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mdrejhon

Wingsuit TAKEOFF from a ski slope without ramp -- possible?

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Hello,

First, some interesting facts:
- The world record in ski racing is 156mph (251.4kph) - clicky
- Ski jumping using a ramp can reach 60mph (100kph) - clicky
- The speed of the successful wingsuit landing was ONLY 50mph glide (many references, video speed measurement seem to agree)
- Wingsuit flare angles approximately overlap ski jumper angles.

Do you think a short wingsuit takeoff from a ski slope is possible? Even if just a few seconds, even 1-2 seconds? Essentially, ski-jumping without a ramp? I believe so, based on my research.

The technique, in theory:
1. You're already experienced in ski racing and wingsuiting.
2. Find a very long, steep straight ski slope.
3. Wear a big wingsuit and racing skiis (flexible ultralight race bindings, not boots)
4. Race down the slope, kneeled with wingsuit collapsed.
5. Achieve at least 100kph (less than 1/2 world record)
6. Halfway down the slope, suddenly stand up and flare with wingsuit.
7. You're flying in the air for a few seconds, before touching down, ski-jumper style.
8. You land, before the end of the steep slope.
NOTE: Due to wingsuit fabric hanging out even if collapsed, you'll need to race harder to overcome the resistance of a collapsed wingsuit. For example, you may need to as if you're going 130kph in order to reach the needed approximate 100kph for takeoff speed.

Practice technique, in theory
1. Become good at wingsuiting.
2. Become reasonably good at ski racing (straight runs).
3. Become reasonable good at ski jumping.
4. Race down ski slopes while wearing wingsuit. Just to get a 'feel' of the air resistance.
5. Beginning at slow speeds, flare your wingsuit while going down a slope. Just to lighten your weight by about 20 or 30 pounds off your feet. Fly your wingsuit while you ski downhill.
6. Practice until you're good at balancing yourself using wingsuit while skiing.
7. Progressively go faster, while flying more and skiing less. More weight in the airflow and less weight in your skiis.
8. Rinse and repeat.
9. Do trial runs with you eliminating more than 50% of the weight off your feet, so you're mostly flying your wingsuit while skiing downhill.
10. Flare more and more during the middle of long steep slopes, so you've eliminated 70-80-90% of the weight off your feet while you're flying wingsuit while skiing.
11. Finally, on your real run, ski at least 100kph and then flare your wingsuit sufficiently enough to take off, to fly above the slope by a few feet for 1-2 seconds.
12. You land conventionally like a ski racer. Except there's no ramp, you took off using the wingsuit rather than off a ski ramp.
13. Rinse and repeat, achieving longer flights above the ski slope.

(Theoretically, you can move on to attempt this from an airplane; and land on the ski slope. You'd have to throw in other training, such as practicing GPS runs at high altitudes first, too, and maybe also practicing low flights over a slope with a BASE parachute first -- like that Solomon promo a few years ago. But you don't really need to go quite that fast.)

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I do think its definitely possible, but from looking at it in an engineering aspect, the wingsuit would need to be re-designed.

Just like how an airplanes fins change for take off, flight and landing. There would need to be a special "take-off" designed wingsuit.

...or at least for better and more efficient results.

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I'm voting no. The problems are in the orientation of wingsuiting vs. skiing, and that they're not the same.

Think about the angle of attack you need to fly a wingsuit, and then think about what position you would need to be to achieve that angle to the relative wind as you ski down a hill.

Add in the drag of the skis once you lift off, and you can see that you would need to far exceed the 'ideal' minnimums wingsuiters achieve in 'perfect' conditions.

Presumably if you had a hill that was steeper than the glide ratio of the suit, and some sort of detachable skis that you could lean forward on, you might be able to convert a tpo speed, fall line run into a launch, but that would be skecthy at best and dangerous as shit. You would stand a great chance of taking a head-first tumble down a serisouly steep mountain.

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actually I'm curious how you think the angle of attack is much different from a ski jump? I was under the impression that your feet are the low point flying a wingsuit much like your feet are the low point getting air off a ski ramp.

