Date: Tue, 12 Oct 1993 22:37:28 -1000 From: micha@ekpux3.physik.uni-karlsruhe.de (Michael Schneider) Message-Id: <29geo8$td@nz12.rz.uni-karlsruhe.de> Organization: University of Karlsruhe, Germany Subject: flexi without spare hi kiters, i managed to fly my 6ft flexi without spare. therefore i sew some tabs to my bought flexi by hand and attached a bridle with 10 lines. i positioned this tabs about 1cm below the vent. after playing a little with the bridle the flexi comes up, but very low speed, very low pull and bad steering. before i start to sew my first selfmade one, i have some questions: is it possible to make a really good flying flexi without spare? if yes, where to put the tabs and which bridle type and linelength? btw: how to make an ultralight spare? they are very expensive in germany (60-70DM for a 6ft). thanks in advance, micha -- ================================================================== Michael Schneider Institut fuer Experimentelle Kernphysik der Universitaet Karlsruhe Engesserstr. 7(Physikhochhaus), 76128 Karlsruhe 1 micha@ekpux2.physik.uni-karlsruhe.de | BD14@DKAUNI2.BITNET ================================================================== = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Wed, 13 Oct 1993 03:20:47 -1000 From: jeffy@syrinx.umd.edu (Jeffrey C. Burka) Message-Id: <29gvbf$s1b@umd5.umd.edu> Organization: University of Maryland at College Park Subject: Re: flexi without spare In article <29geo8$td@nz12.rz.uni-karlsruhe.de> micha@ekpux3.physik.uni-karlsruhe.de (Michael Schneider) writes: >i managed to fly my 6ft flexi without spare. therefore i sew some >tabs to my bought flexi by hand and attached a bridle with 10 lines. >i positioned this tabs about 1cm below the vent. after playing a >little with the bridle the flexi comes up, but very low speed, >very low pull and bad steering. Nifty. Don't think I've seen anyone fly a sparless Flexi before. This not to say there aren't plenty of great sparless stunters out there... >before i start to sew my first selfmade one, i have some questions: >is it possible to make a really good flying flexi without spare? Depends on how you define "really good flying." You *won't* get a flexifoil without a spar. You *can* make something that flies much better than "passably" without a spar. >if yes, where to put the tabs and which bridle type and linelength? Rather than try to clone a Flexi and fly it without a spar, you'd be better off to get one of the plans for a sparless stunter. There are quite a few plans in publication now, including the Paraflex (Schimelpfennig, wasn't it?) (I've probably butchered the spelling of his name), the Booster (and derivatives Super Fly and Banana), and the Sputnik (Nop Velthuizen). In most of these cases, the kite has two or three bridle attachments between cells, allowing for adjustment of the kite's angle of attack (that's probably your biggest problem with the Flexifoil; I'd guess that the spar does a *lot* in adjusting the angle of attack since the kite is amazingly front-heavy). There are two common bridling techniques. One is just to gather the bridles on each half of the kite to a common point. The other is to run a long line that has each bridle line (or pair of) attached to it and then to attach your flying lines to either side of this main line (that description probably isn't doing you much good...). There are more complex bridles out there too. For instance, one of the best dual line soft kites is the Peel. It's optimized for power kiting and uses an amazingly complex interwoven bridle; for each point along the line >From leading to trailing edge, there's a pair of bridle lines, one to each side of the kite. This also allows for a reefing system (smoothing out the pull of the kite across the center of the window and in gusts) simply by attaching a bungee system to the bridle lines from the opposite side of the kite (thus, on the right-hand tow point, the bridle lines that head off to the left of the kite are attached via a piece of bungee). There are also great soft quadlined kites. Perhaps the simplest quad 'foil I've seen was 2 J-7.5 parafoils that were sewn together on one side. Lines were added to each trailing edge for the extra lines. The bridling still needed work when I flew the kite, but it *definitely* flew and was fun. The commercial quads (and for that matter Kite Innovations earlier dual line parafoil) had keels only on the outside edges and use a lot of bridle lines across the body of the kite to approximate the distribution of pull across the sail that you'd normally get from the keels. >btw: how to make an ultralight spare? they are very expensive in >germany (60-70DM for a 6ft). Geez. Sounds like it'd be cheaper to have one airmailed from the US! 6' Ultraflexes here tend to cost ~$25! I know one fellow who made his own Ultraflex. The Ultraflex is comprised of 3 pieces: two fiberglass and one Easton 4-18 in the center. The guy I know who made his bought large sticks of fiberglass and then sanded them down on a power sander 'til they were about as flexible as the real Ultraflex spars. Seemed like a lot of work to me considering how cheap the spars are... Jeff -- |Jeffrey C. Burka | "When I look in the mirror, I see a little clearer/ | |SAFH Lite [tm] | I am what I am and you are you too./ Do you like | |jeffy@syrinx.umd.edu | what you see? Do you like yourself?" --N. Cherry | = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Wed, 13 Oct 1993 07:37:58 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: flexi without spare jeffy@syrinx.umd.edu (Jeffrey C. Burka) writes: >micha@ekpux3.physik.uni-karlsruhe.de (Michael Schneider) writes: >>i managed to fly my 6ft flexi without spar. > >In most of these cases, the kite has two or three bridle attachments >between cells, allowing for adjustment of the kite's angle of attack >(that's probably your biggest problem with the Flexifoil; I'd guess that >the spar does a *lot* in adjusting the angle of attack since the >kite