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#71
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Earlier, Eric Greenwell wrote:
Many people say they would be delighted to have a glider with the performance of an LS4. Yes, I'm trying to sell them on the HP-24 or its unflapped sister. Also, it's worth considering that the nicest thing about the LS-4 isn't necessarily its very decent performance, but rather its very, very sweet handling. The LS-4 is definitely the nicest-flying ship I've ever flown to date. I think that that low-workload handling is one of the things that helps bring out the best in pilots, and is the greater part of what has made the LS-4 so good and so popular. This performance can now be achieved with a smaller span glider of 13 M or less. I consider that an extremly debatable proposition. I'll wait to see a stub ship consistently beat an LS-4 in unhandicapped, nationals-level competition before I abandon my grain of salt. There seems to be something about having a little span that always makes you want a little more... Can you guess at the cost reduction that would be possible with a 12 or 13 meter glider compared to the 15M LS4? My guess is "relatively small" in an overall sense. Smaller factory, I think that facility size and overhead costs are more closely linked to product complexity and throughput than to span. The place where stubbies really shine is where people have to work on them in their own garages. I've had many people ask about glider kits that they can build in a 24-foot garage. less materials, Theoretically so. But in order to bring that 13m ship closer to your goal of 15m-type performance, you have to make it lighter per unit of area than a 15m ship. And that means more costly materials and processes. That's one of the reasons why Sparrowhawks go for $193 per pound versus about $100 per pound for a new-run LS-4. less labor (especially if hand finishing is needed) Yes, that's where there might be a direct area-balanced reduction (It's also one of the big reasons I'm developing a "some assembly required" glider). It's also the area where I think glider manufacturing would benefit most from capital investment in tooling and machinery that reduces the hand labor. smaller trailer, lower shipping costs (RO-RO is by volume, I think). All good points as well. But they also might suggest that there might be economic benefits to greater geographical diversity of manufacturing. In sum, I do think it would be great if there were more soaring pilots and soaring clubs that were satisfied with the performance they can get out of 13m or so. And I agree that, all things being equal, smaller gliders are less expensive than large gliders to manufacture, own, and operate. Unfortunately, all thing _aren't_ equal. I think that the unscalable aspects (specifically the pilot and their physiological requirements) will continue to drive a market that favor gliders greater than 13m for the general market. The one somewhat-troubling exception that occurs to me is full-on, no-holds-barred competition. I believe that where the stakes are high, there can be competitive advantage in a light, very small glider of 15m or slightly less. What we're talking about is a glider for a 5'2" pilot of about 108 lbs who doesn't mind launching at 11 lbs/ft^2 in a machine that provides about as much crash protection as a motorcycle racing suit. In the current market, where soaring competitors pay their own way, I don't see a huge demand for a ship like that, simply because of the self-selection of contest pilots, and their relatively strong interest in their own health and well-being. But in some possible future, we might encounter a market in which the driving economic force comes from outside the ranks of pilots, and in which competition pilots are specifically selected for their size as well as their skill, determination, and risk adversity (or lack thereof). I think I won't bet on it, but others might. Thanks, and best regards to all Bob K. http://www.hpaircraft.com/hp-24 |
#72
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Eric Greenwell wrote in message ...