I think it would be much more doable to ski off a jump in front of a cliff and then open up the wingsuit while in mid air and start flying away. Hard still and an impressive feat! But I believe it has already been done so there's not the 'glory' though I'm sure it would get anybody going to do that :D

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Ski jumping skis are different than downhill skis. They are hinged at the toe so the jumper can lean forward into the wind and not have the skis perpendicular to the wind. Those skis, however, are not suitable for downhill-type skiing, they're prupose built for a ski jump.

On top of that, the ski jump ramp provides the initial thrust to toss the jumper away from the slope. So if you remove the ramp, and the purpose built skis, you have some problems.

In terms of skiing off a cliff, it's called ski-base, and has been done many times. They use a quick-release type of binding so they can jettison the skis right agter take-off, and the failure of one of those bindings is what lead to the death of Shane McConkey.

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oh yes I'm quite aware of ski-base...I believe it is a step up though to do WS ski-base :D

even that has been done though...whats left for the ego to feed on once all of these feats are accomplished? I'm sure somebody will think up even more ego-driven behavior:ph34r:

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Quick correction - WS ski-BASE has been done, and that's where they jettison the skis to allow for WS flight. Regular ski-BASE will sometimes (all the time?) keep the skis on, and just dump from a stand-up.

WS ski-BASe is how Shane was killed.

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whats left for the ego to feed on once all of these feats are accomplished? I'm sure somebody will think up even more ego-driven behavior:ph34r:



I suppose when you jump out of airplanes it is driven by altruism rather than ego?
www.WingsuitPhotos.com

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Think about the angle of attack you need to fly a wingsuit, and then think about what position you would need to be to achieve that angle to the relative wind as you ski down a hill.

Actually, with hinged skiis, you don't have to be perpendicular to the hill, and there's some flexibility as to what kind of angle you need to be. With a wingsuit, you have even more control over how much you lean during skiing: Leaning forward too far? Just add air resistance to balance. Leaning not far enough? Just reduce air resistance. This is clearly a very learnable human endeavour; skiiers already do this -- i.e. standing up vs. kneeling, and leaning forward slightly to compensate for sudden air resistance when you suddenly stand up (from kneel) during high-speed skiing. Already knowing fallrate control during skydiving, also somewhat semi-translates to this skill. This improved lean angle control that a wingsuit gives you, will somewhat compensate for the danger aspect. Just acclimate into this during low-speed ski runs while wearing wingsuit, until you're a pro at doing this at very high speeds. (In theory, at least). Now, you've got access to a wide 'lean' range, that overlaps some angles of certain intensities of wingsuit flaring.
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Ski jumping skis are different than downhill skis. They are hinged at the toe so the jumper can lean forward into the wind and not have the skis perpendicular to the wind. Those skis, however, are not suitable for downhill-type skiing, they're prupose built for a ski jump.

On top of that, the ski jump ramp provides the initial thrust to toss the jumper away from the slope. So if you remove the ramp, and the purpose built skis, you have some problems.

In terms of skiing off a cliff, it's called ski-base, and has been done many times. They use a quick-release type of binding so they can jettison the skis right agter take-off, and the failure of one of those bindings is what lead to the death of Shane McConkey.

This is the best feat-engineering question that come up in this thread. You are very right about the different types of skiis, for racing vs. jumping vs. recreation. It is very possible some custom ski hinge may be necessary to get the best of both worlds.

That said, if we're just skiing straight-line down a long straight slope, much like down a take-off ramp, one might only need some good ski-jumping skiis, since you're not going to be alpine-skiing during such an endeavour. On the other hand, such a slope may have different requirements that warrant some kind of compromise ski.

Mind you, there is definitely uncharted territory here - but the amount of untrainable uncharted territory is shrinking.

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Quick correction - WS ski-BASE has been done, and that's where they jettison the skis to allow for WS flight.

I intentionally added "without ramp" -- the thought experiment is the takeoff from a 'flat' diagonal slope.

That said, you do brings up an excellent observation: Jettisioning the skiis to allow flight. In addition to reduce entanglement risk with the BASE parachute, it is also presumably because previous wingsuit flights do not show good stability while wearing skiis. That's already observed, too.

...But have hinged ski jumping skiis EVER been used for a prolonged period during wingsuit flight, and attempting to angle the jump skiis aerodynamically to benefit flight, much like a ski jumper uses them to get a little extra distance? And if so, given the constraint that a wingsuit gives to your legs/feet, would any kind of hinge modification be needed to get skiis into a safe, stable, 'flight' configuration, that's easily controlled by your feet like for a ski jumper? I would presume that none of us are able to answer this question unequivocally, just yet...

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whats left for the ego to feed on once all of these feats are accomplished? I'm sure somebody will think up even more ego-driven behavior:ph34r:



I suppose when you jump out of airplanes it is driven by altruism rather than ego?

haha good point :S

I think there is a difference (I find at least personally not making a total judgment call about everybody) between ego-driven decisions and simply making decisions based on acheiving joy/bliss.

but im off topic sorry! B|

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I would envision more of a lay down toboggan, or like those plastic crazy carpet things that would keep you laying down until lift off, for sure it could be done, and quite safely. Maybe build two plastic runners into the front of the suit that you could steer a bit with elbows tucked in, then spread for takeoff..or maybe some snowboard type design you could lay down and steer by shifting.
A whole new fun sport, although hard to arrange a place to do it for 99% or us.

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I would envision more of a lay down toboggan, or like those plastic crazy carpet things that would keep you laying down until lift off, for sure it could be done, and quite safely. Maybe build two plastic runners into the front of the suit that you could steer a bit with elbows tucked in, then spread for takeoff..or maybe some snowboard type design you could lay down and steer by shifting. A whole new fun sport, although hard to arrange a place to do it for 99% or us.

It's an interesting concept, but observe the angles:

Gary's wingsuit landing angle:
http://laughingsquid.com/gary-connery-completes-first-successful-wing-suit-landing-without-using-a-parachute/

Ski-jumper angle:
http://visual.merriam-webster.com/sports-games/winter-sports/ski-jumping/ski-jumper.php
More images:
http://eyowf2011.cz/web/dgqsmz8a.html?lang=en

Also, even if the toboggan method was safer, what kind of progressive step-by-step training method would be possible with the toboggan method? Presumably we'd need some form of a low risk entry point to training towards a wingsuit landing. We need:
  • Low risk entry point
  • Easily controllable escalation of risk
  • Easily Allow progressive gear changes/adjustments
  • Create a larger audience to increase pool of potential 'extreme atheletes'
  • The Daredevil Factor: Strive to eliminate untrainable territory

Low risk entry point
That'd be wearing a wingsuit while skiing on a bunny/intermediate slope. That's obviously super-low risk. (Even you and I can do that) You progressively go faster on steeper slopes while learning & adjusting the gear for safety, and starting to fly the wingsuit more and more, while you're skiing, and it becomes strong enough to allow you to balance on your skiis, just by flying the wingsuit.

Easily controllable escalation of risk
Start on the bunny slope with wingsuit! It's nearly no risk at this point; I can do it, you can do it. Then intermediate, then black diamond. Steeper and steeper, gradually. Go from there. Eventually you may need to fly somewhere to visit a slope with a specially steep & flat slope, but you wouldn't need to start out with that. Just doing plain skiing on a recreational ski slope, while wearing wingsuit -- probably just jumping up gently (as if going from kneel to standing up, suddenly inflating your wingsuit) while skiing 30-40mph (I easily ski at least that fast, when wearing my old racing-style skiis) would allow you to hop up into the air a few inches and allow you to almost fly for short distances for up to one second. A skiier/wingsuiter could probably be able to 'learn'. I've tried a very minor amount of freestyle, and basically, freefly skiiers often assist their airtime with a little jump, a wingsuit would presumably 'add' airtime, even at low speeds of 30-40mph.

