http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/ Engadget Comments for http://www.engadget.com/media/feedlogo.gif http://www.engadget.com en-us Copyright 2012 Weblogs, Inc. The contents of this feed are available for non-commercial use only. Blogsmith http://www.blogsmith.com/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:16PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:49PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
when your craft is sailing in 15 knots of wind, you'll find that trimming and
sailing up wind you can realize maybe 22 knots of wind in your face because you're moving into the wind.
sailing that rig that fast is amazing. I'm only familar with sailing boats, but having seen ice boats...
they're sort of like this... sort of.]]>Mar 27th 2009 11:54PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
The solution is tacking the vehicle. lets say the wind blows due north at 30 mph, and we know this car is going 126 mph. In an ideal world, this means that the final vector must be 126 mph (obviously) at a heading of 76.2 degrees ENE. Where does the 76.2 come from? The cosine of the record setting angle must equal the ratio of the wind divided by his speed. Hence; cos-1(30/126)=76.2. Considering losses due to friction, his tack must have been greater than 76.2 degrees off of the winds direction. More than likely, his approach started directly aligned with the wind. As he approached the winds 30 mph, he would have slowly turned his vehicle while keeping the sail perpendicular to the wind. Assuming a steady wind and gradual steering, his speed would have peaked at 126 mph. He would then make slight adjustments until he was at his percieved maximum velocity. (this heading, as stated above, would be >76.2 degrees, and less than 90 degrees for obvious reasons.)
Is everyone on the same page now?]]>Mar 28th 2009 12:06AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
...pull my finger...]]>Mar 28th 2009 1:24AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
Start making chicken. When done cooking, get in the car, say:

"Alright. Time's up, lets do this! RIIIIIIIIIIIIIICHHHAAAAAAAARD JEEEEEEEEEEEEEEEEEEEEEEENKIIIIIIIIIIIIIIINS!!!!!"]]>Mar 28th 2009 5:06AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
http://www.boatdesign.net/gallery/data/500/alcyone.jpg

This car uses the same tech.
Basically, you have a wing, set on a rotating platform. It faces the wind and creates lift as the wind passes around it, this lift is translated into forward motion for the car.]]>Mar 28th 2009 5:10AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
It really is very simple. Think of an aircraft wing, with a horizontal airflow. The wing provides lift vertically (at 90 degrees to the airflow) . Ok, so now put this wing upright (vertical) on a vehicle, such that the wing is 'sideways' to the car's direction of intended forward motion. A wind blowing across the wing will provide 'lift' the same way it provides lift to an aircraft, but instead of the force being 'up', the force is now 'forward', so the vehicle is propelled with a thrust component which is acting at 90 degrees to the direction of the wind. The fact that the wind is only 30MPH is irrelevant, as is all the cosine equations nonsense. The wind is coming from the side, so relative airspeed is also irrelevant and the forward thrust from the wing will remain constant, accelerating the vehicle until the drag component from it's forward motion equals the thrust component of the wing.

http://www.greenbird.co.uk/about-the-greenbird/how-it-works]]>Mar 28th 2009 8:26AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 8:53AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 10:38AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:17PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
The 30 mph wind is not pushing the car directly from the back, but at an angle, so that even though the car is traveling at 120mph, the component of its vector in the direction of the wind is less than 30mph.]]>Mar 27th 2009 11:23PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
What's a vector?]]>Mar 27th 2009 11:29PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
so obvious]]>Mar 27th 2009 11:34PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
A vector is a quantity of magnitude and direction. An example is a person jogging 5 mph north. 5mph is magnitude, north is direction]]>Mar 27th 2009 11:34PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:53PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/okay, the "car" is moving in one direction lets say north.
the wind is moving east to west. -->\
you set your sail facing the wind at a 45 degree angle (like this: --wind-->\ sail
the wind pushes against you (always) at 30 mph, the 45 degree sail -->\
turns the wind from a horizontal into a vertical movement.
so, you can get 120 mph on a 30 mph wind.

well, at least thats how i understand it.]]>Mar 28th 2009 12:01AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
i think i got it.
okay, the "car" is moving in one direction lets say north.
the wind is moving east to west......................................................-->\
you set your sail facing the wind at a 45 degree angle (like this: --wind-->\ sail
the wind pushes against you (always) at 30 mph, the 45 degree sail....-->\
turns the wind from a horizontal into a vertical movement.
so, you can get 120 mph on a 30 mph wind.

well, at least thats how i understand it.]]>Mar 28th 2009 1:06AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:38PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
Granted, I really have no clue. But that sounds the most logical to me.]]>Mar 27th 2009 11:54PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/b. you should make that, sounds like a good idea.]]>Mar 28th 2009 12:27AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:49AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
Anyone kid could would know that the sail car just caught a brief 126 mile per hour gust of tail-wind as it went through the traps.]]>Mar 28th 2009 5:53PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
The wind is the engine, it's just a force. You can collect as much energy out of it as you want, and that's determined by the size of the sail.

