Low aspect ratio sport plane ideas

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bl_dg

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OK - so thinking about building a 1/4 scale model for testing. Suggestions and input regarding 1/4 scale testing appreciated. (i.e. weight of the model compared to design MTOW.)

Prop on the front, cockpit details not worked out. 19' x 12' span. Model would be about 5' x 3' span.

Capture1.PNG
 

Vigilant1

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cluttonfred

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OK - so thinking about building a 1/4 scale model for testing. Suggestions and input regarding 1/4 scale testing appreciated. (i.e. weight of the model compared to design MTOW.)

Prop on the front, cockpit details not worked out. 19' x 12' span. Model would be about 5' x 3' span.

View attachment 125659

For something like that to balance with varying pilot weights I think you’d need the pilot sitting at about 25% chord so your firewall for a tractor engine installation would be at the joint in the fuselage. In other words, lose the whole pointy front bit and put the engine there.
 

nestofdragons

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OK - so thinking about building a 1/4 scale model for testing. Suggestions and input regarding 1/4 scale testing appreciated. (i.e. weight of the model compared to design MTOW.)

Prop on the front, cockpit details not worked out. 19' x 12' span. Model would be about 5' x 3' span.

View attachment 125659
Looks familiar.
Oh Yes ...
download (1).jpg
;)
👍
 

WonderousMountain

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Okay, so basically I ruined the math formula previously here.

For a Quarter scale equivalence you need 1/16th the wing load, Dynamic. Taken together, with surface area that's 1/16th target, you will use 1/16th your ideal gross weight in Oz of pounds, if Units are Imperial variant
 
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bl_dg

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Can’t seem to get the multi-quote working, so here goes:

TT - Who else remembers flying on Pan Am (or TWA)? .👍
V1 - Thanks, just what I was looking for! 🍻
VH9 - Wings level and pointy end forward is a good day.
R618 - Thanks, vortex lift might not be enough!
Fred - Mini-Imp, BD-5, Bugatti 100P. 💡
NoD - Oooh, BSG! Cockpit location works, room for auxiliary pulse jets, guns on the L/E strakes… Viper Mk7
WM - Yikes! At 800 lbs, I would be a lawn dart.

Thanks all for the replies.
 

J.L. Frusha

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I recall a Russian fella came to Oshkosh ‘91 (+ /-2 yrs) with what he called a “suitcase airplane” because it folded up into a wicked small package (on purpose, not like a cartwheeling Ercoupe). Even Tom Poberezny was impressed with the plane and was touting it to the masses. I never heard any more about/from him, though.

A member of this forum has it and it's not on any timeline to be resuscitated. The X-14
 

J.L. Frusha

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I shot him an email. Hard to believe it has been over a decade since I was in communication with him...

It has long since been returned to Victor. I would guess it is somewhere behind the Iron Curtain...

Perhaps it is time to revive the concept, with fewer moving parts and far less complicated controls...?
 

bl_dg

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Very nice article on the two place Verhees Delta, the D2 in the July Kitplanes magazine. cool pics and diagrams as well.

Excellent article, especially the Power vs Speed curves. So with delta (LAR) aircraft, the slower you go, substantially more power is needed. And if you add more area, then you need more power to go fast. Seems like this platform is better suited for something that’s designed to go fast, not slow. (Like a lawn dart!) Not that you couldn’t use it for low-n-slow, as long as you have sufficient power.
 

berridos

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Would love to understand why the central bottom section looks like an inverted airfoil. Bart is really innovative
 

nestofdragons

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Yesterday i was curious. What if i used a airfoil which has a more backward thickest part in airfoil. I wanted to see that would happen to the needed glass parts for good vision. At this moment i was still thinking about a fat wing to house the pilot. Soon i might change my interest to thinner wings to get higher speeds.
5EBABF2D-D5D6-4979-B2F0-7826CABAF67B.png
you can see that the pilot can nearly look over the topside of the wing towards the ground. The Horten and Fauvel airfoils are too fat at the front to achieve this.
image.jpg
blue is NM-62 which i now used in my latest 3D. Orange is Horten at 20%. Grey is Fauvel 20%. NM-62 by Norman Masters has indeed a more backwards fat part in airfoil. X and Y are not having same dimensions here. So the shape may look fatter or thinner than normal.
i had little time to make 3Ds. So i simply kept the 19% thickness of the airfoil over the entire wing. Yes, it became a chubby wing.
i share a few other views on latest draft.
Soon i start drawing thinner wings. I hope to get a cool shape around that idea.
83A6A3D8-89D9-4FDB-A5E8-4964E98E46C2.png
E30EEDEC-3939-4D50-9679-C304B96DEE1E.png
74896126-1AEE-4E95-AC37-9B6BD419A002.png
81EBE1D4-3284-4E14-93BF-827658D9F8F2.png
554D3D5A-7425-4B84-A619-CD41543645E6.png
in these drafts the 25% chord underside are all at same height. If i wanted to install elevators or dragrudders in main wing, that would be possible as there are only 3 steps in the half wing.
 
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bl_dg

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Feb 12, 2013
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Yesterday i was curious. What if i used a airfoil which has a more backward thickest part in airfoil. I wanted to see that would happen to the needed glass parts for good vision. At this moment i was still thinking about a fat wing to house the pilot. Soon i might change my interest to thinner wings to get higher speeds.
View attachment 125814
you can see that the pilot can nearly look over the topside of the wing towards the ground.
View attachment 125816
Nice work. Yes, looks like you could go thinner on the wing, down to the knee and shoulder level. Maybe make the cockpit/canopy slightly wider at the shoulder level.

Just curious - what is your target MTOW, wing area and cruise speed?

Have you thought about moving the rudders further back, like the early Rutan designs, with the rudder aft of the trailing edge?4595499B-9BE7-44FB-861D-44AA986ECD0F.jpeg
 
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