Soft Kites—George Webster

Page 6 The Kiteflier, Issue 102 Soft Kites—George Webster Section 1 years for lifting loads such as timber in isolated The first article I wrote about kites dealt with sites. Jalbert developed it as a response to the Deltas, which were identified as —one of the kites bending of the spars of large kites which affected which have come to us from 1948/63, that their performance. The Kytoon is a snub-nosed amazingly fertile period for kites in America.“ The gas-inflated balloon with two horizontal and two others are sled kites (my second article) and now vertical planes at the rear. The horizontals pro- soft kites (or inflatable kites). I left soft kites un- vide additional lift which helps to reduce a teth- til last largely because I know least about them ered balloon‘s tendency to be blown down in and don‘t fly them all that often. I‘ve never anything above a medium wind. The vertical made one and know far less about the practical fins give directional stability (see Pelham, p87). problems of making and flying large soft kites– It is worth nothing that in 1909 the airship even though I spend several weekends a year —Baby“ which was designed and constructed at near to some of the leading designers, fliers and Farnborough has horizontal fins and a single ver- their kites. tical fin. Overall it was a broadly similar shape although the fins were proportionately smaller. —Soft Kites“ as a kite type are different to deal It used hydrogen to inflate bag and fins–unlike with, compared to say Deltas, as we are consid- the Kytoon‘s single skinned fin. The aim was to ering a relatively small number of designs mostly provide directional stability (P.B. Walker —Early by an international group of highly talented de- Aircraft at Farnborough Vol. 1“ Macdonalds signers/makers, rather than by adventurous club 1971). It was a recognisable ancestor to Second fliers. World War Barrage Balloons. So after a look at some definitions, section 2 is a At least two toy kites have been marketed which chronology and section 3 examines design fea- used inflation by mouth to produce the flying tures. Thanks to Gill and Jon (and Tara for typ- shape (a fat Eddy). One, the Stewkie Glida–kite ing) for dealing with old-fashioned paper. Photos is lost in the mists of the 70‘s, the other the are all by G. Webster except: KSGB Numbers 8, American Puffer kite (with an ingenious straw 10, 15, 17 and 29, Mark Bowlas numbers 13, 14, and simple valve inflation system) was still being 21, 22 and 24 made in ”97 (Photo 2). Note The absence of spars is not by itself the mark of This is nearly the end of the series of articles. a soft kite. Back in 1948 Francis Rogallo pat- For the next issue I hope to have a short article ented his flexible kite (see Pelham p83 and my on —Bits and Bobs“ together with a note on how article on Deltas) where the bridles determined they all fit into a book. Every comment and criti- the curve of the wing (i.e. no spars but no infla- cism so far has been valuable. tion). First sold by the Rogallos in 1949, the original design was produced commercially as a Section 1 toy for many years from ”54–I just can‘t find a The fundamental soft kite is a parafoil (photo 1) photo of my 80‘s red mylar version. in which there are no spars and the upper and lower surfaces of the skin of the kite are con- Rogallo in his ”48 patent application foresaw that nected by risers. There is a gap along the lead- a stiffened keel or spars might be needed in a ing edge through which wind enters and by pres- large kite–he mentioned that they might be in- sure inflates and holds the kite‘s designed shape. flatable. So Rogallo could argue (see article in The shape flies i.e. produces lift greater than American Kite Fall ”88) that the key invention weight plus drag. Such kites have been called was the idea of the flexible wing and in that descriptively —ram-air“. The principles of ram-air sense Jalbert‘s inflated wing section followed Ro- inflation, not necessarily from the leading edge, gallo‘s invention. Hopefully Tal Streeter‘s new and the kite‘s flying surfaces being held in posi- book will help on this. tion by internal fabric risers (or later by cords) are common to nearly all soft kites. Ram-air tubes to replace the spars in the sled design were produced–Ed Gravel‘s Bullet of ”73 There have been some kites which do not use is a forerunner. I have memories of monstrous ram-air for inflation. Of most practical