Issues and Solutions for kit- and plans-based sailplanes and motorgliders

Discussion in 'Soaring' started by TerryM76, Sep 3, 2019.

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  1. Sep 4, 2019 #61

    Topaz

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    M, I heard person after person at the workshop express an interest in a modestly-performing, self-launching sailplane or motorglider. Every single one of them who said it out loud got a "yes, but performance," or "Sure, that's ... nice" response from the speakers or the panel, except Neil, whose presentation was arguing the same thing - we don't have to have top performance in Every. Single. Glider., and there are other factors that are important, too, and that sometimes, for some missions, those factors outweigh absolute aerodynamic performance. The single aircraft type mentioned in the presentations on either day, that got the most actual interest in terms of enthusiasm from the audience, was when Neil was talking about restoring the three AS-K14's going/gone through his shop. What does that say?

    I came away from this event energized and wound-up for my own effort, as always, but also down-hearted and ever-more-convinced that, like PiperCrusin's impression, if we continue on with current attitudes, the sport's future is "hopeless" in the US. I'm still going to continue soaring, but at this rate it'll end up with me on my own in a self-launcher, because the clubs and FBOs will be gone if we continue the way we're going now and, even if they aren't, I'm getting tired of dealing with the elitist attitudes.
     
    Last edited: Sep 4, 2019
  2. Sep 4, 2019 #62

    proppastie

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    lots of words....I for one do not like to work with carbon or glass. cough cough, scratch scratch, pass the chemo. Van has proven the path to kit heaven is a CAD/NC punched or drilled aluminum box of parts.
     
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  3. Sep 4, 2019 #63

    mm4440

    mm4440

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    When I asked Van he said there was not enough potential sales to justify the engineering and tooling up costs for a modern two place medium performance sailplane. A motorglider? I wonder what the Xenos sales are?
     
  4. Sep 4, 2019 #64

    PiperCruisin

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    I would not discount molds right away. Depends on the mission. I'm guessing that they type you are thinking about, molds are probably going to be minimal if at all.

    I think we all envision different missions and we probably need to define a few and what the general candidate might look like and start a thread for each one.
     
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  5. Sep 4, 2019 #65

    Topaz

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    Probably pretty low. But I guarantee that Sonex isn't selling them at a loss.
     
  6. Sep 4, 2019 #66

    PiperCruisin

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    Don't know but FAA says 25 registered/built. If it had a bit better glide ratio (closer to 30) and a way to get it into a standard t-hanger would it sell better? Hard to know until that is available to buy. Alas it is not. I have some faith that if you build it they will come. I'm guessing Van's won't do it. Would he help get someone started that would take up the torch?

    The benefit of aluminum is you don't need as much tooling (mostly for ribs) since it is mainly CNC punch (not sure how RVs are done). Maybe Bede/Grumman bonded aluminum skins is something to consider for better surfaces.
     
  7. Sep 4, 2019 #67

    Topaz

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    The other benefit is that it can operate from dirt strips with near impunity. At Skylark (Elsinore), the main club there won't buy composite ships, even if they can get a great deal on them. The dirt blast from the tow-plane chews up the surface finish in no time, unless you put an extension on the tow rope. You end up paying out a lot in maintenance of the gelcoat than you would for an aluminum glider, that just needs paint. It wasn't felt that tow-rope extensions were safe for student training or low-time pilots going solo, so the only composite ships that flew there were privately owned, and the decision to use an extension on the rope was left to the pilot himself. This would be true of any airport that doesn't have a very clean paved runway.
     
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  8. Sep 4, 2019 #68

    Pops

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    My sister's grandson is 30 years old, and got his glider license earlier in the summer. Lives in Oregon.
    Add one more.
     
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  9. Sep 5, 2019 #69

    BoKu

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    I propose we have a discussion about this scourge of elitism that appears to be wracking our sport.

    Because I think I know something about it. I campaigned a creaky old HP-11 in and around Minden for a dozen years, camping next to the glider in a rusty old van. I operated among the very best and richest in our sport using my patched-together tin glider and a trailer that a friend welded together in his backyard.

    And, yes, there were some snobbish-to-the-core snobs to whom you'd apply the e-word without a moment of hesitation. Who honestly believed that they deserved to pull ahead of me in the launch line because they had 22 meters of span and a record to break. Who would not lift a finger to help me off the runway.

    But by and large, those were a tiny minority, and reviled even by their economic peers.

