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Jun 03, 2019, 11:07 AM
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Nemeth Parasol - Almost a Nutball


Got bored and whipped this up over the weekend.

Based on the original Nemeth Parasol - one of the original STOL aircraft designs.

Circular Wing Monoplane 250001-11 (0 min 44 sec)


2 sheets of DTFB, 3x9g servo's , 2208 motor on plastic X_mount and a 12A ESC

Haven't had a chance to fly it yet (still need some finishing touches, like wheels)

The original had what appears to be ailerons and one massive flap on the wing. Didn't realize that until now, so I'll have to make another wing. Mine just has ailerons.
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Jun 04, 2019, 05:07 AM
gpw
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“There’s no place like Foam”
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COOL !!!
Latest blog entry: Lost plans
Jun 04, 2019, 08:46 AM
I Look, Listen, and Learn
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Don't forget video if you can. I didn't get a good look at it in the other thread and I am curious if that X style fuse and the large wheel pants will affect the flight some.....it's going be interesting to watch this fly.
Jun 04, 2019, 11:34 AM
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Yeah I'm just debating on motor.

2208 w/ a 12A x 8" prop or 2212 w/a 30A x 10" prop (if it will fit)
Jun 10, 2019, 10:48 AM
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I need to start taking my gopro to the field with me LOL.

"technically" - it flew.

The "X" type fuselage out of DTFB exhibited a weak point right below the front of the wing mount, and snapped in half pretty cleanly.

I only made a 20" diameter "wing" which I think was just a hair to small for the overall size and it had a bad tendency to roll right. Got it about 5 feet off the ground, then it just rolled over and in, so that ended that adventure.

Wing survived, so it'll become another nutball LOL.
Jun 10, 2019, 09:11 PM
I Look, Listen, and Learn
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Are you giving up on it already? Or are you just going build a totally new one?
Jun 11, 2019, 05:38 AM
gpw
gpw
“There’s no place like Foam”
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Maybe try again in a little bigger size … and with a little beefier construction on the known weak areas…
I wouldn’t blame the design as yet … It “ should “ be very stable

In fact , I believe those wide landing gear fairings might be acting as a forward vertical surface leading to directional instability … Just a WAG !!!
Latest blog entry: Lost plans
Jun 11, 2019, 05:47 AM
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Quote:
Originally Posted by Brett_N
I only made a 20" diameter "wing" which I think was just a hair to small for the overall size and it had a bad tendency to roll right. Got it about 5 feet off the ground, then it just rolled over and in, so that ended that adventure.
So that sounds like classic torque roll, probably made worse by the super low aspect ratio of the disc relative to the airplane size.
A larger disc with appropriate trim (to counter a any roll tendency) should solve the problem.
There have been quite a few successful "Star Trek Enterprise" builds right here on this site, which have a big disk with various appendages attached to it - essentially the same overall idea as this plane.
Jun 12, 2019, 11:26 AM
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No not giving up on it - In fact I'll probably just glue the nose back on, add some BBQ Skewers and make a bigger "wing" Everything else is still intact but I donated the ESC so I'll have to dig another one out of the parts bin.

What's funny is I said "roll right" and then I'd 100% agree with torque roll - but - it was rolling LEFT (typing mistake) so it was probably trim.

I may ditch the landing gear altogether as well.
Jun 12, 2019, 04:16 PM
gpw
gpw
“There’s no place like Foam”
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Check for warps too … even round wings can get warps ( ask me how I know )

And here’s a secret … try launching at a lower power …Full power launches can quickly get quite dramatic , full torque in play , and the bigger the prop , the More the torque ...
just something else to try ...
Latest blog entry: Lost plans


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