impor- Eddys being produced for record–breaking pur- tance has been the Kytoon developed over 60 poses in the USA which used pre-inflated (i.e. years ago by Domina Jalbert and used for many not ram-air) spars. But most see Rogallo‘s role The Kiteflier, Issue 102 Page 7 Soft Kites—George Webster 3hoto 1. Photo 2 Photo 3 Photo 8B Photo 4 Photo 7 Photo 8A Photo 5 Photo 6 Photo 10 Photo 7A Photo 9 Page 8 The Kiteflier, Issue 102 Soft Kites—George Webster as being the direct producer of the hang glider Flowform (photo 6) with its distinctive cut away and being important in the development of the trailing edge is still used at kite festivals as a Delta–all using the single skin canopy. Jalbert is lifter. It uses a thicker section chord than a typi- the father of ram-air parachutes and the modern cal parafoil with a much larger front edge intake soft kite. Photo 3 shows the first commercial linked with air exiting along the trailing edge. —toy“ kite, the J-7.5 of the ”70‘s. There are also holes both between risers (shared with some parafoil designs) and on the upper Designers have used ram-air combined with and lower skins to allow air movement in re- spears to great effect. Undoubtedly the leader in sponse to local changes in pressure. Claimed to this type of kite has been Martin Lester. His be better in fluctuating winds it has the practical shark of ”83 is still a wonderful wriggling creation advantage of requiring fewer bridles. when correctly sparred (photo 4 is an artistic 1978–Richard Lewis produces the flexible shot). The bird kite article shows his goose. I pocket kite. managed to get a pre ‘88 space shuttle at a re- 1981–Jalbert takes unsuccessful action against cent auction (photo 5). Few other designers/ the Sutton Flowform on the grounds that it in- craft men seem to have used this combination fringes his patent. although in recent years there have been —toy“ 1981–The Ferrari Ram (photo 7) is advertised kites using air to give a 3D body to aircraft and in the UK. Still being made, it uses ram-air to birds. stiffen a series of tubes–the bridling makes it clear that this a type of sled. One last look round before we get down to the 1981–Scheveningen œa Dutch team flies the chronology–have soft kites existed before or world‘s largest kite (50 ft, 550m2) - photo 7a elsewhere? Interestingly one of the candidates shows it at Scheveningen. for the earliest European kites (see article —An 1983–Martin Lester‘s Shark created, it is his Outline History of Kites in the West“) was a wind- signature kite and is still part of his logo. sock. I doubt whether it was designed with lift in 1987–Peter Lynn, a New Zealand designer hith- mind but perhaps the stubby dragon wings erto best known for his Tri-D box kites, takes up helped. Incidentally it is suggested that they had kite sailing using a steerable parafoil parachute fire in their mouths, which, with smoke, fright- given to him by the American John Walters. ened the enemy. Apart from the problem of fire- 1988–Martin Les- proofing, flames might have been very spectacu- ter‘s —Legs“ kite. lar as presumably air (and therefore flames) The origins of the flowed in and out of the mouth with changed in kite are Martin‘s wind conditions. I don‘t know of oriental designs response to the which used wind pressure to form a 3D shape œ advert on the back while whistles, hummers and mechanical devices page of The Kite- are of course common. flier, published by the Kite Society of Section 2–Chronology Great Britain, Jan ”88 (illustration 1930‘s–Domina Jalbert develops the Kytoon right, see also 1948–Francis Rogallo patents the —flexible kite“ www.aeolian.co. 1951–Rogallo writes in Ford Times–—If we uk). While Mar- could combine the shape of the supersonic air- tin‘s own legs plane with the unbreakable structure of the para- were widely seen chute, we would have a fine kite indeed!“ at the time, no 1964–Jalbert looks at his Beechcraft plane wing such kite existed. and decides to produce a soft cambered airfoil. This, his first to- He starts by removing the gas tank cover and tally soft kite was measuring his plane‘s wing chord. produced later in the year. Looking at the advert 1974–Steve Sutton, a parachutist, having seen it is obvious that a soft kite was not envisaged trials of the Jalbert parafoil in 1965, patents his and one wonders about the significance of the Flowform parachute, which in 1979 becomes the bridling.

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