Wipeouts at 30-40mph typically isn't painful on non-icy, flat diagonal ski slopes, provided you're wearing appropriate gear. I have wiped out on skiis at over 30mph before -- no injury. You can control risk escalation during training, as you go to 30-40-50-60mph to the point wherre simple wingsuit takeoff may become possible just by the sheer airflow speed alone with no leap-assisted hop. Even though injuries become more frequent at higher speeds such as at 60mph (but quite survivable wipeouts -- can be still injury free -- deaths during wipeouts are caused by collisions with trees/rocks/obstacles as you skid at higher speeds into them especially during curves) -- careful choice of obstacle-free slopes would be warranted -- and escalation of risk during training, is thus more controllable, than the toboggan method. Learning stays at a measured pace.

Mathematically basing off the fact that flared wingsuit flight is 50mph -- flaring a wingsuit at 30-40mph should still be able to suddenly eliminate more than 50% of your body weight off your skiis. It is probably even within many of our skills today, to be able to do that. With such a big weight reduction, you can jump very high with just a small leap with your legs. In theory, if I ever tried wearing a wingsuit while I went skiing, I'd probably train no further than about 30-40mph (based on ski speeds I've gone already, and risk assessment), given a suitable long reasonably mogul-free steep slope, but some other skydivers/wingsuiters/skiiers may have the guts to realize they're comfortable at 50mph-60mph going downhill skiing while wingsuiting -- there are recreational ski slopes at some resorts in the world that can allow you to go this fast on quiet ski days and/or special close-off requests (rented slopes) -- these are now speeds theoretically sufficient enough to do short takeoffs from a ramp-free slope while wearing a wingsuit (by flaring the wingsuit). Eventually you'll need a really long steep run for the final practice attempts and the eventual wingsuit landing. This would help figure out the proper ski gear, given the constraints of the wingsuit restriction on legs, and leg separation, ability and timing of spreading apart legs versus bringing them back together at the last moment such as touchdown (ala ski-jumping spreading skiis V-shaped, then bringing skiis back together just right before touchdown), what is discovered to be risky or more risky during training during faster skiing, etc. You would not need to ever decide to skydive with the wingsuit, if you're just practicing towards wingsuit takeoff from a slope, as you're just doing big ski jumps using "wingsuit launch" rather than "ramp launch".

Create a larger audience to increase pool of potential 'extreme atheletes'
It's quite easy to just wear a wingsuit while skiing on a bunny slope. People jumping in the freestyle park of a ski resort, may resort to trying to wear a wingsuit to get 1/2 second more airtime during a plain freestyle jump. People who have no intention of doing anything else with a wingsuit other than to get a fraction of a second extra airtime. A few skydivers who are also skiiers, reading this post, might actually try to wear their wingsuit at their next ski resort visit, just to try it out, in just very ordinary situations.

Even at slow speeds, 20mph, 30mph, 40mph, that some of the everyday speedy skiiers often do, you can jump from the slope, and the wingsuit simply increases airtime a tiny bit because of the drag. Perhaps even a full second of airtime is possible, for a jump-assisted liftoff at ski speeds slow enough for harmless ski wipeouts. Therefore, I think that wingsuit takeoff from a ski slope is probably much easier/safer than doing a skydive and landing wingsuit on a slope without parachute -- since the risk escalation is so easily controlled (just simply start skiing on bunny slope with a wingsuit, and progress from there). Wipeouts are no big deal even at 30-40mph, as long as you're wearing proper protective gear. It seems like it would be safe enough to theoretically become a possible niche downhill-skiing discipline as popular (or moreso) than para-skiing, for people who might never skydive and land a wingsuit. At 30-40mph, you wouldn't need to choose much special gear other than a stock wingsuit from one of the main manufacturers, and lightweight stock skiis with freestyle ski bindings, and wearing a ski helmet with face shield, and off-the-store-shelf protection, all stuff you can get at a good ski gear store, you're ready to try jump-assisted wingsuit hops for a little extra airtime on existing slopes with what is probably low risk of extra injury over regular skiing that people already do anyway on the ski slopes... Who knows, maybe my post gives some skiiers some idea to try wearing a wingsuit at the slopes just to try it out at low speeds. (Disclaimer: It's not risk free. You can still die. Downhill skiiers still die too!)

