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Brad wrote:
I was browsing thru one of the Yahoo glider N.G.'s today and read where the World Class design may get ressurected. That got me to thinking: What would the ideal recreational next generation sailplane sailplane look like? I imagine it won't look much different from what we are seeing now in terms of slender body shapes with sexy wingtip treatments. And with the price of carbon fiber coming down, the expanding growth of the composites industry and the rising use and availability of CNC machining, it seems that there might be a niche market for a good performing, lightweight sailplane that could be tailored for the recreational market. This subject has beaten the dead horse into dog food and baseballs by now. More Purina than home runs I'm afraid ;-) Nevertheless... ....We know what *shape* we want, that's pretty easy. What ever *It* is, it should be shaped similarly to a Discus, LS-8, ASW-24 etc. Some solid handling, 15 m span, flapless (I like flaps, but a volksglider should be flapless IMHO), retractable gear, known quantity. What would make such a beast unique, and affordable, is the way that shape gets produced. I suspect the prepreg technique used in the Sparrowhawk is in the right direction. Farm out fabric cutting to someone who could laser cut many ships worth of cloth when the price is low? Also, with all the wind farms going up around the world, the technology involved in manufacturing big composite wings should be improving rapidly. Perhaps wings with a significant portion of constant cord/profile (half span?) with a mass produced, extruded spar that is cut into a segment for each wing (diverges from the Discus-esque shape but at what performance cost?) could simplify production. Posters here have said that a significant amount of the labor that goes into the manufacture of gliders is in the sanding and polishing to get a glassy smooth surface. On behalf of all the pilots who've happily flown 30 year old gliders with crappy finishes "Who cares?". If I could get a solid performing glider with a dull white finish at 2/3 the price, that's fine with me. Perhaps some decrease in surface waviness is realized in the process, but modern gliders shrink significantly over the first few years anyway, negating some of the benefit, so why pay for sanding twice? My $ 0.02 (On sale half price tomorrow only!) Shawn P.S. Sorry that this is so disjointed, dinner's ready :-) |
#2
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Hi Shawn,
Here are some replies to your excellent post: This subject has beaten the dead horse into dog food and baseballs by now. *More Purina than home runs I'm afraid ;-) Nevertheless... Agree..................but the more water that goes over a ducks back, eventually some water soaks in................I hope the same can be said here, in a metaphorical sense......... ![]() ...We know what *shape* we want, that's pretty easy. *What ever *It* is, it should be shaped similarly to a Discus, LS-8, ASW-24 etc. Working on the shapes now, that's pretty easy with modern CAD programs. 15 m span, Agree completely, maybe even leave room for a 17m extension at the tip. flapless (I like flaps, but a volksglider should be flapless IMHO), Flaps would be easy enough to do, I think, but I would not rule out your suggestion either, after all, it is a Volksglider. retractable gear, known quantity. Agree. What would make such a beast unique, and affordable, is the way that shape gets produced. Have that covered I suspect the prepreg technique used in the Sparrowhawk is in the right direction. * Here is disagree. Greg is fortunate to have use of the huge autoclave at the Lancair/Columbia factory, I think. Although Out of Autoclave could be done with the right tooling and materials. But I think wet layup and vacuum bagging would be cheaper. Farm out fabric cutting to someone who could laser cut many ships worth of cloth when the price is low? Good idea............I would guess that this would depend on the number of ships to be produced. *Also, with all the wind farms going up around the world, the technology involved in manufacturing big composite wings should be improving rapidly. *Perhaps wings with a significant portion of constant cord/profile (half span?) with a mass produced, extruded spar that is cut into a segment for each wing (diverges from the Discus-esque shape but at what performance cost?) could simplify production. I would make a wing with an LS-3 planform. Carbon/H-60 foam core. Graphlite spar caps. Posters here have said that a significant amount of the labor that goes into the manufacture of gliders is in the sanding and polishing to get a glassy smooth surface. *On behalf of all the pilots who've happily flown 30 year old gliders with crappy finishes *"Who cares?". *If I could get a solid performing glider with a dull white finish at 2/3 the price, that's fine with me. *Perhaps some decrease in surface waviness is realized in the process, but modern gliders shrink significantly over the first few years anyway, negating some of the benefit, so why pay for sanding twice? Agree................throw a sandable primer coat into the molds and have the buyer do the finishing to their standards/needs/requirements. My $ 0.02 (On sale half price tomorrow only!) Thanks! Brad P.S. *Sorry that this is so disjointed, dinner's ready *:-) mines on hold................had to take a dog to the vets............: ( |
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Brad wrote:
Hi Shawn, snip I suspect the prepreg technique used in the Sparrowhawk is in the right direction. Here is disagree. Greg is fortunate to have use of the huge autoclave at the Lancair/Columbia factory, I think. Although Out of Autoclave could be done with the right tooling and materials. But I think wet layup and vacuum bagging would be cheaper. Agreed, I'm thinking to make a big dent in glider price (I'm in the depressed Dollar US, and I *won't* buy a Chinese glider) the method of manufacturing will have to be very different. More composite manufacturers making aircraft and wind turbine parts might make more autoclave space available. Heated molds are a possibility (read about it on a wind turbine site). I suspect new composite technology is coming along all the time (not my field). A fuselage formed by winding carbon fiber tape around a male mold seems pretty straightforward, spars too. I don't know if a wing could be made with a precise enough profile in this way, interesting thought though. I know there are specialty companies applying all sorts of new composite technology. Farming out rather than investing in house might make a lot of sense in the small numbers world of sailplane manufacturing. Save on tooling, benefit from the sub's economy of scale. Certainly not business as usual in the glider industry. snip P.S. Sorry that this is so disjointed, dinner's ready :-) mines on hold.......had to take a dog to the vets...... Hope the pup's OK. Had to do this three weeks and four stitches to the leg ago. Shawn |
#4
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Shawn wrote:
Brad wrote: Here is disagree. Greg is fortunate to have use of the huge autoclave at the Lancair/Columbia factory, I think. Although Out of Autoclave could be done with the right tooling and materials. But I think wet layup and vacuum bagging would be cheaper. Agreed, I'm thinking to make a big dent in glider price (I'm in the depressed Dollar US, and I *won't* buy a Chinese glider) the method of manufacturing will have to be very different. More composite manufacturers making aircraft and wind turbine parts might make more autoclave space available. Heated molds are a possibility (read about it on a wind turbine site). I suspect new composite technology is coming along all the time (not my field). A fuselage formed by winding carbon fiber tape around a male mold seems pretty straightforward, spars too. I don't know if a wing could be made with a precise enough profile in this way, interesting thought though. I know there are specialty companies applying all sorts of new composite technology. Farming out rather than investing in house might make a lot of sense in the small numbers world of sailplane manufacturing. Save on tooling, benefit from the sub's economy of scale. Certainly not business as usual in the glider industry. The Edgley EA9 was primarily constructed from CNC laser cut composite honeycomb panels, wrapped around and bonded to ribs and formers. Clearly this can't produce a super accurate wing profile, but might result in some reduction in the labor required to produce wing or fuselage parts. If I remember correctly, the EA9 kit was fairly inexpensive, and could be built in a few hundred hours. Marketing a kit built single seat ASK-18 look-alike during the 90s was clearly a mistake. I suspect there would be a bit more of a market for a factory built US LSA two seat glider, if the price could be kept closer to $50K than $100K... Marc |
#5
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Marc Ramsey wrote:
Shawn wrote: Brad wrote: Here is disagree. Greg is fortunate to have use of the huge autoclave at the Lancair/Columbia factory, I think. Although Out of Autoclave could be done with the right tooling and materials. But I think wet layup and vacuum bagging would be cheaper. Agreed, I'm thinking to make a big dent in glider price (I'm in the depressed Dollar US, and I *won't* buy a Chinese glider) the method of manufacturing will have to be very different. More composite manufacturers making aircraft and wind turbine parts might make more autoclave space available. Heated molds are a possibility (read about it on a wind turbine site). I suspect new composite technology is coming along all the time (not my field). A fuselage formed by winding carbon fiber tape around a male mold seems pretty straightforward, spars too. I don't know if a wing could be made with a precise enough profile in this way, interesting thought though. I know there are specialty companies applying all sorts of new composite technology. Farming out rather than investing in house might make a lot of sense in the small numbers world of sailplane manufacturing. Save on tooling, benefit from the sub's economy of scale. Certainly not business as usual in the glider industry. The Edgley EA9 was primarily constructed from CNC laser cut composite honeycomb panels, wrapped around and bonded to ribs and formers. Clearly this can't produce a super accurate wing profile, but might result in some reduction in the labor required to produce wing or fuselage parts. Different altogether than winding tape around a mold. Also the EA9 was another exercise in butt ugly glider. Maybe that was just the green color :-p From this site: http://www.advancedcompositetraders.com/html/news.html Fiber placement and tape laying The fiber placement process automatically places multiple individual pre-impregnated tows onto a mandrel at high speed, using a numerically controlled placement head to dispense, clamp, cut and restart each tow during placement. Minimum cut length (the shortest tow length a machine can lay down) is the essential ply-shape determinant. The fiber placement heads can be attached to a 5-axis gantry or retrofitted to a filament winder or delivered as a turnkey custom system. Machines are available with dual mandrel stations to increase productivity. Advantages of fiber place~ ment fabrication include speed, reduced material scrap and labor costs, parts consolidation and improved part-to-part uniformity. The process is employed when producing large thermoset parts with complex shapes. Tape laying is an even speedier auto~ mated process in which prepregged tape, rather than single tows, is laid down con~ continuously to form parts. It is often used for parts with highly complex contours or angles. Tape lay up is versatile, allowing breaks in the process and easy direction changes. Capital expenditures for computer-driven, automated equipment can be significant, however. Suitable for both simple and complex parts, tape laying is the current method of choice for wing skin panels on the F-22 Raptor fighter jet. As I said before, this would be farmed out to a subcontractor who's already made the capital investment, unless the glider world sees really amazing growth. Shawn |
#6
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There are many well known ways to reduce the manufacturing costs of
composite structures. It just takes sophisticated tooling. The problem with gliders is that no one design has ever been made in sufficient numbers to justify the up-front costs of that tooling. The result is hand made, low production rate gliders and high unit costs. The big advantage of a "one-design" is not so much in leveling the playing field in contests, it's the hope that the design can be made in large enough numbers for a manufacturer to justify the costs of advanced manufacturing methods. The wingspan or whether a glider has flaps or retractable gear doesn't matter very much if the numbers are there. The solution doesn't lie in designing a small, simple glider, it lies in a design that satisfies a large number of buyers. Find that design, build it in large numbers and the unit costs can be very low. For example, how many buyers are there for a brand new LS-4 selling for $25,000 - quite a few I expect. So, how do you get it started? Don't start a new competition class, re-jigger an old one. For example, take the sports/club class and provide a handicap advantage for the "one-design". Any pilot can still fly whatever but the new design will have an advantage built into its handicap. Over time, the population of the new design will increase until a real "one-design" class emerges. If the design is popular enough and the rules guarantee the handicap advantage is permanent, the manufacturer may commit to the tooling and processes that drive down the cost. Of course, you have to have a commitment from the manufacturer that the price will follow costs down. Maybe the handicap advantage is only available to gliders whose price is less than a set figure. Bill Daniels "Shawn" wrote in message . .. Brad wrote: Hi Shawn, snip I suspect the prepreg technique used in the Sparrowhawk is in the right direction. Here is disagree. Greg is fortunate to have use of the huge autoclave at the Lancair/Columbia factory, I think. Although Out of Autoclave could be done with the right tooling and materials. But I think wet layup and vacuum bagging would be cheaper. Agreed, I'm thinking to make a big dent in glider price (I'm in the depressed Dollar US, and I *won't* buy a Chinese glider) the method of manufacturing will have to be very different. More composite manufacturers making aircraft and wind turbine parts might make more autoclave space available. Heated molds are a possibility (read about it on a wind turbine site). I suspect new composite technology is coming along all the time (not my field). A fuselage formed by winding carbon fiber tape around a male mold seems pretty straightforward, spars too. I don't know if a wing could be made with a precise enough profile in this way, interesting thought though. I know there are specialty companies applying all sorts of new composite technology. Farming out rather than investing in house might make a lot of sense in the small numbers world of sailplane manufacturing. Save on tooling, benefit from the sub's economy of scale. Certainly not business as usual in the glider industry. snip P.S. Sorry that this is so disjointed, dinner's ready :-) mines on hold.......had to take a dog to the vets...... Hope the pup's OK. Had to do this three weeks and four stitches to the leg ago. Shawn |
#7
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Bill Daniels wrote:
For example, how many buyers are there for a brand new LS-4 selling for $25,000 - quite a few I expect. Yes, you could sell one to me at that price, the trick is producing using traditional fabrication techniques for less than $25,000 in materials and labor. I don't think it can be done anymore... Marc |
#8
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Hi Guys,
I think that the tooling required to make the "simple" glider I propose need not be overly "sophisticated" After being intimately involved with the Russia kit and the Apis kit, and studying the TST- Atlas, I really belive that these ships and manufacturing methods are valid and produce nice aircraft. If all one looks at are the latest from Europe, or even the racing glass over the last 20 years, you get the impression that sophisticated tooling and elaborate parts are a must-have. Indeed, they probably are a must have for these ships, and these manufacturers have done a marvelous job with their tooling and thus the parts. But a simple glider does not need all those "parts" A fuselage plug can be made on a CNC router using REN board or any suitable tooling medium. My put would be to use a HD REN board, make a LH and RH plug split along BL-00, wax and PVA the heck out of it and pull a mold. The fuselage if designed right, would not require vacuum bagging, therefore several of the internal bits could be installed, taped in place and co-cured along with the skin lay-up, saving a lot of time and materials. A tool to wind a fuselage would require A LOT of money and most likely would not appeal to anyone with high ROI hopes. Wet lay-up is still a valid way to make a fuselage, I've layed up several in the last few years and it is actually kinda fun! As far as the wing goes, I think the LS-3 wing style is the way to go. Perhaps aerodynamicaly speaking it may suffer over a modern planform, but most of those modern planforms are on sailplanes that are state of the art and their prices reflect that. A simple tapered planform drives simplicity down the line: straight spar along the 40% C, straight rear spar, straight hinge axis, straight flaperon.................all these parts and their tooling/jigging would be far simpler and cheaper to manufacture. As Shawn shows in the link he posted, 3k carbon can now be found relatively cheap, compared to a year ago when availability was scarce and the price over $45 a yard. I would want to use the best material for the job; if it required carbon or e-glass then use it.................and of course a good epoxy. I am a shop forman doing composites; we are daily designing, cutting, and making tooling and parts and I know somthing like this can be done. As Jaun Trippe said, it is a Sporting game...............who wants to play? Cheers, Brad PS................Shawn, glad to hear your pup is OK.................ours is still at the vet.......... ![]() |
#9
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On Dec 25, 9:11*pm, Brad wrote:
I was browsing thru one of the Yahoo glider N.G.'s today and read where the World Class design may get ressurected. That got me to thinking: What would the ideal recreational next generation sailplane sailplane look like? I reckon it would be a Discus bT. Easy to fly, easy to rig, great performance, doesn't need a crew. As, well, everyone has says it's all down to production costs. Modern gliders cost a lot because the skills to build one are expensive - the cost is the labour, not the material. You can lower the labour costs by sourcing production from where it's cheaper, just as DG and Schempp- Hirth have done with contracts at factories in Eastern Europe with labour costs are less than in Germany. However composite production skills can't just be pulled out of thin air; I've seen first hand how good Chinese and Taiwanese metal workers are (exquisite mountain bike frames), but I'm not sure you could just rock up there and find a factory that could build Discuses. Even the Eastern Europeans screwed it up at least once with the DG300, which goes to show the challenges involved. I don't think automated production is a possibility for two reasons. The first is the market - with the way the market for new gliders is, and the way gliding itself is, you couldn't guarantee the production run needed for the set-up costs. The second is it's really not that simple to set up automatic production of composites - I've been following the 787 production story closely since well before things started going wrong. Boeing went all around the world for partners ans their major contractors - KHI, MHI, and Alenia - were the only people in the world who could mass-produce large composite components, and even then those companies have built factories with systems and processes (giant autoclaves, laser cutters, automatic lay-up machines, robot trolleys etc.) which simply didn't exist beforehand. (Which is why Airbus are so far behind Boeing on composite technology - when Boeing was contracting the Japanese for production, Airbus was contracting universities for basic R&D on composite mass-production techniques they could use in-house, knowing that Boeing had basically used up the world's supply of possible composite contractors.) Some of the smaller contractors have indeed messed up, partly leading to the now well-known production problems Boeing is having. Which is in no way bad news for the German manufacturers. Skilled hand- built products command incredible profit margins; as long as the company is well-managed (I've always wondered how RS managed to go bust after the biggest glass production run in gliding history) and has at least a sniff of a potential customer base it's possible to do very well in such a market. At the end of the day I have no problem with the market for new gliders being almost entirely very expensive hand-built products. I'm happy buying 30-year-old aircraft which still fly pretty well and are perfectly affordable. Not sure the US ever saw the influx of glass gliders the UK and Europe did though and if your used market looks like ours. Dan |
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At 21:49 26 December 2007, Brad wrote:
I think that the success of the Russia proved that there was and maybe still is a market for these lighter sports ships. I also sorta think that they saturated the market, and I also think that if the Russia had the 'look' that we sailplane pilots have come to expect, that they would still be in business. That is, if their price stayed somewhat the same. If the Apis was around at the same time as the Russia, I wonder how many Russia's would have been sold? Given that the price point was very close and the appearance of the Apis is so close to what we 'expect' I think the Silent may have been around, but don't think there was a US distributor at the time. Brad Any glider which has the 'look' that a bunch of old geezer sailplane pilots want is doomed to fail. Soaring has to evolve into a fun sport which is affordable to people in their early working years and what a bunch of old men want won't qualify. Soaring in America needs high altitude high capacity winch launch locations, two seat trainers which are economical to buy and operate and a single seat glider with launch and handling capabilities similar to the trainer so a student doesn't need to re-learn to fly so he/she can fly it. The K21 has already proven to be a great training aircraft and at US$64,000. might be economical to buy and operate. At over $100K it can't earn enough to pay for itself + instructor + insurance etc... That design could be brought to the US, made in larger volume, simplified, rougher surface, and no one learning to fly would care one iota about its performance. Ditto for a single seat glider which could handle a large number of winch launches and still have a return on investment. In a club or rental operation people would want to go flying, to hell with performance if it adds significantly to cost. And they won't care about class because they won't be flying in competitions. That's what old geezers with plenty of free time do. |
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