Bob Kuykendall wrote: Many people say they would be delighted to have a glider with the performance of an LS4. This performance can now be achieved with a smaller span glider of 13 M or less. Can you guess at the cost reduction that would be possible with a 12 or 13 meter glider compared to the 15M LS4? Smaller factory, less materials, less labor (especially if hand finishing is needed), smaller trailer, lower shipping costs (RO-RO is by volume, I think). Eric, I wonder about this cost issue. Having done some re-profiling and re-finishing myself, I have to believe that the decrement in labor and materials involved in a 2 meter reduction in span is insignifiant. For instance, once you have the 600 grit on the sanding bar and you're moving right along, the last one meter of a given wing is lost in the overall effort of setup and cleanup. Although the materials are clearly incremental, the percentage of material is certainly less than 10 percent since the surface area of the last two meters is likely less than 10 percent of a modern wing (e.g. 115ft2 for a modern glass bird vs about 15 ft2 for the outboard 1 meter on each side [3 feet x 2 feet mean chord]). So, maybe we could optimistically see a 5-7% reduction in per unit construction cost. Throw in tooling and development costs, and what's the real savings? That's at least how I would view the numbers if I were setting up shop... I think 13M is a legacy of the "build it in your garage" movement. In that case, there was a very practical reason for a 13M span; the half-span would fit in an average garage (aka "workshop"). But, since the homebuilders movement is pretty much moribund except for a few hearty soles, what's the magic about 13M? Erik |
#73
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wrote in message ... A hip replacement isn't sitting in one position for two years at a time. Oh, I don't know. You should see some of the layabouts in my houshold! :-) Ian |
#74
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Lighter wings?
Cain't lif' that heavy glass no more. Cheers? "Erik mann" wrote in message om... Eric Greenwell wrote in message ... Bob Kuykendall wrote: Many people say they would be delighted to have a glider with the performance of an LS4. This performance can now be achieved with a smaller span glider of 13 M or less. Can you guess at the cost reduction that would be possible with a 12 or 13 meter glider compared to the 15M LS4? Smaller factory, less materials, less labor (especially if hand finishing is needed), smaller trailer, lower shipping costs (RO-RO is by volume, I think). Eric, I wonder about this cost issue. Having done some re-profiling and re-finishing myself, I have to believe that the decrement in labor and materials involved in a 2 meter reduction in span is insignifiant. For instance, once you have the 600 grit on the sanding bar and you're moving right along, the last one meter of a given wing is lost in the overall effort of setup and cleanup. Although the materials are clearly incremental, the percentage of material is certainly less than 10 percent since the surface area of the last two meters is likely less than 10 percent of a modern wing (e.g. 115ft2 for a modern glass bird vs about 15 ft2 for the outboard 1 meter on each side [3 feet x 2 feet mean chord]). So, maybe we could optimistically see a 5-7% reduction in per unit construction cost. Throw in tooling and development costs, and what's the real savings? That's at least how I would view the numbers if I were setting up shop... I think 13M is a legacy of the "build it in your garage" movement. In that case, there was a very practical reason for a 13M span; the half-span would fit in an average garage (aka "workshop"). But, since the homebuilders movement is pretty much moribund except for a few hearty soles, what's the magic about 13M? Erik |
#75
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"Jacek Kobiesa" wrote in message om... "Janusz Kesik" wrote in message ... U¿ytkownik "Mike Hessington" napisa³ w wiadomo¶ci ... Also, most the european manufacturers will see a big impact, affecting their production, because individuals in the U.S.A. were buying more new gliders then any other countries. So, the European manufacturers can adjust their prices for the U.S. market or...massive layoffs? to many built gliders and no buyers? Well, time will show... Thats not the impression I am getting. The drop off in new glider purchases from America started 3 years ago. The dollar is only the latest thing to affect that. The order books for the factory I represent have filled out alot in the last year to my surprise and waiting times have increased markedly. |
#76
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Fred Mueller wrote:
A 40:1 13 meter glider? Remember when we thought 15 meters would never exceed 40:1? Now they exceed 45:1, so 40:1 in a 13 M glider designed today is quite practical. Tell me about the wingloading. What would you like - more or less than the LS4? Either or both is practical. -- Change "netto" to "net" to email me directly Eric Greenwell Washington State USA |
