We flew today....

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snoopy
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We flew today....

Post by snoopy »

For my aerodesign project- I wasn't there and havn't heard how it went yet.... cross your fingers for me, folks.
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roid
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Post by roid »

goodlick
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Post by Sage »

what roid said :wink:
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Post by Dedman »

Good luck snoopy. Remember, you don't get any style points in this competition. Get the cargo up, get it around, and get it down in one piece.
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Post by MD-2389 »

Good luck! :)
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Nitrofox125
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Post by Nitrofox125 »

Pics! Results!

But good luck!
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snoopy
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Post by snoopy »

Pics, video might be coming.... it flew really well, though- no payload yet... Second iteration will be started within a few days.
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snoopy
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Post by snoopy »

Flew again today....

lifted 8 lbs no problem (that's qualifying weight)

Crashed once, rebuilt all day, and got back out there for some successful flights right before sun-down.

[EDIT] flow stays laminar over the whole chord, too. That's really impressive considering our wing. 32" root chord, selig 1223 airfoil (massive chamber)
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Post by Dedman »

snoopy wrote:flow stays laminar over the whole chord, too. That's really impressive considering our wing. 32" root chord, selig 1223 airfoil (massive chamber)
Sweet!! Is the center of the weight box at or near the aircraft CG? It should be.
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snoopy
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Post by snoopy »

yep.
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Instig8
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Post by Instig8 »

Where are all the juicy details and pictures?
snoopy wrote:Flew again today....

lifted 8 lbs no problem (that's qualifying weight)

Crashed once, rebuilt all day, and got back out there for some successful flights right before sun-down.
What happened? Pilot error? Equipment failure?
snoopy wrote:[EDIT] flow stays laminar over the whole chord, too. That's really impressive considering our wing. 32" root chord, selig 1223 airfoil (massive chamber)
Too much laminar is bad, right? Any washout or dihedral built into the wing?

Just wondering.
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snoopy
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Post by snoopy »

Pictures arn't going to happen, I think. I don't have any way to host them, and don't have direct access to them. As far as the crash, we where trying to do a low speed-low altitude pass in order to get a look at the tufts on the top of the wing and we slowed down too much, unexpectidly stalled about 3 ft off the ground, and hit hard. Due to bad design, the hard hit caused the power to switch off. When the power switched off, the engine was at full throttle. The initial hit didn't do too much damage- the landing gear was designed well enough (by yours truely), but the switching off was bad. That meant that we had a plane running at full throttle with no way to steer or back off on the throttle. The plane then continued to plant itself in the ground.

Laminar is good- that means that the air flow doesn't separate, therefore the wing creates a low pressure above itself for the full length of the chord. There's a 2 deg dihedral built into the wing.

BTW the opposite of laminar is turbulent- you may have heard of that term.... turbulent is bad.

We flew again today... with a gross weight of 22lb and we still can still do better....
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Post by woodchip »

Snoopy, one word = success....dirigible
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Post by Top Gun »

Snoopy, if you can get access to the pics and just need some short-term hosting, and if it isn't an inordinately huge amount of pics, I can host them for you.
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Post by MD-2389 »

Or e-mail them to me:

md2389@gmail.com

I'll post them for you.
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Post by Darkside Heartless »

MD-2389
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Post by MD-2389 »

Pic 1
Pic 2

~850kB each
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Post by Lothar »

Wow... very strange design.

Who's the girl?
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woodchip
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Post by woodchip »

Reminds me of a zygoptera
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snoopy
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Post by snoopy »

Lothar wrote:Wow... very strange design.

Who's the girl?
The girl is another member of the team.

The tail is extremely high like that because of the need to be able to rotate to maximum angle of attack on the ground. Basically, at max weight you're on the virge of stall from the moment you leave the ground.

Thanks for the hosting MD.
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Post by Dedman »

It looks way too aerodynamically clean. I think you have wasted planform area that you could have put into the wing. Cool looking bird though.

Good luck Snoopy.
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Post by suicide eddie »

similar wing to a Ekranoplan, how stable is the handling with such a broad wingtip and do you lose any lift in turning?
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snoopy
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Post by snoopy »

We where limited to a 5 ft wingspan- we'd love to have a bigger wing than that, but that would be against the rules.... and Ded we expect the fuselage to be contributing to the lift of the wing.

The stall is nasty. If you let it properly stall, it rolls out of it, because we designed our wing to all stall at the same time. In terms of losing lift in bank, it isn't extraordinarily bad... of course it happens, but hey. Overall stability-wise, it's positively stable, has enough control (the roll is a little sluggish, but the next plane will have upsized aelerons)... really the only thing that's really weak right now is rudder- that will improve a bit next plane, but will probably remain mostly useless- since we have sufficient roll control, it isn't a problem. We've located ideal cg location, and we're pretty much ready to start trying to push it to the limit.
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Post by MD-2389 »

Now when I see stuff like this, I try to ask one key question. When do we get to see you blow it to smithereens?! ;)
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