is amazingly front-heavy). Hmm... The way that a flexi manages to fly from a spar in the leading edge is that it generates a lot of lift near the front (a force that tends to rotate the wing round the spar) and a little *reverse* lift near the rear. (look at a rib some time, it has a reverse aerofoil towards the rear!) The lesser, reverse force has much more leaverage, to keep the thing flying at the right angle. The Flexi is patented. The idea of a soft flexi which is bridled close to the leading edge is also protected by patent. >There are more complex bridles out there too. For instance, one of the >best dual line soft kites is the Peel. It's optimized for power kiting and >uses an amazingly complex interwoven bridle; for each point along the line >from leading to trailing edge, there's a pair of bridle lines, one to each >side of the kite. This also allows for a reefing system (smoothing out the >pull of the kite across the center of the window and in gusts) simply by >attaching a bungee system to the bridle lines from the opposite side of the >kite (thus, on the right-hand tow point, the bridle lines that head off to >the left of the kite are attached via a piece of bungee). Close. The (protected) reefing and (protected) cross bridle systems are something like this: Every other rib is re-inforced to take 4 lines. These 4 lines come down to one point (point "A"). From this point, there is one line to the left flying line attatchment point ("B") and one to the right. The reefing system basically attatches every other bridle line through a bungee (at "B"). This means that when the power builds up the lines to every *other* point "A" stretches and the canopy concertinas, reducing it's area. >Geez. Sounds like it'd be cheaper to have one airmailed from the US! 6' >Ultraflexes here tend to cost ~$25! Sheesh! My 10' Ultraflex cost me UKP60! Andrew -- Work: gaffer@rec.com Phone: +44 793 614 110 Fax: +44 793 614 297 Play: andrew@tug.com Phone: +44 256 464 912 Car: +44 831 527 614 Interested in kite traction? mail kites@tug.com = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Thu, 14 Oct 1993 09:16:05 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: flexi without spare ajb@oasis.icl.co.uk (Adam Buckley) writes: >Andrew Beattie (andrew@tug.com) wrote: >: >Ultraflexes here tend to cost ~$25! >: Sheesh! My 10' Ultraflex cost me UKP60! >What's the cheapest way to buy another two Super10 Flexifoils ? Price is the same, UKP 125 everywhere in the UK. Flashing a membership card will usualy get you 10 Be very pleased with yourself if you do better than that. Flexifoil don't sell to trader's who don't have a shop, so don't expect to find a fly-by-night trader selling them off cheap. Flexies are significantly more expensive abroad. Buying from a UK trader may well be worth looking at, wherever you live. Andrew -- Work: gaffer@rec.com Phone: +44 793 614 110 Fax: +44 793 614 297 Play: andrew@tug.com Phone: +44 256 464 912 Car: +44 831 527 614 Interested in kite traction? mail kites@tug.com = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Thu, 14 Oct 1993 05:09:11 -1000 From: ajb@oasis.icl.co.uk (Adam Buckley) Message-Id: Organization: ICL, Bracknell, UK Subject: Re: flexi without spare Andrew Beattie (andrew@tug.com) wrote: : >Ultraflexes here tend to cost ~$25! : Sheesh! My 10' Ultraflex cost me UKP60! What's the cheapest way to buy another two Super10 Flexifoils ? Adam Buckley = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Thu, 14 Oct 1993 15:15:54 -1000 From: jeffy@syrinx.umd.edu (Jeffrey C. Burka) Message-Id: <29ktka$bc8@umd5.umd.edu> Organization: University of Maryland at College Park Subject: Re: flexi without spare In article andrew@tug.com (Andrew Beattie) writes: >Price is the same, UKP 125 everywhere in the UK. Yeesh! That's *cheap*. SO WHY ARE YOUR ULTRAFLEXES SO EXPENSIVE? ;-) Jeff -- |Jeffrey C. Burka | "When I look in the mirror, I see a little clearer/ | |SAFH Lite [tm] | I am what I am and you are you too./ Do you like | |jeffy@syrinx.umd.edu | what you see? Do you like yourself?" --N. Cherry | = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Fri, 15 Oct 1993 05:57:58 -1000 From: ajb@oasis.icl.co.uk (Adam Buckley) Message-Id: Organization: ICL, Bracknell, UK Subject: Re: flexi without spare Andrew Beattie (andrew@tug.com) wrote: : ajb@oasis.icl.co.uk (Adam Buckley) writes: : >Andrew Beattie (andrew@tug.com) wrote: : >: >Ultraflexes here tend to cost ~$25! : >: Sheesh! My 10' Ultraflex cost me UKP60! : >What's the cheapest way to buy another two Super10 Flexifoils ? : Price is the same, UKP 125 everywhere in the UK. Flashing a membership I got mine in the Channel Islands for UKP100 with free lines. No VAT of course. Maybe I should go back there. Adam = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 18 Oct 1993 09:00:07 -1000 From: mark@murder.demon.co.uk (Mark de Roussier) Message-Id: <750996007snx@murder.demon.co.uk> Organization: damage Subject: Re: flexi without spare In article ajb@oasis.icl.co.uk (Adam Buckley) writes: > Andrew Beattie (andrew@tug.com) wrote: > : ajb@oasis.icl.co.uk (Adam Buckley) writes: > : >Andrew Beattie (andrew@tug.com) wrote: > : >: >Ultraflexes here tend to cost ~$25! > : >: Sheesh! My 10' Ultraflex cost me UKP60! > : >What's the cheapest way to buy another two Super10 Flexifoils ? > > : Price is the same, UKP 125 everywhere in the UK. Flashing a membership > > I got mine in the Channel Islands for UKP100 with free lines. No VAT of > course. Maybe I should go back there. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Hey, hire a mini - bus ! An artic !:) Ooops - I guess a ferry/plane might have to be involved somewhere along the way :(. Mark de Roussier ************************************ Final thoughts, as breath is taken, Fall to rhythm, and the Edge of pure obsession, Resting in that wind blown cradle, Nothing moves, the world is still... ************************************ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =