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View Full Version : Uplift Lofting For Fun?


ricki
02-05-2010, 09:24 AM
I put this up not to endorse doing this sort of thing. You see it and naturally in some cases want to try it. Hey, if I am 10,000 ft. up a mountain, like on the L'Aiguille du Midi in Cham, I feel like jumping out into space over the valley most of the time but I don't do it! I am amazed that anyone would do this particularly experienced paragliders as claimed. Haven't these people ever had anything break (lines, bridles, harness hook, harness, kite tear, leading edge deflate, etc.), get backwinded, screw up ... over the water on kite gear? I've had dozens of such failures over 11 years myself. Anyway, bad idea using fragile, unreliable kite gear. Hang gliders, paragliders and sailplane pilots live for soarable conditions, have for decades, different story.

I put this up to illustrate uplift lofting. These guys insert their kite into the lift band or wind as it pops up over the dune. The lift band can develop pretty far to windward from the upward deflecting surface too. The kite sees this lift band and lifts the kiter right into it. Look at how far away from the dune he hits it, the rise in response, the bumps up, drops, etc.. Plenty of guys including a some deceased riders failed to maintain control when surprised by this phenomena. This could happen to you by accident, best to understand what causes it and how to avoid it (keep your kite out of the lift band and don't jump anywhere near it. It seems like it is a lot easier to be uplift lofted if you've already escape gravity in a jump, even a small one. Erik Eck just jumped over some lines on the ground, that was enough to send him up. Keep your kite low near shore get offshore and stay there until time to come in. Don't stand around on the beach, beach jump or otherwise insert your kite into a lift band as you might not do as well as the guys in the video. The outward conditions that lead to uplift lofting seem to be common. It isn't clear why accidents and incidents aren't more common, thankfully they are not however.


http://www.ssa.org/sport/images/ridge.jpg
Soaring lift band
From: http://www.ssa.org/

http://www.ov-10bronco.net/users/merlin/pix/flight/rc/slope_xsect.jpg
From: http://www.ov-10bronco.net/users/merlin/flight/slopesoar.htm
For kiters this should say, DON'T FLY HERE!

Another diagram showing condo soaring conditions for sailplane pilots. Note the dead air zone. The shape and dimensions of this zone depend on the geometry of the uplift, vertical surface, wind speed and other factors. If your kite is inserted in the dead air zone and stays there you may have no issues. Note that the lift zone develops to windward of the dead air zone. The goal is to keep your kite out of the lift band. They make other comments about the layout of the lift zone including:

"The lift area extends from the front face of the slope or obstruction, up roughly along its vertical face to an altitude of roughly twice its height, out to about that same distance in front (upwind). If the wind is coming in at an angle, this area will be extended farther towards the upwind side of the building.

There is an area of little or no real lift that I call the dead zone that is found close to the ground or beach, and also in the "corner" where the front of the obstruction meets the flat ground. For gently-sloping dunes or hills, there may be little or no dead zone. This is the area where the wind stagnates, while the rest of wind blows over it. It is usually not particularly dangerous, although if you forget that there is little lift here you can be fooled into flying yourself to a forced landing due to lack of lift. It can be useful however as a calm area for landing in or sitting in, somewhat shielded from the icy blast of a wintertime gale."

You can develop lift bands from dunes, mountains, slopes, buildings, walls, tree lines, etc.. The potential causes are common, uplift lofting less so. Do yourself a favor and study the video, lots of free info there. A man was uplift lofted and dropped head first on a dike many years ago, a man in Spain hit the roof of a building after being uplift when crossing the shore. Most kiters when they are lofted inland are uplifted lofted to a degree extending the distance of travel, perhaps increasing height substantially as well.

Again, misusing kite gear in this way is ill advised in the extreme. Use paragliding or hangliding gear which was purpose developed for it over decades, with tons of T&E, training, safety procedures and lots of dead and injured pilots building up to the current state of knowledge, training and gear. There is lots of redundancies, training and safety options to try to avoid problems and better manage them if problems occur. With kite gear, if something breaks, lines, bridles, harness hook, whatever, you have a good chance of slamming in hard.

LhwkV6OLWFM


The video was dedicated to a well known speed flier, Nicolas Kälin. Nicolas was tragically killed in a cross country paragliding flight on a small canopy near Murren, CH when he flew into a high tension power line. More at: http://www.speed-flying.com/discussions/speed-flying/fatal-powerlines-crash RIP Nicolas.

ricki
02-05-2010, 10:27 AM
How many folks have experienced uplift forces when your kite went into a lift band? I'm not asking about loftings, just the feeling of upward force when your kite floats into the upward flow? If you are jumping it doesn't look like it takes much to go up.

damion_dark
02-07-2010, 05:46 PM
That is a very dangerous thing to do.

damion_dark
02-10-2010, 01:09 PM
Here is another Darwin Award winner....



http://www.youtube.com/watch?v=hzOCEDm73tM

Thirdcoast Kiteman
02-18-2010, 09:07 AM
In our area, ridge soaring is very popular among hangliders, paragliders, and sail planes...I wouldn't use my kite gear to do it though. PG's have multiple redundant control lines, where as kiteboaring gear doesn't.

Also, you have to familiar and experienced with the terrain where you soar. Areas along the ridge that warm more readily produce rising air currents and can catch the inexperienced unprepared for the sudden lift.

There is some experience transfer between kiting and soaring, but it doesn't take a genius to know you should use the best and most appropriate gear available.

I subscribe to the old pilots saying, "there's old pilots and bold pilots, but there are no bold-old pilots."

ricki
02-18-2010, 10:00 PM
In our area, ridge soaring is very popular among hangliders, paragliders, and sail planes...I wouldn't use my kite gear to do it though. PG's have multiple redundant control lines, where as kiteboaring gear doesn't.

Also, you have to familiar and experienced with the terrain where you soar. Areas along the ridge that warm more readily produce rising air currents and can catch the inexperienced unprepared for the sudden lift.

There is some experience transfer between kiting and soaring, but it doesn't take a genius to know you should use the best and most appropriate gear available.

I subscribe to the old pilots saying, "there's old pilots and bold pilots, but there are no bold-old pilots."

Well said.

jetpack
02-19-2010, 09:04 AM
I subscribe to the old pilots saying, "there's old pilots and bold pilots, but there are no bold-old pilots."

As well as,

"Always better to be on the ground wishing you were in the air, than in the air wishing you were on the ground".