Rotary-wing Ultralight Aircraft

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Aviator168

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henryk,

I doubt such a small rotor (propella size) can generate much lift.
BTW, can you explain the mechanism? I can't quite form a visual of how it works.
 

henryk

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henryk,

I doubt such a small rotor (propella size) can generate much lift.
BTW, can you explain the mechanism? I can't quite form a visual of how it works.
see #20 = < 1 kW battery power=15 kG thrust... >15 kG /kW specific thrust !!!

=NO gear (CRFLIGHT-like) , NO reaction and gyroscopic momentum ...

-the best system for prerotation and drive CR rotors in fly=lower fuel consumption,
aspatialy in E-drive gyrocopter...

=in case of "empty" batteries it can fly as gyro-glider !

 

henryk

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Let me get this straight. The small propeller blows air down that causes the rotor to turn. Is that right? How is the torque get cancel?
=no,motor shaft (rotor) driwe one propeller,
second propeller is drived via crankcase (stator)

from 1921 !=

-bis yet=
 
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jedi

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I have a model helicopter from many years ago that used a small glow engine (next size down from an .049) in a similar setup. The smaller prop down wash fills in the center area where the larger helicopter blade has an up wash. Torque of the two rotors is equal so no tail rotor is needed. power is split in the ratio of the rotor rpms so prop gets most of the power affecting efficiency.

In Henryk's example the rotor is pitched for an autogyro so the rotor can have some power assist as well as a prerotor. It is an interesting concept. Looking forward to flight test reports.

My three and a half year old granddaughter needs one of those flying dolls and the pixi wing costume to go with it.
 

Brünner

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........

My three and a half year old granddaughter needs one of those flying dolls and the pixi wing costume to go with it.
Are you gonna build one?
Looking forward to the building log for that....mmmaybe.
 

Brünner

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=we have discover strange sytuation=iff to stop dolly by head,she stay stabilly in air,
but iff to stop via futh ,she became unstability !

="negative stability"...

analogical sytuation in HILLER PLATFORM=
Perhaps because the head is the heavier body part (even for dolls)?
 

Sockmonkey

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Perhaps because the head is the heavier body part (even for dolls)?
Ah, I see how that works. It's like when you balance a stick vertically in your hand. The inertia of the head means it moves slower than the base when the tilt makes the thrust move it sideways so the bottom automatically centers itself under the CG. Clever.
 

jedi

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Are you gonna build one?
Looking forward to the building log for that....mmmaybe.
No.

I am going to go to Target or where ever they are sold. I can't get it from Amazon cause they won't take the $29.95 in my pocket.

Oh. I just found out that I have an extra $2,800 virtual dollars in my bank account.

=we have discover strange sytuation=iff to stop dolly by head,she stay stabilly in air,
but iff to stop via futh ,she became unstability !
That is physics at work. Physics works regardless of if or how you can explain it.

Economics works weather you understand it or not also. Virtual dollars evaporate if not spent quickly.

Where can I purchase a full size flying doll for $2,8000 virtual dollars.? I want one of those. I did the build for a full size doll 39 years ago but she doesn't fly even though she had a Cessna 310 when she was three years old. (Sorry no build log for that. You will need to figure that out on your own.)

I am still working on the personal flying machine aspect. The Cessna was too big and noisy and was no fun for a three year old to fly in. IF I can plant the bug in my three and a half year old granddaughter perhaps she will want to fly something smaller and funner. She demonstrates a lot of potential. Her dad is the creator of the poster of post #229 of Page 12 of the control thread. Sidestick control vs control yoke vs panel-mounted control wheel and the earlier post in the affordable ultralight thread. Post 174 page nine of the what-is-an-affordable-ultralight. thread (What is an affordable ultralight?)

1616421243400.png

The vertical takeoff like the doll is a little further down the road. FWIW I am watching the humming birds closely and trying to learn from them.
 
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henryk

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jedi

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hummingbirds


=Yves Rousseau...
How hummingbirds fly - BirdWatching

"Resourceful hummingbirds took to the air and rewrote the book on flight. They combine speed with endurance."

The goal of today's E-VTOL aircraft development as demonstrated by the Nastya video. Henryk is right to look towards the work of Yves Rousseau. IMHO we must progress from rotating to oscillating propulsion with the correct Strouhal number to maximize the speed and range as desired with the limited battery technology available.

Very sorry for the unfortunate accident of Yves Rousseau.
 
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henryk

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towards the work of Yves Rousseau.

=many,many attemts...

Vladimir Toporovs group from Votkinsk was achived the best results...(man-powered AZAZEL
and engine (20 HP) powered ISTINA.)



=Adalbert Schmid was involve effective rotational thruster into sailplane (hybrid !)
 
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henryk

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Looking forward to flight test reports.
-we have made little test with 4 + 7 m rotors drived via 154120 motor +3:1 planetary
integrated reductor...

=they was conterrotated wery well,
but at 10 kW power (100 V * 100 A) motor have some coils demage (bad isulation !).



=Nagler helis... (# 51)
now we are oldmanes,not good time for follow this (very promissing) experyment ...
 

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