Date: 28 Feb 93 02:41:08 GMT From: jeffy@syrinx.umd.edu (Jeffrey C. Burka) Message-ID: <18716@umd5.umd.edu> Organization: University of Maryland at College Park Subject: Ooooh! Sledding! We had a semi-decent snow here in DC yesterday, so today I did what any sensible kiter would do--grabbed my quadirfoil and the wonderful flexible flyer that was my dad's back in the early 50's and was passed onto my brother and I when we were kids. This sled is a true classic. I've been 'skiing' on my feet (and butt) on sand before, but the sledding was a _completely_ different experience, and a real trip! The sled is quite steerable, and like a buggy, it was quie convenient to sit at the rear of the sled and steer with my feet whilst holding the kite lines. I was amazed at how little pressure it actually took to get moving; I was only flying a Q-25, and the wind really wasn't even that strong--maybe 5-7 mph. By the end of the afternoon, I even managed to sled _up_ an admittedly shallow hill! But now I have questions for folks who've gone buggying or enjoyed other related forms of kite traction. I had a lot of problems with keeping the kite filled--it was quite common for me to overtake the kite and then start to slow down before it was pulling hard enough again to get me back up to speed. The most obviousl solution to this was to steer at an angle to the wind, and this _did_ work, at least to some extent. Perhaps it would have worked better if I'd had more wind. I was having lots of problems figuring out where to position the kite within the window in order to get myself to move in a particular direction with respect to the wind. Kite traction like this is very different from sailing, and yet I suspect it can be almost as complex (allowing for the simplification due to only having one 'sail' to worry about, and not the interaction between multiples...). So, anybody have any suggestions for things to try, proven techniques? Is it possible to actually tack against the wind? I was able to move at 180 degrees to the wind, but nothing beyond that. Perhaps it would have been easier if I had a kite that pulled harder at the edges of the window (ie a peel). What's Peter Lynn's pamphlet on the subject like? Worthwhile reading? Or does it mostly glorify the peel/buggy? Unfortunately, my current mode of transport depends on snow, and DC doesn't get all that much. With my luck, I won't get another chance to try this 'til next winter. Today convinced me, though, that I really, *really* want to get a buggy so I won't have to worry about the terrain as much. Well, someday I'll be able to afford one... This is *fun*! Jeff (who heartily recommends getting dragged around a field by large soft objects with many strings hanging from them) -- |Jeffrey C. Burka | "Fairies are the perfect people to do this | |(suffering Bad Grammar) | sort of work. Biologically, their upper | |jeffy@syrinx.umd.edu | bodies are strong enough to wield a pickaxe...." | = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: 28 Feb 93 18:08:31 GMT From: andrew@tug.com (Andrew Beattie) Message-ID: Organization: Negligible. Subject: Re: Ooooh! Sledding! In article <18716@umd5.umd.edu> jeffy@syrinx.umd.edu (Jeffrey C. Burka) writes: >I had a lot of problems with keeping the >kite filled--it was quite common for me to overtake the kite and then >start to slow down before it was pulling hard enough again to get me >back up to speed. This is the first lesson. The kite needs *apparent* wind in order to fly. When you are getting dragged down-wind on your bum, your bumb provides sufficient friction to be able to maintain the speed of the entire rig to something significantly below wind speed, so the kite keeps flying. If you sit your but on some efficient friction-reducing system (buggy/skis/sledge), then the only thing of any significance pulling against the kite is your inertia. Once the kite has overcome this, the system will find it's self travelling downwind at approx wind speed and the kite will fall out of the sky. With this system, doing downwind becomes (somewhat paradoxically) the most difficult course. On a buggy, the best speeds are reached at about 75 degrees off the wind direction. Unfortunately, getting started at that sort of angle is rather difficult. On a buggy, I find it best to start off facing down-wind for just long enough to overcome my (not insignificant) inertia, and then very quickly turn off to the side and try to develop speed. The buggy can turn on a dime and has very little rolling resistance, but a sledge can only be turned by applying a braking force, this may be a significant drawback. A sledge with steerable runners may help a lot. Once underway, you spend a lot of time concentrating on steering. If the kite goes too far in front of you, you will drive into it, stalling it. To counteract this, you steer upwind (much as you would run upwind to avoid a stall). When it catches the wind, you steer more downwind, to get the best acceleration from the pull. In the end, where you steer is just as important as where you fly, so you may find it difficult to progress much further without developing a sledge for the purpose. >What's Peter Lynn's pamphlet on the subject like? Worthwhile >reading? Or does it mostly glorify the peel/buggy? Peter's pamphlet is basically a large FAQ on Peels, buggys and kite sailers. It makes interesting reading. Next time I talk to him, I'll ask for permission to post it. Andrew -- andrew@tug.com