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cbuilder

home made wind tunnel

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My neighbor has been watching me skydive and tunnel fly for a couple of years and has decided to build a wind tunnel in his back yard. He plans to use a motor and blade from a wind boat (like what you see in swamps). Although he is an engineer, i feel it is a waste of time, money, and will turn our neighborhood into redneck rivera. Any thoughts on if it will work or why it won t so i can prove to him to stop.

PS i hope it works and so do my kids

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My neighbor has been watching me skydive and tunnel fly for a couple of years and has decided to build a wind tunnel in his back yard. He plans to use a motor and blade from a wind boat (like what you see in swamps). Although he is an engineer, i feel it is a waste of time, money, and will turn our neighborhood into redneck rivera. Any thoughts on if it will work or why it won t so i can prove to him to stop.

PS i hope it works and so do my kids



You need to create a substantial amount of airflow which requires a large electric motor. I doubt your average domestic supply is rated to supply enough current.

Secondly you might want to point out that safety is a major concern it might turn out to be a giant human mincing machine.
Experienced jumper - someone who has made mistakes more often than I have and lived.

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Long ago and far away I heard about the first wind tunnel. I drove over to see it. It was about a 4 foot tube perched on top of a flat bed semi. The engine and prop were mounted under the truck. The tube had no top. As I got out of my car this guy appears out the top of the tube. Balanceing on the column of air. I watched him flair for a few seconds, then he fell off the column of air and onto the ground. He made this loud thud and then for some reason started screaming. I walked over to observe his one femur bent at a rather odd angle.
I thought to myself "hmm". Got back in my car and left.
U only make 2 jumps: the first one for some weird reason and the last one that you lived through. The rest are just filler.
scr 316

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My neighbor has been watching me skydive and tunnel fly for a couple of years and has decided to build a wind tunnel in his back yard. He plans to use a motor and blade from a wind boat (like what you see in swamps). Although he is an engineer, i feel it is a waste of time, money, and will turn our neighborhood into redneck rivera. Any thoughts on if it will work or why it won t so i can prove to him to stop.

PS i hope it works and so do my kids



Get video.

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Takes a lot of HP to do it right. Our local tunnel routinely burns 300 KW and much more for head down flying.

I saw homemade tunnel on a flatbed. Had A Detroit 12-71 diesel driving a DC 3 prop through a right angle gearbox. A 12-71 puts out at least 550 HP.

377
2018 marks half a century as a skydiver. Trained by the late Perry Stevens D-51 in 1968.

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Takes a lot of HP to do it right. Our local tunnel routinely burns 300 KW and much more for head down flying.

I saw homemade tunnel on a flatbed. Had A Detroit 12-71 diesel driving a DC 3 prop through a right angle gearbox. A 12-71 puts out at least 550 HP.

377



Your post got me thinking. I wonder how slow/low power you could fly with the appropriate custom made suit in a tunnel? Wing suits probably wouldn't work in a tunnel as if I am correct in my understanding they glide. I am thinking that if you could increase your surface area substantially by having fabric between your arms and legs, and also between your legs and then you "flew" in a giant X you would be pretty low speed (provided you were strong enough to cope with the extra drag of course).

Would be a fun experiment and I imagine with spotters pretty safe.
Experienced jumper - someone who has made mistakes more often than I have and lived.

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The earlier tunnels, like the Aerodium (was northeast of Montreal in St Simon, circa 1980's), used to have 'balloon suits'. They had mesh vents to help the suit inflate to create more drag. However, that type of suit greatly limits what you are able to do in the tunnel. I was fortunate to be lighter so was able to use an old super baggy jumpsuit which at least allowed me to do flips, etc.
While it was fun back in the day, I would never waste the time or money building a tunnel with a severe restriction like that.

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The earlier tunnels, like the Aerodium (was northeast of Montreal in St Simon, circa 1980's), used to have 'balloon suits'. They had mesh vents to help the suit inflate to create more drag. However, that type of suit greatly limits what you are able to do in the tunnel. I was fortunate to be lighter so was able to use an old super baggy jumpsuit which at least allowed me to do flips, etc.
While it was fun back in the day, I would never waste the time or money building a tunnel with a severe restriction like that.