#77
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Bob Kuykendall wrote:
This performance can now be achieved with a smaller span glider of 13 M or less. I consider that an extremly debatable proposition. I'll wait to see a stub ship consistently beat an LS-4 in unhandicapped, nationals-level competition before I abandon my grain of salt. There seems to be something about having a little span that always makes you want a little more... I think this is one big barrier to lower cost gliders, all right: incremental additions seem like a good value, and after a few of them, the complaints start coming about how much the glider costs! You know how it goes: retractable gear doesn't add that much in cost; water ballast is only a few layers of glass to stiffen the wings; winglets are pretty cheap; another meter or two of span hardly adds to the price; and so on. At the end of these "it doesn't cost much to ..." additions, we have a significantly more expensive glider. It's the same way we turn an $18,000 car into a $25,000 car, then complain about how much cars cost. snip less materials, Theoretically so. But in order to bring that 13m ship closer to your goal of 15m-type performance, you have to make it lighter per unit of area than a 15m ship. And that means more costly materials and processes. That's one of the reasons why Sparrowhawks go for $193 per pound versus about $100 per pound for a new-run LS-4. But, at 150 pounds versus 500 pounds, the SparrowHawk would still be cheaper! I don't know what the economic comparison of pre-preg carbon versus wet lay-up fiberglass construction is, but it would be an interesting one to read. The pre-preg is more $ per pound, I'm sure, but you need less pounds of it for the same strength, and laying up the pre-preg is easier than wet lay-up. In any case, a 13 meter ship would not necessarily need to be pre-preg. THe SparrowHawk uses it to meet it's 150 pound weight goal. -- Change "netto" to "net" to email me directly Eric Greenwell Washington State USA |
#78
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Erik mann wrote:
I wonder about this cost issue. Having done some re-profiling and re-finishing myself, I have to believe that the decrement in labor and materials involved in a 2 meter reduction in span is insignifiant. For instance, once you have the 600 grit on the sanding bar and you're moving right along, the last one meter of a given wing is lost in the overall effort of setup and cleanup. Although the materials are clearly incremental, the percentage of material is certainly less than 10 percent since the surface area of the last two meters is likely less than 10 percent of a modern wing (e.g. 115ft2 for a modern glass bird vs about 15 ft2 for the outboard 1 meter on each side [3 feet x 2 feet mean chord]). So, maybe we could optimistically see a 5-7% reduction in per unit construction cost. Throw in tooling and development costs, and what's the real savings? That's at least how I would view the numbers if I were setting up shop... Compare the 113 sq ft, 15 M, 513 pound LS4 with the 82 sq ft, 12.6 M, 290 pound AC4 Russia: that's a 27% reduction in wing area and a 43% reduction in weight! The fuselage is smaller, too, but not as much a reduction as the wing. That seems to me a significant reduction in finishing is possible, and also in the construction. Of course, an obvious difference in materials cost (these are both fiberglass gliders). But, since the homebuilders movement is pretty much moribund except for a few hearty soles, what's the magic about 13M? Nothing magic about the 13 meters, except it's big enough that I think a modern design can match the LS4 in performance (it IS a 24 year old design, after all!), which has become the de facto "minimum acceptable performance" for the more vocal on the newsgroup. We know it no longer requires 15 meters to match LS4 performance. 13 meters seems likely to achieve that, and the overall size is enough smaller to make real cost reduction possible. -- Change "netto" to "net" to email me directly Eric Greenwell Washington State USA |
#79
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Hi,
Does anyone have the name of the person or company that is planning to produce the LS-4s? Thanks, Paul Remde "Mike Hessington" wrote in message ... You can't fly your friends in a PW6. They will be to busy laughing at you. At 01:06 07 November 2004, Charles Yeates wrote: Good news -- but you could buy a PW-6U two-seater for 41,200 Euro and have the pleasure of flying friends, eh? Talking about the LS-4b: It's back in production (by Walter Eisele, a well-known german glider pilot), now called LS-4/2005. Price is 39.400 Euro, complete with retractable gear and water bags. Winglets are optional. Lots of bang for the buck if you ask me. Bye Andreas |
#80
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On Wed, 10 Nov 2004 23:06:18 GMT, "Paul Remde" wrote:
Hi, Does anyone have the name of the person or company that is planning to produce the LS-4s? Walter Eisele. Bye Andreas |
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