human powered flight

Is anyone experimenting with human powered flight based on flapping
wing aerodynamics (hovering wing motion rather than soaring)? I have
a number of ideas and would love to exchange thoughts on the subject.
Some of them are as follows:

Materials: light, strong, sandwich-layered foam like Voltec's
mini-cell.

Leg wings, Power tail or Body fin (like a ray).

Wing shape based on rounded 3x5 rectangle with leading edge curled
down and trailing edge curled up.

Wing design using tapering Spirals intead of sharp angles.

Crawl or Doggypaddle style stroke rather than Butterfly.

Standing take-off, like a pidgeon.

Figure "8" wingstrokes (no upstroke) so force is distributed over
whole stroke.

If anyone has tried any of these or has any coments, please contact
me.

A good friend tried that some 30 plus years ago. He tells a great story.
It seems that his machine had a single driving wheel to help get up to
speed. Unfortunately, it wasn't quite adequate so they decided to tow
it to get the speed just a little higher.

His comment, and I quote:

Dennis, have you ever tried to tow a unicycle?




In article ,
(patrick timony) wrote:
Is anyone experimenting with human powered flight based on flapping
wing aerodynamics (hovering wing motion rather than soaring)? I have
a number of ideas and would love to exchange thoughts on the subject.
Some of them are as follows:

Materials: light, strong, sandwich-layered foam like Voltec's
mini-cell.

Leg wings, Power tail or Body fin (like a ray).

Wing shape based on rounded 3x5 rectangle with leading edge curled
down and trailing edge curled up.

Wing design using tapering Spirals intead of sharp angles.

Crawl or Doggypaddle style stroke rather than Butterfly.

Standing take-off, like a pidgeon.

Figure "8" wingstrokes (no upstroke) so force is distributed over
whole stroke.

If anyone has tried any of these or has any coments, please contact
me.

In article ,
(patrick timony) wrote:

Is anyone experimenting with human powered flight based on flapping
wing aerodynamics (hovering wing motion rather than soaring)?


I think Iccarus and Dadealus tried it. Leonardo Devinci drew pictures of
his ornithopter. If you watch the start of "Those Magnificent Men in
Their Flying Machines you will see short clips of ornithopters. They
didn't work.

One reason this does not work is because humans do not have the strength
to weight ratio for muscle powered flight. Birds are specialized. Even
their skeleton is porous so the bones are lighter.

Bernadette

: One reason this does not work is because humans do not have the strength
: to weight ratio for muscle powered flight. Birds are specialized. Even
: their skeleton is porous so the bones are lighter.

The human-powered planes that have crossed the English channel
required something like 2.5 HP (about 2000 Watts). That's about the most
efficient plane you can make that'll carry a person. Try peddling like
2.5 horses for more than a few minutes and see if you'd like to "land" yet

-Cory
--
************************************************** ***********************
* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
************************************************** ***********************

wrote in message
...
: One reason this does not work is because humans do not have the strength
: to weight ratio for muscle powered flight. Birds are specialized. Even
: their skeleton is porous so the bones are lighter.

The human-powered planes that have crossed the English channel
required something like 2.5 HP (about 2000 Watts). That's about the most
efficient plane you can make that'll carry a person. Try peddling like
2.5 horses for more than a few minutes and see if you'd like to "land" yet

-Cory
--
************************************************** ***********************
* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
************************************************** ***********************
You're off by an order of magnitude. The Gossamer Albatross flew on 1/4 to
1/3 hp.
See "Gossamer Odyssey" by Morton Grosser for lots and lots of details.

Tim Ward

wrote:

The human-powered planes that have crossed the English channel
required something like 2.5 HP (about 2000 Watts). That's about the most
efficient plane you can make that'll carry a person. Try peddling like
2.5 horses for more than a few minutes and see if you'd like to "land" yet

-Cory

More like 0.4 hp (300 Watts) or perhaps even a bit less, Cory. The
best Olympic caliber endurance athletes max out at about 0.6 hp (450
Watts) of sustained power output. My 380 (or so) Watts got me to the
to the US Olympic cycling trials in 1976 but I didn't make the team.

At 50, I still storm my 30 year old racing bike over the mountains of
north Georgia, but my extraordinary aerobic capacity went south about
10 years ago, along with my reading vision.

David O -- http://www.AirplaneZone.com

David O wrote:
I stand corrected. I recall hearing that number (1hp) on some
special and thought it was extremely unlikely. You gotta admit that even
1/3 hp for a long time would be a serious workout. People tend to not
have a feeling for how much power a light bulb takes until they work on a
treadmill.