Yes I have flown in a lower power tunnel that needed very baggy suits. I don't mean that you should consider building a tunnel but it might be fun to hold the record for the "slowest flight in a wind-tunnel" in the Guinness Book of Records as an example.
Experienced jumper - someone who has made mistakes more often than I have and lived.

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The earlier tunnels, like the Aerodium (was northeast of Montreal in St Simon, circa 1980's), used to have 'balloon suits'. They had mesh vents to help the suit inflate to create more drag. However, that type of suit greatly limits what you are able to do in the tunnel. I was fortunate to be lighter so was able to use an old super baggy jumpsuit which at least allowed me to do flips, etc.
While it was fun back in the day, I would never waste the time or money building a tunnel with a severe restriction like that.



Yes I have flown in a lower power tunnel that needed very baggy suits. I don't mean that you should consider building a tunnel but it might be fun to hold the record for the "slowest flight in a wind-tunnel" in the Guinness Book of Records as an example.



Not to hijack the thread, but it's an interesting point.

I'm 5'5", weighing 120lbs. Last week at SVCO I put on an XL suit and hopped in. Was flying somewhere around the mid-40% range (& really working at it). I imagine someone skinner
& taller might be able to slow it down even more.

As an aside, backflying = bad idea. Sitflying = worse idea. Belly & HD are about all you can do without the suit beating you up.

The difficulty is in standardizing the wind speed. When the tunnel indicator says "120mph," for instance, it's not really accurate. That's why most tunnel flyers just quote percentages for that particular tunnel (i.e., topped out = 90% of tunnel capacity. Avg. belly = somewhere around 70%...etc.)

Comparing who's flying the slowest would be difficult, except on a tunnel-by-tunnel basis.

/end thread hijack
Signatures are the new black.

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Long ago and far away I heard about the first wind tunnel. I drove over to see it. It was about a 4 foot tube perched on top of a flat bed semi. The engine and prop were mounted under the truck. The tube had no top. As I got out of my car this guy appears out the top of the tube. Balanceing on the column of air. I watched him flair for a few seconds, then he fell off the column of air and onto the ground. He made this loud thud and then for some reason started screaming. I walked over to observe his one femur bent at a rather odd angle.
I thought to myself "hmm". Got back in my car and left.



everyone that I work with just looked over at me at the same time when I read this and laughed out loud like a dweeb.
Moriuntur omnes, sed non omnes vixerunt.

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its all possible for him to make it, my company made a 'wind generator', using a diesel engine and 2 props of a helicopter. this was used to test wind turbines on the early development of the project. if you get the right blades with gear box and some money, can do at least belly fly
Julio Cesar
blue skies

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The capital investment for a "real" tunnel is nuts.
It's bombasticaly expensive but everyone thinks it's a good idea.
How can I put it?
Everyone wants one, the profit potential looks "good" but no one is willing to throw down the huge capital needed to get one "off the ground" [:/]

So why no?

Life through good thoughts, good words, and good deeds is necessary to ensure happiness and to keep chaos at bay.

The only thing that falls from the sky is birdshit and fools!

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Maybe you could contact these guys http://www.skydivenovisad.com/tunel.html.

I think they use ~500HP T-55 tank engine and AN-2 prop. It looks like this tunnel is underpowered for flying in regular jumpsuits and thus they fly in big baggy suits. The guy who made it tried to get stronger tank engine ~1000HP but i think this did not happen. You could try to contact him directly. Look for Sasa Jojic.

There is also this one in my vicinity that i know of.
dudeist skydiver #42

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for a dollar id buy it!

....now how to get it home. i hope my neighbors dont find it too loud. .. :ph34r:

Thanatos340(on landing rounds)--
Landing procedure: Hand all the way up, Feet and Knees Together and PLF soon as you get bitch slapped by a planet.

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