Then, once a few dozen people have gotten the hang of plain skiing with wingsuits on for a second or two extra of airtime during hops (that many of us downhill skiiers often like to do anyway), some may be daring to go fast enough (60mph+) to go into the territory needed to do really huge ski jumps from a steep slope without needing a ramp. This will then, therefore, trailblaze the path to wingsuit landing on a slope without parachute.... (special skiis, custom made stuff, GPS gear, feat-engineering, Red Bull sponsorship, etc).

Allow progressive gear changes/adjustments
Obviously, you can call off/abort training at any point when things start to feel too risky, until gear adjustments are made (wingsuit, skiis, ski boots, bindings, helmet, knee/shoulder pads, neck braces, etc), and then resume training. I think that we really don't know what final gear is needed for actual wingsuit takeoff/landing on slopes, until people begin skiing down slopes while wearing a wingsuit.

The Daredevil Factor: Strive to eliminate untrainable territory
Once the extreme skiiers become proficient at doing big hops (liftoff from a ski slope), say 100, 200 and possibly 300 meters approaching the ski-jump world record, then the question now becomes, what needs to be trained for before you can do the wingsuit landing from an airplane? Instead of a wingsuit landing from a wingsuit takeoff from the slope? The recent wingsuit landing by Gary on cardboard boxes, provides some very useful information on the ability for a human to control a wingsuit flight to a precise landing. But that's only one wingsuit landing. All the Wingsuit BASE jumpers, including Jeb's trailblazing, show excellent proximity flying that are possible, but all of this is at extremely high speeds (>100mph) rather than an intent to land (50mph or less). You need to train through this overlap, and presumably, this will be via practice skydives at high altitudes and GPS tracks, some of which advice may be gained from people who have dreamed (or done!) a wingsuit landing without a parachute.

Now, the bigger risk is probably the skydive practice portion, if you're going to the next step (wingsuit landing on a slope from a skydive -- without deploying a parachute). Special emergency release mechanism becomes a much more risky endeavour -- due to the known BASE deaths, obviously. But it appears the wingsuit BASE jumpers and ski BASE jumpers are blazing that trail (for ski-release techniques), and eventually enough knowledge may start to exist where there's a relatively safe release mechanism (for skydive practice situations, to be able to release skiis before deploying parachute), although they're often using cheaper/heavier skiis than expensive ski-jumping skiis or racing skiis that one needs to practice keeping on for longer periods while flying wingsuit, and probably need to practice angling them ski-jumper style to make the skiis aerodynamically support your flight (such as this)

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It would be something that needs to be trailblazed. Practice wingsuit landings would have very low deployments, much like Gary did very low pulls during practice. Doing a stand deployment would be rather dangerous here; as that would speed up descent.

It would probably be the most dangerous territory of the learning/training for a wingsuit landing on a ski slope -- the emergency/practice low deployments while wearing skiis, the jettison procedure (if any).

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If something travels fast enough, it is likely to "take-off":
http://www.youtube.com/watch?v=O9iP_H0MnPE


I think what we should really look at here is the potential for a wingsuit landing on ski's without a parachute.
The trick would be flying with the ski's on, but I'll bet $100 bucks it is possible and very likely to see in the future.

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DSE -- Alas, not yet. I've got experience in ski/racing rather than wingsuiting. A little 'play' freestyle (not professionally), not just moguls, even though I used to a lot of frequent double-black diamonds back for the 90's and early 00's. Enough to know what airtime on skis mean, at least back in the day, launching myself completely into the air from a small freestyle snow slope, though I don't do somersaults. Some times, the aerial park too (now often called snowboard parks) and stuff.
...Note: Before you compose your response, remember it is easy to deduce that can wear a costume (which just happens to be a wingsuit) while going under 10mph on a shallow kiddie slope -- it's too slow to fly. A wingsuit is just essentially a costume while skiing on kiddie slope at under 10mph; The *point* is that it is very easy to see that _risk_escalation_ is very gradual and controllable -- i.e. 10mph-15mph-20mph-25mph-30mph-etc -- up to some specific point. It is possible to do just for kicks because it's virtually zero risk at 10mph anyway. Maybe it will add 0.1 second of airtime from a freestyle ramp even at just 20mph, while looking comedic and silly. Then at some speed X, maybe even as low as 30mph, we start to get into serious territory that starts providing useful research for wingsuit takeoff and/or landing endeavours.... Anyway, virtually anybody can ski on kiddie slopes regardless of whatever they are wearing, as long as they have sufficient balance and can see the slope ahead. The real risk/skills go when you can escalate to some speed such as X mph, of which presumably highly experienced wingsuit pilots would be able to go. The question is can these speeds be fast enough for wingsuit takeoff - and I think the answer is yes (which is also the point of this thread of discussion).