The sail is a variable speed transmission, the angle of the sail with respect to the wind determines how fast you move. If it helps to relate to cars. The wind is a very low rpm engine, but with TONS OF TORQUE. And just like in cars, there's no direct link between the rpm peak and the top speed.

Imagine a scenario where the wind is blowing directly from the side. You start from 0mph, which means your sail is parallel to the wind (no wind is actually hitting the sail), then you begin tightening the sail. @45deg the wind is deflected exactly 90 degrees, thus your speed is equal to the wind. Turn the sail toward perpendicular to the wind, and your transmission reaches infinity.

(in reality it works NOTHING like this, but the principal is still the same). The main principal of these speed demons is to make these vehicles more theoretically simple (without resistance, without drag, without turbulence, etc.).]]>Mar 29th 2009 3:42AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:44PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
My thermodynamics is rusty.]]>Mar 27th 2009 11:44PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
But thanks for playing!]]>Mar 28th 2009 12:00AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/76.2 degrees, and ]]>Mar 28th 2009 12:01AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/ "less than 90 degrees for obvious reasons.) Get it now?"]]>Mar 28th 2009 12:04AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:46PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:49PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:28AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 5:13AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
You've explained to all of us why this is happening but not HOW it happens. So it is one thing for you to tell everyone it is like a sailboat and it has to do with the vector of the forces by the wind, but you still have not even begun to explain HOW this enables travel faster than wind speed.]]>Mar 27th 2009 11:47PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/sailing down wind it will never be faster than the wind speed ever.
but it can move across the wind... even angle up wind and
since the wheels have little drag on the flats, and the craft is soo slippery
in the wind, it can keep accelerating beyond the wind speed recorded
if you were standing still.]]>Mar 28th 2009 12:00AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.youtube.com/watch?v=xHsXcHoJu-A]]>Mar 28th 2009 2:47AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
interesting.... but the craft does not sail.

I can see why people especially sailers
would refute this as sailing, not sure you agree.

]]>Mar 28th 2009 4:38PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:47PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 10:58AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 27th 2009 11:52PMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
wind at 30mph

when car moves at this speed it is still only moving at a speed of say 10mph with respect to the wind at an angle

so from the perspective of the car when it is moving at 120mph there is still a 20mph wind blowing on it

thats the general gist of it]]>Mar 28th 2009 12:01AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:03AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:08AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 5:40AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.boatsafe.com/kids/bramp1099.htm

The following is oversimplified but easier to understand. If you're going the same direction of the wind, you can only go as fast as the wind (minus friction of course). If you're at an angle you're constantly adding the velocity you gain from deflecting wind from the side to the rear (equal and opposite reaction) to the velocity you already have, allowing you to (in time) go infinitely fast in theory if you disregard friction, friction is what limited him to 126mph]]>Mar 28th 2009 12:26AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
It might be easier to visualise components if you imagine a pixel grid on a screen. To make a vertical line, you move up five pixels. To make a horizontal line you move across five pixels. But to make a diagonal line you must move across five pixels then up fixe pixels and join up the result. This isn't directly analogous but it gives you an idea.

First we assume North/South is up/down and East/West is across. We will be using the equation:

(Vertical component) = (car's velocity) * sin(angle between the car's direction and the horizontal)

Imagine the wind is travelling 30MPH North. If the car travels North too then it can expect to reach about 30MPH (excluding frictional forces). At this point the vertical component of its velocity is 30MPH and the horizontal component is 0MPH. However when the car is at 15MPH, the vert. is 15MPH and the horiz. 0MPH, but the wind speed (north) is still 30MPH vertically so the car will accelerate until the vertical component of its velocity matches that of the wind.

Now we move the car so that it is, for example pointing North-East (angle 45 deg.). When it is moving 30MPH North-East, its vertical component is 30*sin(45) = 21.2MPH, so it will accelerate until its vertical component matches that of the wind. In this case that's 30MPH so we can work out by rearrangement of that formula the car will be travelling 30/sin(45) = 42.4MPH.

So, for the car to be travelling 126MPH, with a vertical component of 30MPH, its angle from the horizontal will be roughly:

sin^(-1)(30/126) = 13.8 degrees.

To summarise: if the wind direction is North, the the car will have been travelling 14ish degrees above East to achieve this kind of speed.

I hope this helps you to understand even a little! Reply if you need any more info.

--nimro]]>Mar 28th 2009 12:30AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/
I should have said that this results in a direction of 76.2 degrees. Thanks to Tim above for seeing this ( I am glad our numbers agree!).

It's also worth noting, as others have done, that I am assuming no friction in these calculations. In reality, it is very difficult to achieve this kind of speed from wind because of friction.]]>Mar 28th 2009 12:34AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:43AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:45AMhttp://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/http://www.engadget.com/2009/03/27/wind-powered-vehicle-hits-126mph-nabs-world-record/Mar 28th 2009 12:52AM