    The vast majority were entirely, completely supportive of my low-dollar approach. Were free with their advice and assistance. Would retrieve me as I occasionally retrieved them. Mentored me and other newbies who came up from where we'd done our training. Applauded our prudence and occasional touches of boldness.

    So, please clarify so we can better understand the problem from your perspective. How is this elitism expressed, how does it hurt our sport, and how do we mitigate it?

    Is the idea that cross-country soaring is more exciting and engaging than local soaring elitist? Serious question. Because I think that by any objective measure, cross-country soaring is more fun. You see more scenery, you do more thinking and strategizing, you are more engaged.

    I don't think that there is any argument that someone who thinks that they are a better person because they have a 50:1 glider instead of a 40:1 glider is indeed elitist. And as noted above, they do exist. But as also noted, they are a tiny tiny minority.

    Likewise, the idea that a 50:1 glider is inherently better than a 40:1 glider is inherently elitist. Better for what? And why?

    But I reject the idea that my love of cross-country soaring is elitist, that it somehow damages other sectors of our sport. I likewise reject the idea that it's elitist to understand that a 40:1 glider is more useful for the kind of soaring I want to do than a 30:1 glider.

    I also reject the idea that it is elitist to believe that new low-performance gliders won't do much for our sport, even if that belief is for whatever reason misguided.

    --Bob K.
     
  10. Sep 5, 2019 #70

    Hot Wings

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    I don't think he is side stepping the other CODB $'s....If it's apples to apples. Once the mold and support equipment is in place producing from a mold is so much quicker that that cost should be amortized rather quickly compared to the cost of the simple tooling needed for a stick built or tube and gusset aluminum structure - AND - the labor to make those many simple pieces.
    There never will be a quick build wood AV-36 kit. There is just too much labor involved. There may be prefab curved laminated parts because of the time needed to make those forms. Even then I'd prefer to find a way around having to use the laminated parts.
    If I ever get to the ASTM LSA version it will be predominantly a composite kit......Aim high with the goals. ;)

    Added:
    My version of the Woodstock wing would look something like a classic Marske carbon rod spar with either a glass or ply "D" skin with carbon capped foam ribs aft and latex painted Dacron cover. 100% build-able in the average garage but the major structural parts can be economically supplied in kit form.
    But this is going down the construction path rater than the path the OP pointed to.
     
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  11. Sep 5, 2019 #71

    Hot Wings

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    in this case elitist is not the right work.
    But claiming that a 40/1 is more useful than a 30/1 is kind of pandering to the lowest common denominator by enabling those of less skill to to achieve what a better pilot with less sophisticated equipment could. There is nothing wrong with lowering the bar for if it allows more people to participate.
    It is elitist to go the step further and insist that the lowering of the bar need to be done only with a pure powerless glider, of higher performance.

    I saw the same thing back when I was bicycle racing. If you didn't have top of the line Campanella equipment and expensive sew-ups on an Italian frame you got looked down on.....until you finished in the top places with a Schwinn frame and clincher tires. Then you got DQd because you had 8 inches too much top gear. o_O
     
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  12. Sep 5, 2019 #72

    Topaz

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    How magnanimous of you. I've only been trying to have that discussion for the last three pages...

    Is that the "royal 'we'," Bob, or are you rhetorically isolating me again? How about you read back the last three pages, rather than suddenly pretending to show interest in it and expecting me to write it all out again? Because I don't think you're really interested in having any kind of actual discussion when you spend this and the rest of your post, like all the others in this thread, saying there really isn't a problem, ignoring it, minimizing it, and dismissing the chance that there even might actually be a problem at all.

    In a vacuum, no, it's not, and I'm genuinely glad you enjoy that kind of flying so very much. If that's what you think, fine. But don't go telling other people what they should think. Don't tell other people that your way is the only way. Which is what you've been doing in this thread.

    So, despite your so fervent desire to now have a discussion, "it's not really a problem." That's... not a discussion.

    Then pray tell me why the idea that a 40:1 glider is inherently better than a 30:1 or even 20:1 glider is not elitist? You've been making that assertion baldly throughout this thread. If cross-country is your cup of tea, hey, more power to you. I've been saying repeatedly that I don't think carbon fiber, high-performance ships, or cross-country competition are bad. But those aren't the only worthwhile and viable kind of soaring, unless you want to take the elitist position that they are. And non-cross-country soaring, local ridge or thermal soaring, micro-lift soaring, etc. do not require and are not "better" in a 40:1 ship. They're not. It's way more capability than you need.

