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Old Nov 24, 2014, 02:00 AM
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Human powered ornithopter

Human powered ornithopter
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Old Nov 29, 2014, 05:03 AM
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Old Nov 29, 2014, 07:14 AM
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In general, due to the power/wt "problem" of humans [vs creatures & machines specially evolved/designed for self-flight], it seems obvious that the only real way to have human-powered flapping flight is to store energy pre-flight. Or while gliding.

The storage can be electrical/chemical [rechargable batteries] or mechanical [compressed air], etc.

MANY solar powered special-purpose cars use this technique, storing solar-electrical power while stationary and "resting" before starting off!

Else the only human-power will be restricted to running before taking off from a cliff/mesa as a non-flapping glider.
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Old Nov 29, 2014, 04:10 PM
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Lee is right.
Quetzalcoatlus northropi is similar in size and weight to a human powered glider (330 pounds, 36 foot wingspan). Gliding performance is slightly better than an albatross, but Quetzalcoatlus has 25 to 30% flight muscle vs. total weight and still has to flap about 85% of the time when operating as a flap-glider in no-lift conditions (when unable to extract lift from the atmosphere). So, a human powered ornithopter a little more efficient than an albatross would require about 90 pounds of human flight muscle to stay aloft.
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Old Nov 30, 2014, 04:15 AM
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Unlocking mechanism - variant
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Old Nov 30, 2014, 05:40 AM
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Originally Posted by JimC3 View Post
... and still has to flap about 85% of the time when operating as a flap-glider in no-lift conditions (when unable to extract lift from the atmosphere).
I have not observations of Quetzalcoatlus flight.
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Old Nov 30, 2014, 06:15 AM
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The only so-far successful human-powered flying has been done by Olympic-class bicyclist athletes flying [driving!] huge ultra ultralight fixed-wing aircraft .... in GROUND EFFECT. Which is not "really" flying! The ground effect extends one-half wingspan above the surface, which is why the huge wingspan was needed to overcome the Kremer prize minimum flying-height requirement.

Further, the propeller-propulsion is far more efficient than flapping and it obviously impossible for living creatures to have rotating shafts/axles, although a hummingbird's "shoulder" starts to approach that, but within a cone much reduced from true 360 rotation.

http://en.wikipedia.org/wiki/Human-powered_aircraft

http://archives.chicagotribune.com/1...s-by-own-power
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Old Nov 30, 2014, 06:37 AM
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The thread is HUMAN POWERED ORNITHOPTER
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Old Nov 30, 2014, 07:01 AM
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and ....?
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Old Nov 30, 2014, 07:05 AM
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Quote:
Originally Posted by xlcrlee View Post
The only so-far successful human-powered flying has been done by Olympic-class bicyclist athletes flying [driving!] huge ultra ultralight fixed-wing aircraft .... in GROUND EFFECT. ]
And also Human Powered Helicopter
Atlas Human-Powered Helicopter - AHS Sikorsky Prize Flight (1 min 45 sec)

Of course within Ground Effect
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Old Nov 30, 2014, 07:08 AM
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The thread is HUMAN POWERED ORNITHOPTER
And the forum is about RC
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Old Nov 30, 2014, 07:12 AM
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Very sorry for any and all confusion or misunderstanding, Velko, but my "point" was clearly, very clearly stated in Post #3 and confirmed in Post #4!

That is, regardless of how clever the mechanical and aerodynamics of any human-powered Ornithopter, until someone makes/creates a new kind of "post-human" with new and GREATLY improved muscle/wt output, the only likely way to fly such an Ornithopter will be to pre-store energy or add it during pure gliding flight .... which the operator can actually put in by him/herself [by peddling, or whatever]. Like winding a rubberband by hand in a freeflight model, as with the classic TIM-bird, which is, ultimately, HUMAN powered [assuming one does not use an electric winder!]

Lee
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Old Nov 30, 2014, 07:43 AM
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Originally Posted by nono1928 View Post
And the forum is about RC
http://www.rcgroups.com/forums/showt...ed+ornithopter
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Old Nov 30, 2014, 08:44 AM
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Originally Posted by xlcrlee View Post

Further, the propeller-propulsion is far more efficient than flapping
Props may be more powerful, but more efficient? No way.
Also, integrating prop drive system, and energy storage system worse so, adds weight and requires huge wingspan to compensate as seen in the snowbird.

Lose the prop and go to direct muscle drive and rely on running start and you can get airborne, and leave the ground behind. You should build it Velkov!

Skepticism on human powered ornithopter is very rational and well placed. However, it will be proven wrong.

Only flap when you need to
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Old Nov 30, 2014, 08:46 AM
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Originally Posted by xlcrlee View Post
and ....?
Comments ... ???
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