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Texxas

Hurricane Jumping

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So, here on the Texas coast we're bracing for the oncoming hurricane, with 125 mph winds. And that got me thinking. That's freefall speed wind!

Would this be possible? Suppose you tethered a wingsuit flyer on a rope - would he be able to fly like a kite in a hurricane force wind?

Yeah, I know it would be dangerous. But theoretically possible?

After all, wingsuiters exiting high speed tailgates can actually climb upward for a few seconds relative to the plane. And that is only ended when drag and gravity takes over, But with a hurricane, the air speed would be constant. Like a horizontal exit speed that doesn't diminish from drag - a forward throw that lasts forever.

You can fly anything given enough air speed, surface area and control of the angle of attack. Just look at those high speed racing boats that hit a little wave wrong, lifting the bow, and the boat goes airborne. Boats can fly! They have speed and surface area, but no control once airborne...

And you have to control the angle of attack, so that you deflect the wind downwards, to make the object go upwards. Newton's law of equal and opposite reaction.

As a kid I never understood how a box kite could fly. But fly they do. Surface area to deflect the wind, the proper angle, and up they go. Even though it's just a box on sticks with a couple of fabric panels.

So, back to the theoretical wingsuit jumper. Suppose you tether him to a sturdy object in a hurricane force wind. Can he angle himself into the wind, and fly off the ground like a kite?

Inquiring minds want to know. And you have just a day or two to get ready for hurricane landfall.

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This is not any more risky than proxy flying I suppose. You would need to find the correct point to attach the tether. I think screwing an eye bolt through the sternum might work well.
Always remember the brave children who died defending your right to bear arms. Freedom is not free.

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Yes, it is possible.

Wingsuit testing has been/is being done in horizontal wind tunnels, loosely the same idea. Haven't seen it done on a single 'kite-line' yet. Or with any appreciable maneuvering.

Serious problems to consider-
1-100mph wind is a lot. It will probably be gusty and variable direction.
2-You will need a lot of training, planning, testing, previously undeveloped equipment(probably even a custom suit), procedures, and technique, and then practice. No doubt all of this will be expensive and probably worth it in itself.
3-You have to fly a wing suit anchored to the ground. You (the kite) have to create enough lift to overcome your mass AND all the drag in the system that relates to the kite line angle and lift vector. And remember that increase in lift also increases drag. Assuming you have control of your pitch axis(vector of lift as it relates to the kite line) and with a 0 degree angle (kite/you directly downwind and level with your anchor) best case you need to create about 130% the lift of your normal free-flight wing suiting. The lift needed to overcome this drag increases exponentially and to infinite as the kite approaches 90 degrees overhead.
4-Assuming this works, you have to get down without dying. And I hope opening a parachute is not very high on the options list
5-Still have to live through the hurricane.

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Calvin19

Yes, it is possible.

Wingsuit testing has been/is being done in horizontal wind tunnels, loosely the same idea. Haven't seen it done on a single 'kite-line' yet. Or with any appreciable maneuvering.

Serious problems to consider-
1-100mph wind is a lot. It will probably be gusty and variable direction.
2-You will need a lot of training, planning, testing, previously undeveloped equipment(probably even a custom suit), procedures, and technique, and then practice. No doubt all of this will be expensive and probably worth it in itself.
3-You have to fly a wing suit anchored to the ground. You (the kite) have to create enough lift to overcome your mass AND all the drag in the system that relates to the kite line angle and lift vector. And remember that increase in lift also increases drag. Assuming you have control of your pitch axis(vector of lift as it relates to the kite line) and with a 0 degree angle (kite/you directly downwind and level with your anchor) best case you need to create about 130% the lift of your normal free-flight wing suiting. The lift needed to overcome this drag increases exponentially and to infinite as the kite approaches 90 degrees overhead.
4-Assuming this works, you have to get down without dying. And I hope opening a parachute is not very high on the options list
5-Still have to live through the hurricane.



Darwin is always looking for new award candidates....B|
My computer beat me at chess, It was no match for me at kickboxing....

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Phil1111

***https://www.youtube.com/watch?v=7R6XG0iltlA

sure go big, what could possibly go wrong in 125MPH hurricane force turbulent winds?



Darwin award if there ever was one.