P.S. I'd also love to hear from other skiiers of your opinions. (more than a tourist skiier, even if you don't have professional experience, i.e. just being part of a weekly school skiing group/team/club, etc.)

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maxtreme -- I posted that link sometime ago in some of my other posts in the past. Andreas Küttel's wingsuit ski jump is potentially useful research, and it would be nice to contact Andreas to discuss with him. It was commented to allow the same jump distance at lower launch velocity -- so it did add airtime (which can be fractions of second) for a specific launch velocity.

On a similiar vein, Colm in the basejumper.com forum made this reply:
Quote

I was talking to a local olympic ski jumper a while back, about exactly this.

According to him, ski jumpers are essentially in a terminal, unaccelerated track, shortly after they depart the ramp. Given a ski slope of arbitrary length, the jumper could travel an arbitrary distance through the air, and land safely. The competition rules intentionally limit the aerodynamics of the skis to prevent people from going TOO far, ensuring it is more about your body flying than what kind of technology you strap to your feet. Practically speaking, the ultimate limit is just preparing a long-enough slope.

He made it sound like they are trackers that use skis instead of parachutes to land. I don't know anything about his sport so for all I know it was a load of crap. But he was a verified olympian so he might know a thing or two about ski jumping.

Although this is second-hand info -- from looking at the pictures of ski jumping from Merriam-Webster, it would appear that this Olympian is probably right. The wingsuit adds other variables, but it is worth researching, as wingsuit instructors say that tracking knowledge helps in learning how to wingsuit.

Almost tempting enough for me to try to learn ski jumping from a real ski ramp, partially to see how my tracking skills translate into ski jumping. (i.e. does being a good tracker, allow you to become a better ski jumper sooner? Very valid question.) Though, the ski jump equipment is quite expensive, and it's another entire hobby into itself, even if just done semi-recreationally with rental gear or just basic gear. It would be a low entry bar to skiiers with sufficient experience -- There are ski jump classes held at ski resorts from time to time, and it does give WAY more airtime than just leaping off that small ramp at the aerial/snowboard park on the slopes, even if not approaching olympic jumping. I wouldn't mind sharing my research, even though I would never do such daredevil feats. Alas, my location (Toronto) now puts me a bit far from the slopes that provide skijump lessons. But the entry bar is not that high especially if you're already an experienced alpine skiier that already enjoys going fast on black-diamond slopes. It does gets progressively more expensive/ambitious from there.

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they are definitely tracking off the ski jump, you can even see the tail 'wobbles' and potato chipping on slightly botched attempts like people learning tracking. Its very similar physics. I bet if you got enough speed and could collapse the wingsuit well enough and then open it up, then you could have a very long glide. If the slope continued long enough you could touch down (here is where your gradient learning process would come into play because the touchdown would ideally be slow over the course of a good long stretch of the slope).

its an exciting idea man! I have zero skiing experience and very little wingsuiting so I will sit back and watch :)

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oh yes I'm quite aware of ski-base...I believe it is a step up though to do WS ski-base :D

even that has been done though...whats left for the ego to feed on once all of these feats are accomplished? I'm sure somebody will think up even more ego-driven behavior:ph34r:



the people who paved the road for BASE jumping as you and i know it nowadays were called pioneers, not egomaniacs.............

well there may have been some ego involved, who knows, but people who push new limits in my opinion arent always doing it for fame/glory, they are just thinking way ahead outside the box.
gravity brings me down.........

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