    Your personal love of cross-country soaring isn't elitist. I'm sure a 40:1 glider is most certainly more useful for the kind of soaring you want to do (emphasis mine) than a 30:1 glider.

    You can believe it, but you've yet to demonstrate that it's actually true, and you keep rejecting it in the face of a whole lot of people, here and elsewhere, that feel and express themselves otherwise. I've said that repeatedly but, even though you claim that you're "now" interested in having a discussion about it, you're still rejecting the very idea out of hand. That's not a discussion, Bob, and you're showing that, no, you really have no interest in having one.

    It's not elitist to like what you like and want what you want, no matter what that might be. It is elitist to suggest that your way is the absolute only way that's interesting, viable, or worthwhile, and that others who seem things differently are simply ill-informed and misguided. It's elitist to discourage others who want to try something different, just because it's not what you happen to like. Elitism is minimizing, diminishing, or hand-waving away what they want, just because it's not what you want. I've seen that kind of response, first-hand, to questions about lower-performance gliders and motorgliders: last weekend a the ESA workshop, last year at the ESA workshop, the same place in 2016, and every single soaring gathering I've attended, from a lot of people who prefer cross-country. I've seen it on the web, in the SSA and ESA, and here in this thread, from you.

    You're not interested in a discussion. You're just here to tell us that cross-country soaring in high-performance sailplanes is the only viable and worthwhile part of the sport, the only one that generates participants that "we" want to "attract, foster, and retain," and that we're all misguided or ill-informed if we think otherwise. Which is exactly and precisely the problem I'm talking about, even if you choose not to see it. This entire thread is such a shining and disgusting example of the problem that I'm amazed I'm putting this much energy into it and burning this many bridges for it.

    Whatever. Think what you want. I'm out.
     
    Last edited: Sep 5, 2019
  13. Sep 5, 2019 #73

    TFF

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    Here is a surfer analogy. There are only so many waves, so you want to maximize catching one and are protective of those chances. A high performance glider fits that need and I can see the pilot being protective of his shot that day. Here is the counter. We are looking to surf a wave machine in a water park in Peoria, Illinois. We want waves anytime we have time. Not anywhere near the ocean but we want to pretend for a minute. One way is a sport, one way is a pass time. Highest regard for the sport, but many don’t have the time. Same with aerobatic airplanes. Do you want to pull some Gs in a Pitts S1-C at lunch break or are you practicing Advanced Schedule with a Giles? Totally different yet in the same place.
     
  14. Sep 5, 2019 #74

    Victor Bravo

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    Another perspective, perhaps:

    I was once one of those 40-1 composite snobs, silver spoon in my a** and everything, competing at the national level. I also had learned to fly in the 2-33 and flown the 1-26, like most people in soaring. Had a great time in the 1-26, the Blanik, the Pilatus, and the (rare) IS-29 Lark 1. Got into glass sailplanes and never looked back. Was on my way to fame and glory, ready to knock Ingo and Bruno and all of them off their podiums. Then, as they say, life happened and I was no longer able to continue my quest to break records and race in the nationals. Don't cry for me, Argentina, I had it coming I guess. Stupidity has its price.

    Fast forward 30 or so years.

    Right at this moment I'd be **** lucky to have a 1-26 to fly, and I would be very happy to have one to fly, just to thermal around and scrape the bottoms of the clouds off. There is probably no way in hell that I will be able to resume my career as a snot-nosed elitist yacht club mentality sailplane racer. But flying up in the mountains and chasing cloudstreets still calls me.

    The point of this corpulent rant is that I've enjoyed and loved both "ends" of the soaring spectrum, and there is an equal place for both. I think the best way to put it is that it's two separate hobbies. (It may be important to note that the world's best and most successful sailplane pilot, who at this very moment may be soaring above 76,000 feet in the Perlan, spent many happy years as a competitor in the 1-26 class.)

    So the point is that there should not be such a huge battle of ideologies with respect to a sailplane kit made out of any given material. I truly think that BobK's HP program is an absolute winner, and so is the Sandlin GOAT program. And so would be the 1-26 kit if the Schweizer family put it back into production.

    It is also fair to say that a glider kit (or factory glider) in 2019 has to be different than it was in 1985. Nobody wants to put together a million sticks to build 36 completely different ribs in each wing. Nobody has that patience or time any more. So what... we can build stuff differently. We can cut out those 36 ribs in each wing using Fritz' CNC router in a day. We know how to cut the ribs out of foam and carbon strips. The built-up Kolb ultralight wing ribs are built from cheap aluminum tube and pop rivets in 9 minutes each (factory).

