finally, Hydroptere works on both tacks (wind coming from either side) where Sailrocket only works on one tack. Some fascinating workarounds for this issues have already been worked out by Bernard Smith by the way.
Check out the orientation of the "bridle lines" from either end of the wing, and the keel. When I saw that, it all went "click" in my head. This is just a wing tethered to the keel - like a kite, or a paragliger - the hull/fuselage and the spar and pods/floats are all just "unnecessary" bits, only used to hold the wing and keel in the required orientation to get up to operating speed. (I wonder if someone will build a version of this which jettisons all of the boat-like structure when it gets the keel and wing up to the speed needed?)
That's very close to the ideas floating round in my head right now. Something very similar to that, a super efficient "kite" (think more like the SailRocket sail or a glider wing), "tethered" underwater using this 50+knot cavitation tolerant foil technology. I'm guessing it'd need a fair bit of "stuff" to get it up to the speed where the wing and foil start to operate effectively, wich might either be jettison-able floats/spars, or perhaps some technique where it gets launched/towed up to speed - kind of like how big wave surfers use jetski tow-ins to get on to big waves at speed - I wonder what the world record rules would say about a 70+knot "sailboat" that need to be towed up to 50_knots to work at all?
"Vestas are one of the worlds leading developers and manufacturers of wind turbines for whom Malcolm is a senior test engineer." (http://www.sailrocket.com/node/136)
Very cool that a senior test engineer from the worlds largest with turbine manufacturers is able to take his domain knowledge and build a craft like Sailrocket.
As a side note: I have spent time on Vestas wind turbine blades (rappelling down them using ropes to inspect the fiberglass) and they are an amazing feat of engineering. You can't really appreciate their strength to weight ratio until you have been on the tip of a 40 meter blade.
Just curious, I frequently see turbine blades for wind installations hauled on a sort of "trailer" down the interstate. I put "trailer" in quotes because it's really two frames around the blade, one at the front and one at the rear. The strength of the trailer seems to be the blade. I'm always surprised when I see it, thinking surely that can't be safe? (But carbon fiber can be completely safe.)
Do you know about these? Would it be a good guess to say the blades are Vestas blades? Can you tell me more about their strength-to-weight?
There are some in my town too you see giant tubes and blades heading out of town towards the testing facility, 90 metre monsters.
It's funny this article is about wind I guess that's the point him being an engineer for Vestas. Here on the island I live on we often get windsurfers who come here because it's so windy.
Not only did he get to use his domain knowledge, Vestas let him use their facilities and gave him all the consumables. No wonder they are the world leader.
As a sailor I cannot imagine what those speeds must feel like. I got a chance to sail a Hobie 16 on San Francisco Bay and it was pretty amazing to see how fast it could go and I doubt we even hit 20 knots. Nicely done Larsen, nicely done.
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[ 3.5 ms ] story [ 56.9 ms ] threadhttp://en.wikipedia.org/wiki/Pegasus_class_hydrofoil
These guys have been at it for so long it is hugely deserved !
listen to his voice on the record's video (http://www.youtube.com/watch?v=wnjyusAgk8I ) I think it helps get a sense of it must be like sailing at that kind of speed
Which TFA doesn't mention at all.
Here's a Youtube video comparing the two:
http://www.youtube.com/watch?gl=BE&v=qzkulFGa4Mc
These kinds of boat, which are lifting out of water as they gain speed, are fast but can't really be used in real oceans unless the weather is nice because they can't handle big waves.
> The basic design he kept returning to was one proposed 50 years ago by an American rocket engineer named Bernard Smith.
I know next to nothing about speed sailing, but it seems like due credit is being given.
Hydroptere works by countering the heeling moment caused by the force on it's sails and foils, with, basically, it's weight (it's weight times the distance between the center of gravity and the leeward foil) whereas Sailrocket works by having NO heeling moment and actually somewhat of a negative one, as the leeward hull can be seen lifting clear out of the water at speed.
Hydroptere lifts out of the water by using foils, which are basically wings that work in water (at the air/water interface actually, which causes a host of problems) whereas Sailrocket skims along on planing surfaces, just like a powerboat or a windsurf.
Sailrocket, as indicated in the article, owes a lot to Bernard Smith ( seminal work : http://www.amazon.com/Sailloons-Fliptackers-High-Speed-Saili... )
Finally, Hydroptere works on both tacks (wind coming from either side) where Sailrocket only works on one tack. Some fascinating workarounds for this issues have already been worked out by Bernard Smith by the way.
Look carefully at this picture from the article:
http://www.wired.com/images_blogs/autopia/2013/01/ff_superca...
Check out the orientation of the "bridle lines" from either end of the wing, and the keel. When I saw that, it all went "click" in my head. This is just a wing tethered to the keel - like a kite, or a paragliger - the hull/fuselage and the spar and pods/floats are all just "unnecessary" bits, only used to hold the wing and keel in the required orientation to get up to operating speed. (I wonder if someone will build a version of this which jettisons all of the boat-like structure when it gets the keel and wing up to the speed needed?)
Just a kite tied to a "water kite"
That's very close to the ideas floating round in my head right now. Something very similar to that, a super efficient "kite" (think more like the SailRocket sail or a glider wing), "tethered" underwater using this 50+knot cavitation tolerant foil technology. I'm guessing it'd need a fair bit of "stuff" to get it up to the speed where the wing and foil start to operate effectively, wich might either be jettison-able floats/spars, or perhaps some technique where it gets launched/towed up to speed - kind of like how big wave surfers use jetski tow-ins to get on to big waves at speed - I wonder what the world record rules would say about a 70+knot "sailboat" that need to be towed up to 50_knots to work at all?
http://hydroptere.com/news/501/34/Flying-trimaran-to-tackle-...
http://www.transpacrace.com/
Very cool that a senior test engineer from the worlds largest with turbine manufacturers is able to take his domain knowledge and build a craft like Sailrocket.
As a side note: I have spent time on Vestas wind turbine blades (rappelling down them using ropes to inspect the fiberglass) and they are an amazing feat of engineering. You can't really appreciate their strength to weight ratio until you have been on the tip of a 40 meter blade.
Do you know about these? Would it be a good guess to say the blades are Vestas blades? Can you tell me more about their strength-to-weight?
It's funny this article is about wind I guess that's the point him being an engineer for Vestas. Here on the island I live on we often get windsurfers who come here because it's so windy.
http://www.youtube.com/watch?v=8Ow8QbXhZJU