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Old Oct 19, 2009, 09:03 PM
G_T
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For those who are watching this thread in Dutch:

The 100g weight limit is the design weight for the entire plane. There is a similar plane design of mine, the Zone 2P. The design for the 1M wing is intended to use tails of the design of the Zone 2P, except that they are to have reduced span.

http://www.rcgroups.com/forums/showthread.php?t=1106218

The airfoils used in this 1M wing are defined in the discussion thread:

http://www.rcgroups.com/forums/showp...4&postcount=19

Also linked there are the tail airfoils, and the Spring-V full flying horizontal tail mount.

Gerald
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Old Oct 28, 2009, 11:43 AM
G_T
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I have received requests for a lower aspect ratio 1M wing design, both to ease the weight limit a little and to make servo installation a touch easier. The wing published here is AR=9. I have an AR=8 wing design that is nearing completion. When I'm done with it the performance should be basically the same and the target weight will be 115g for the plane. A little lighter than that is better though. I should be able to get this design out by the end of the weekend.

Gerald
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Old Oct 30, 2009, 09:19 PM
G_T
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Hello everyone,

I have a new wing here for you. This replaces the previous wing. It's performance is better in all respects, by enough to notice. The biggest boost is in ground coverage.

Target weight is 115g for the plane. Aspect Ratio has been reduced to 8. This should make servo installation a bit easier, and the target weight should be a little easier to hit.

Gerald Taylor
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Old Oct 30, 2009, 10:33 PM
Walter Roos
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Thanks Gerald,
I'll get David Forbes working on it right away.

walt

Looks like I'm going to have to learn to roll my own.
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Old Oct 31, 2009, 01:48 AM
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Thanks Gerald! Very cool that you have take time to do this.

I will put some pictures here, during the build of the mini Zone.
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Old Nov 03, 2009, 10:31 PM
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...but...but I've just finished building something else...bah! damn you :P

Well it's raining anyway...
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Old Nov 05, 2009, 11:06 AM
G_T
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Well, I've said it before but perhaps it hasn't been noticed... I consider all of my work to be work in progress. Anything I release usually doesn't stay my latest and greatest for very long. Must stuff just stays in the computer though unless it is significantly better or otherwise generally interesting.

Several people/groups are working to push the state of the art, around the world. Some publish details and some only publish generalities (or nothing). The state of the art is far from stationary in DLG right now. That is exactly what you'd expect with a first WC coming up in a little under two years, and DLG itself being relatively few years old. The 2009 season is over and individuals and teams are going full speed ahead on designs for 2010. I expect more interesting things to get released in the next few months.

So Pook, if you build this wing, just consider it an opportunity to have more planes available for next year

Gerald
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Old Nov 05, 2009, 01:01 PM
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Congress, AZ
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Gerald,

The latest wing is interesting. What if that planform was enlarged to 1500mm? What kind of results would you expect?

Gary
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Old Nov 05, 2009, 01:48 PM
G_T
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Gary,

In a nutshell a VERY fast wing with very high L/D but speeds in general would be too fast for small or light thermals unless made light and there might be significant flutter issues. The issue is using the Zone-40 at the root of a bigger plane. Changing that airfoil would necessitate changes in planform. For that matter, even just enlarging the wing would necessitate some changes since the Re effects do not scale linearly.So one would be back to square one with designing a new wing.

If people are interested in a lower aspect ratio version of the Zone 2P wing I can create one. I'm certainly set up to do it. Actually from analysis I've run since the 2P wing was designed, the performance would be higher across the board. Someone let me know if they want it. It does require a full plane update not just the wing planform. The tails would need minor adjustments. I'd change the wing's AR down to 10. Down to 9 would boost the performance even more, but that is a wing-only analysis. The tails would have to be getting notably bigger. And the throwing weight would be higher. Not sure how that would play out for most. AR=10 is safe though. It wouldn't be just a straight enlargement of the wing chords. The tip wouldn't get as much increase as the root.

However I have other projects in the works.

I have a new wing series nearing completion but it is totally untested. I don't like releasing foils until they are tested and right now I'm not sure who is going to do the tests. It is at the stage of "meets requirements" and I'm making micro tweaks to boost the performance a little higher, or trying to at any rate. When it gets very difficult I am done. It is getting there. I'm pretty sure the series will be fine which is why I'm willing to talk about it now. I have been keeping it quiet. Anyway it is not a replacement for the Zone, at least not yet; it is something different. The series has most of the speed performance of the Zone series but much greater tolerance for being flown too slowly. It is still a fast series by most standards just not when compared to the Zone. It would be the second fastest published series. I'm not going to predict when it will be released so nobody should wait for it. It has been in progress since I released the Zone foils. It took me a while to figure out how to do what I want. I've got a few hundred hours into this one.