    The infrastructure for soaring is also different now, and needs to be addressed. So... address it. Electric self-launch works well with existing shelf hardware now. The home-built car mounted wheel drum winch works well enough for light weight gliders. Car tows cost less than a dollar's worth of fuel for a light glider. Yes of course there are obstacles, but the obstacles balance each other. If you could save 60% of the cost per hour of flight time compared to a powered single seat LSA maybe it's worth dealing with. Maybe not for some folks, but that's the same for any type of flying.
     
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  15. Sep 5, 2019 #75

    Victor Bravo

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    Because I studied the Kolb ultralight, this popped up in my head: The last and highest performance of the Backstrom Plank series "Super Plank", was reportedly calculated out at 30-1. Not bad at all for a Hershey bar wing with no special airfoil and no molds. And it had a short span for a glider.

    The Kolb wing is built on a tube spar with really simple and light built-up ribs. The ribs slide onto the tube and are pop riveted on. The powered Kolb doesn't have leading edge sheeting, but a plain sheet of .016 aluminum could easily enough be put on... it would be totally non-structural.

    The tube spar wing and simplified ribs would take a fraction of the time to build compared to wood sticks or even laminated wood spars and a torsion D-tube.

    A simple Graham Lee / Baslee fuselage pod, tube and gusset, would also go together very very quickly.

    The Plank, despite several shortcomings, is shown to be reasonably safe and predictable when kept within XYZ center of gravity limits.

    Importantly, as a flying wing type of aircraft, the bending loads on the spars are a bit lower, getting better and better as the fraction of "non-lifting components" gets lower. Also, battery weight can be more easily spread out along the span to minimize the effect on bending loads. A 20HP electric motor (puher, at the trailing edge) is likely enough for this use.

    If designed to accomplish this, the battery weight and motor weight can cancel each other out as far as balance, so the same aircraft could be built as either a powered or unpowered glider.

    So a longer span version of this aircraft, using the above construction techniques, IMHO has some potential for an "everyman's soaring glider" that addresses more of thebarriers and issues than some other ideas.

    Backstrom_EPB-1_Super-Plank[1].jpg
     
    Last edited: Sep 5, 2019
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  16. Sep 5, 2019 #76

    proppastie

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    Not having the experience enough I do have a question, will a 30:1 microlift glider be good for cross country soaring?
     
  17. Sep 5, 2019 #77

    mm4440

    mm4440

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    I believe Garry Osaba won a contest day in the Carbon Dragon when the racing gliders could not stay up on the micro lift he could.
    The answer is yes, especially down wind. Micro lift gliders are usually more min minimum sink oriented than max L/D. In the booming desert west there could be days too strong to fly a microlift glider. Goats have done cross countries.
     
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  18. Sep 5, 2019 #78

    mm4440

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    Hi VB, I'll post a sketch later.
     
  19. Sep 5, 2019 #79

    mm4440

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  20. Sep 5, 2019 #80

    rdj

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    As both an SSA and ESA member I've been following this thread with interest because I completely understand where both Topaz and BoKu are coming from. I think TFF nailed the crux of the argument here: what is the sport of Soaring?

    My goal as a soaring pilot is to acquire a sailplane capable of cross-country flight and pursue badges. However, the nearest soaring fields with available tow planes are an hour and a half away from me in either direction. (One of the primary uses I have for the LSA I'm building is to get to those fields so I can actually enjoy the sport.) Flying from those fields support the 'sport' of soaring and keep the operators in business. To do that, and to achieve my soaring goals, I really need an HP-24, 1-26, or some other 'true' sailplane. (Working on it.)

    OTOH, I've also been sketching plans for an easy to build, easy to fly self-launching plane with one simple mission: allow me to head to the local airport only 10 minutes away and launch quickly after work for an hour or so of just drifting around enjoying the fall colors, turning those nasty summer bumps into micro-thermals, or watching the sun set on the Sierras. Something like what Topaz envisions, I believe? In my mind a low min sink is more important than max L/D, and an electric motor and slow-turning feathering prop much quieter than a 10000 RPM 2-stroke. 'Glide ratio' is mostly about needing less energy to climb, an ability to maintain altitude, and being able to return safely to the airport sans motor. However, is this really 'soaring'? From the perspective of 'the sport', it really does nothing to support the sailplane fields or their operators.

    The discussion on material selection and fabrication techniques is interesting (I argue with myself all the time about the same topics) but isn't it putting the cart before the horse in this case? Have you two even agreed on the definition of the sport yet?
     
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