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steering at 52.8 knots...


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OK, so this one is not on water, but the speed is unbelievable. And what about the wing. Is that the secret and could it be implemented on something like the Sailrocket?

 

That would work fine on the water but the friction co efficient would be different between the two mediums.

 

and the foil shape would need to be tweaked

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What a very clever design idea for the sail though. I don't quite understand how the machine would control it's speed, mainly just stopping. Because it doesn't look like he can sheet the sail.

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What a very clever design idea for the sail though. I don't quite understand how the machine would control it's speed, mainly just stopping. Because it doesn't look like he can sheet the sail.

Think you'll find the sheeting arangement is inside the "hull"/body and there is a lever attached to the rig between the bottom bearing and deakhead "top" bearing.

 

Moving the lever will be either a hydraulic ram or a block and tackle system.

 

If there isn't then this is very.... cunning!

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What a very clever design idea for the sail though. I don't quite understand how the machine would control it's speed, mainly just stopping. Because it doesn't look like he can sheet the sail.

Think you'll find the sheeting arangement is inside the "hull"/body and there is a lever attached to the rig between the bottom bearing and deakhead "top" bearing.

 

Moving the lever will be either a hydraulic ram or a block and tackle system.

 

If there isn't then this is very.... cunning!

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I am not sure there is. May be wrong. But notice the sail (if it can be called that) moves quite freely and does so up to quite a speed. Then it starts to rock steady up. I think that is the point where the Apparent Wind over powers the Actual wind and the eddies in the wind no longer affect the Sail. The tail is what is keeping the Sail to the correct angle through the entire run. And that is the part that interests me the most.

In thinking about that, I wonder if the Tail piece has a controllable movable foil, that the "Helmsman" can adjust. That would make sense. Then the tail is steering the Sail. Now that would be very clever.

We are not talking a small speed here. That is 150MPH

I am also not so sure friction would be a lot different. One of the biggest issues is keeping the fast water machines down on the water. They require foils to "grab" the water to hold them down. That is not possible with a Tyre. The Tyre is only going to stop lateral movement and maintain a direction of travel. I imagine that "grip" would be getting rather thin on it at 150MPH. I am not sure how it stayed on the ground.

Here is why explained in basic physics.

A craft powered by the wind, moves because ultimately there are unequal forces. These forces are used in such a way as to create movement. Once a wind powered craft reaches a point in speed, the forces start to cancel out and eventually, what was holding it down, now doesn't. The only way top over come that is to create more down force. Which results in more of that energy wasted as drag. So the real game is to reduce drag as much as possible, but still keep everything on the ground, or water. So at 150mph, that is quite some feat.

However, there is one small slight difference between water and Dirt. Or salt as that speed attempt was on. The air temp at the surface. Water has a cooler air temp and thus a denser air layer on and just above it's surface. The Salt flat will be hot as hot and the air layer will be much thinner so the boundary layer affect will not be as pronounced. And in a small way, there is also the fact that the water always has bumps on it, which doesn't help either. At that speed, a ripple is like hitting a rock. Trust me, i know what those ripples feel like at 80Mph on skis. ouch.

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I am not sure there is. May be wrong. But notice the sail (if it can be called that) moves quite freely and does so up to quite a speed. Then it starts to rock steady up. I think that is the point where the Apparent Wind over powers the Actual wind and the eddies in the wind no longer affect the Sail. The tail is what is keeping the Sail to the correct angle through the entire run. And that is the part that interests me the most.

In thinking about that, I wonder if the Tail piece has a controllable movable foil, that the "Helmsman" can adjust. That would make sense. Then the tail is steering the Sail. Now that would be very clever.

We are not talking a small speed here. That is 150MPH

I am also not so sure friction would be a lot different. One of the biggest issues is keeping the fast water machines down on the water. They require foils to "grab" the water to hold them down. That is not possible with a Tyre. The Tyre is only going to stop lateral movement and maintain a direction of travel. I imagine that "grip" would be getting rather thin on it at 150MPH. I am not sure how it stayed on the ground.

Here is why explained in basic physics.

A craft powered by the wind, moves because ultimately there are unequal forces. These forces are used in such a way as to create movement. Once a wind powered craft reaches a point in speed, the forces start to cancel out and eventually, what was holding it down, now doesn't. The only way top over come that is to create more down force. Which results in more of that energy wasted as drag. So the real game is to reduce drag as much as possible, but still keep everything on the ground, or water. So at 150mph, that is quite some feat.

However, there is one small slight difference between water and Dirt. Or salt as that speed attempt was on. The air temp at the surface. Water has a cooler air temp and thus a denser air layer on and just above it's surface. The Salt flat will be hot as hot and the air layer will be much thinner so the boundary layer affect will not be as pronounced. And in a small way, there is also the fact that the water always has bumps on it, which doesn't help either. At that speed, a ripple is like hitting a rock. Trust me, i know what those ripples feel like at 80Mph on skis. ouch.

 

 

Agree totally and noticed it moving very freely but thought that he may have just let it do this to maintainn speed without wipeing out.

 

But thinking about it, it just finds it own apparent wind and self adjusts to produce powere with minimum friction (keeping even pressure either side of the wing?)

 

The wing is free standing and gives lift like any wing but just transferrs it differently.

 

They should call it Weasel... very cunning!

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