: More like 0.4 hp (300 Watts) or perhaps even a bit less, Cory. The
: best Olympic caliber endurance athletes max out at about 0.6 hp (450
: Watts) of sustained power output. My 380 (or so) Watts got me to the
: to the US Olympic cycling trials in 1976 but I didn't make the team.

: At 50, I still storm my 30 year old racing bike over the mountains of
: north Georgia, but my extraordinary aerobic capacity went south about
: 10 years ago, along with my reading vision.

: David O -- http://www.AirplaneZone.com



--
************************************************** ***********************
* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
************************************************** ***********************

Earlier, wrote:

The human-powered planes that
have crossed the English channel
required something like 2.5 HP
(about 2000 Watts).

No, I don't think that that's right. I believe that both the Gossamer
Condor and the later channel-crossing Gossamer Albatross took only
about 1/3 horsepower (about 250 watts) to stay in the air.

Bob K.

wrote in message ...
: One reason this does not work is because humans do not have the strength
: to weight ratio for muscle powered flight. Birds are specialized. Even
: their skeleton is porous so the bones are lighter.

The human-powered planes that have crossed the English channel
required something like 2.5 HP (about 2000 Watts). That's about the most
efficient plane you can make that'll carry a person. Try peddling like
2.5 horses for more than a few minutes and see if you'd like to "land" yet

-Cory

I think the HPOs like the English channel one, require so much energy
because they are not using their weight efficiently. The style of
natural flight they are trying to imitate is soaring. I am talking
about hovering flight like a bumble bee or a humming bird or a
butterfly. The butterfly is really important I think because it has
low aspect ratio wings and if you watch them you can see that they're
moving just like a swimmer doing the "butterfly", which is sort of how
I think a human powered stroke would have to work. But I think we are
built more for the crawl stroke or a combination of the breast stroke
and the crawl, becuase our legs are so much more powerful and the leg
stroke would have to support most of our weight. I think the stroke
that would work best would be one that allows the flyer to adjust the
speed and style of each limb to support his body maintaining a certain
position in the air. This would probably look like three dimensional
running. Actually it would probably look pretty much like an
exagerated doggy paddle, if you've ever seen a dog swimming in place
in the water.

All the Ornithopters I have seen on the net are using bird=like or
dragonfly=like wings. I think they should lower their aspect ratios,
start thinking about vertical take off, and use curves, concave
surfaces, and even spirals in their wing design.

Patrick

"patrick timony" wrote in message
m...
wrote in message
...

I think the HPOs like the English channel one, require so much energy
because they are not using their weight efficiently. The style of
natural flight they are trying to imitate is soaring. I am talking
about hovering flight like a bumble bee or a humming bird or a
butterfly. The butterfly is really important I think because it has
low aspect ratio wings and if you watch them you can see that they're
moving just like a swimmer doing the "butterfly", which is sort of how
I think a human powered stroke would have to work. But I think we are
built more for the crawl stroke or a combination of the breast stroke
and the crawl, becuase our legs are so much more powerful and the leg
stroke would have to support most of our weight. I think the stroke
that would work best would be one that allows the flyer to adjust the
speed and style of each limb to support his body maintaining a certain
position in the air. This would probably look like three dimensional
running. Actually it would probably look pretty much like an
exagerated doggy paddle, if you've ever seen a dog swimming in place
in the water.

All the Ornithopters I have seen on the net are using bird=like or
dragonfly=like wings. I think they should lower their aspect ratios,
start thinking about vertical take off, and use curves, concave
surfaces, and even spirals in their wing design.

Patrick

Have you ever seen a three-hundred pound butterfly?

Butterflies fly very nicely down in the low Reynolds number regime -- where
the air behaves more like honey -- using the "clap - fling - ring"
mechanism.
Their wings touch at the top of the stroke (the "clap"), then are peeled
briskly away from each other to start the circulation around the wing (the
"fling"), and at the bottom they touch again, shedding a vortex ring
downward (the "ring"), which pushes them upwards. They may or may not hold
the wings out midway on the upstroke for a short, fairly steep (but low sink
rate) glide.
This flight mechanism is why their flight path looks so erratic.

Other insects have waxy pads on the bottoms of their feet and can walk on
the surface tension of the water. But buttering up your tootsies won't let
_you_ walk on water, because some things just don't scale.

Tim Ward