Hold my beer and watch this! :D
"Mediocre people don't like high achievers, and high achievers don't like mediocre people." - SIX TIME National Champion coach Nick Saban

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Calvin19

1-100mph wind is a lot. It will probably be gusty and variable direction.
2-You will need a lot of training, planning, testing, previously undeveloped equipment(probably even a custom suit), procedures, and technique, and then practice. No doubt all of this will be expensive and probably worth it in itself.
3-You have to fly a wing suit anchored to the ground. You (the kite) have to create enough lift to overcome your mass AND all the drag in the system that relates to the kite line angle and lift vector. And remember that increase in lift also increases drag. Assuming you have control of your pitch axis(vector of lift as it relates to the kite line) and with a 0 degree angle (kite/you directly downwind and level with your anchor) best case you need to create about 130% the lift of your normal free-flight wing suiting. The lift needed to overcome this drag increases exponentially and to infinite as the kite approaches 90 degrees overhead.
4-Assuming this works, you have to get down without dying. And I hope opening a parachute is not very high on the options list
5-Still have to live through the hurricane.


And let me add:

6) You should learn about lockout, a common problem with tethered (i.e. ground-launched) hanggliders and paragliders.

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billvon

***1-100mph wind is a lot. It will probably be gusty and variable direction.
2-You will need a lot of training, planning, testing, previously undeveloped equipment(probably even a custom suit), procedures, and technique, and then practice. No doubt all of this will be expensive and probably worth it in itself.
3-You have to fly a wing suit anchored to the ground. You (the kite) have to create enough lift to overcome your mass AND all the drag in the system that relates to the kite line angle and lift vector. And remember that increase in lift also increases drag. Assuming you have control of your pitch axis(vector of lift as it relates to the kite line) and with a 0 degree angle (kite/you directly downwind and level with your anchor) best case you need to create about 130% the lift of your normal free-flight wing suiting. The lift needed to overcome this drag increases exponentially and to infinite as the kite approaches 90 degrees overhead.
4-Assuming this works, you have to get down without dying. And I hope opening a parachute is not very high on the options list
5-Still have to live through the hurricane.


And let me add:

6) You should learn about lockout, a common problem with tethered (i.e. ground-launched) hanggliders and paragliders.

After a day of drinking we decided it would a good idea to "parasail" a square canopy. Additionally a good chance to cool off in the lake as it was a hot day. So a stratoflyer was rigged up behind the boat and into the gusting 10-15 mph winds I went.

I had experience with conventional parasails, PC's rigged as parasails and towed hang gliders. After about 1000' of towed distance, I had had enough. The variables of gusting conditions, lack of inherent stability along the line of travel overrode everything else.

Subsequently a more adventurous jumper I knew broke a leg and arm towing a square canopy behind a truck.

As previously posted, video's of the hurricane jumping are required, or it didn't happen.

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Lockout is an interesting phenomenon. technically speaking Lockout occurs when the aerodynamic lift and applied (kite line) force line up and remove any inherent stability of the system. (The lifting forces on the kite/towed aircraft are in line with the kite line/tow line). At this point weight shift control is drowned in the high forces of the line/kite system, and aerodynamic control (canopy steering lines,etc) are greatly decreased in effectiveness.

In a paraglider, parasail, parachute, or hang glider or other single-line 'kite' ground tow this is avoided by limiting the force on the tow line throughout the flight. Obviously it works very well.

However, in the case of winch-tow sailplane launches the aircraft is not stabilized in pitch by the tow line, almost all pitching (AOA) is controlled souly by the pilot, allowing for relatively high tow line forces while maintaining full control of the kite/tow line system. The high line load is closer to in-line with the lift force of the wing, but not an issue because of the pitch authority the aircraft has.

When I mentioned "assuming you have pitch control" I mean the ability of the wing suit pilot to have very high authority on lifting forces, (being able to dump lift by drastically changing the shape of the wing, etc). In kite surfing, kites that have a different kite-line system to allow for drastic changes in the lifting vector of the kite. Forces on the kite lines are limited by the mass of the pilot, as the pilot is not an anchor but an inertial mass.


Me and the late Alex G spent a summer getting "good" at towing 220-260 square foot BASE canopies behind a car. using a 2000' 550pound test nylon line the only load limiter was the stretch(>30%) and final absolute -strength- of the line, and it did save us a few times. From what I have read of other people doing this the consistent problem i saw was using a static rope as the tow line with a release mechanism that required action (as opposed to inaction like our release system uses). In a lockout on a static line,(almost) the only thing that can save you is usually releasing from the line, so having to reach for a handle when the system is highly loaded(handles out of reach, in the wrong place, or overloaded/deformed into an un-releaseable state causes inevitable uncontrolled contact with the ground or obstacle. We used this system to do countless flights up to ~1200' with no injuries and the only 'close calls' were from the line failing or voluntary release at a low altitude near-lockout state where the pilot would not have the altitude to make a turn, has to land near straight-ahead. Please note that the car tow on a static line is physically identical to high-wind anchoring of a kite.

This is an interesting academic discussion. I hope everyone reading this appreciates the insanity needed to attempt fixed-line towing/kiting without proper understanding and equipment.

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