It is also possible at some point I may re-release the Zone series to correct an idiosyncracy in the series that doesn't hurt performance but makes it a real pain in the @$$ to design a molded wing. The update wouldn't be needed for those making 2 or 3 panel wings. The current series is quite fine for that. It is just that if one looks at the Zone-36 and the Zone-40 they are both good foils. They are just a bit more different from each other than they should be for adjacent foils in the series. That pair at least stands out in my mind, but it shows the pattern. I was a bit aggressive in optimizing the individual foils after generating the parent series or else I did something strange in the original generation that I've forgotten, but anyway I didn't keep them as close to a linear series as I thought I had done and as I've stated I did. No concrete plans to "fix" that yet though. I have spent a little time looking at it and fixing it is not trivial. Some foils such as the Zone-36 are too good. It is very much easier to make the foils worse than to match or improve their performance when reformulating the blends.

Gerald
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Old Nov 05, 2009, 03:32 PM
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Quote:
Originally Posted by G_T View Post
Gary,

I Changing that airfoil would necessitate changes in planform. For that matter, even just enlarging the wing would necessitate some changes since the Re effects do not scale linearly.So one would be back to square one with designing a new wing.

Gerald
Damn I was afraid of that. Both muto and I fly FAI S8Ep which has a minimum wing span of 1.1 meter, max AUW 300gm. We both like 1.2-1.3M to lower the wing loading. These are very close to DLGs in all other aspects except we don't throw them into the air, they go up on rocket motors. [6 newton/sec. average impulse, approx 1.3 pounds thrust for 7 seconds] I was thinking to scale up the 1M wing or scale down the 2P so my question is; [knowing you have a full plate already] would one of the preceding be preferable to say leaving the root cord the same and only increasing the aspect ratio to the desired span?

Ok so who let the weirdos in :P

Richard
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Old Nov 05, 2009, 03:49 PM
G_T
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In the 1.2-1.3M range, I would expect the Zone-46 to be appropriate for the root, and then the panel break would likely be Zone-36. Anyway that combination should perform pretty well. But I wonder about the lowering of the wing loading because you are upping the total mass. You will have less starting altitude and the sink rate won't be all that much better. Myself, I would be tempted to scale the 1M wing out to 1.1M, just by extending the panels but leave the tip curve alone. That small a change won't make a big difference. And then build it as absolutely light as possible.

Unless I am mistaken, you have a working window for launches? If so then you should be able to choose when to launch and to a limited extent in what direction. With good air reading skills, one shouldn't have to cruise very far to get to lift. So I would think min sink performance would be more important than max L/D. I would also think launch height would be more important than max L/D. That's why I think the smaller, lighter plane is the best bet.

Since I'm guessing the launch loads are front-to-back on the wing but are otherwise fairly light, I'd use a biased skin of probably 1oz Kevlar in a dry layup over perhaps 40PSI cores, and no spars. Just don't do any aerobatics with it! That should give you a super light wing. It won't be as durable as a wing with spars but I think it would be a superior competition machine. You may even be able to get away with 25PSI cores in the outer panels and that would be an improvement. It would reduce launch stresses on the wing among other things.

Gerald
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Old Nov 06, 2009, 12:09 AM
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Gerald,

I appreciate that your doing lots of stuff. If you want to do the 1.5 meter wing in a lower aspect ration, I'll build it and give feedback.

Gary
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Old Nov 06, 2009, 12:41 AM View Post
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Old Nov 06, 2009, 08:23 AM
Walter Roos
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Canton, Ga.
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Gerald,
I'm not yet a bagger, but I have destroyed my share of wings, so why no wing spars, I know every gram counts, but it seems to me that at least some kind of spar is necessary during launch. If no spar, then you had better not turn that sucker (blower for the west coast) up too quick on launch.

Or are you talking about Richard's rocket launch ??
walt
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Old Nov 06, 2009, 11:07 AM
G_T
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I was talking strictly for FAI S8Ep, from my extremely limited knowledge of it.

Gerald
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