Soaring vs. Flapping

OK, how long before we can employ this in homebuilt aircraft?

Dan, U. S. Airforce, retired

I wouldn't recommend it, as flutter is a BIG problem with flexible
wings, tails, fins, etc.

The safety issues outweigh any performance gains here for a homebuilt --
especially for a high-performance one.

I think flexible winged craft could be safer. A really flexible and
evenly-tapered wing, gradated from high to low density toward the
core, would bend to allow its force to be spread over a large enough
area to keep the force constant. A wing suit with both arm and leg
wings would enable a person to "run" through the air, except that the
motion would be closer to doggy paddling. Flying would be easier than
scrambling up a flight of stairs on all fours. See the
"SphericonWing" design at my webpage:
http://patricktimony.tvheaven.com/photo3.html

Patrick Timony

patrick timony wrote:

I think flexible winged craft could be safer.

Most wings flex to some extent, and the flexibility
serves the structural purpose you mentioned. There's
a big difference between flex for load alleviation
and flex for control, however.

Dave 'flex2rigid' Hyde

"patrick timony" wrote in message
om...
OK, how long before we can employ this in homebuilt aircraft?

Dan, U. S. Airforce, retired

I wouldn't recommend it, as flutter is a BIG problem with flexible
wings, tails, fins, etc.

The safety issues outweigh any performance gains here for a homebuilt --
especially for a high-performance one.

I think flexible winged craft could be safer. A really flexible and
evenly-tapered wing, gradated from high to low density toward the
core, would bend to allow its force to be spread over a large enough
area to keep the force constant. A wing suit with both arm and leg
wings would enable a person to "run" through the air, except that the
motion would be closer to doggy paddling. Flying would be easier than
scrambling up a flight of stairs on all fours. See the
"SphericonWing" design at my webpage:
http://patricktimony.tvheaven.com/photo3.html

Patrick Timony

Kid, get your HEAD OUT OF THE CLOWDS. Man does not have enough strength to
support or directly control flight loads. If he did, someone else would
have done it by now.

This is a sophisticated group, with much knowledge and experience on making
flying machines, and man's muscles are used via mechanical advantage only,
to direct flight, not support or sustain it.

Make a deal with yourself. Build an airplane or two, then try building
whatever you want to dream up. Then, you will clearly see what the problems
and solutions are.
--
Jim in NC

Morgans wrote:
"patrick timony"...
I think flexible winged craft could be safer. A really flexible and
evenly-tapered wing, gradated from high to low density toward the
core, would bend to allow its force to be spread over a large enough
area to keep the force constant. A wing suit with both arm and leg
wings would enable a person to "run" through the air, except that the
motion would be closer to doggy paddling.

Kid, get your HEAD OUT OF THE CLOWDS. Man does not have enough strength to
support or directly control flight loads. If he did, someone else would
have done it by now.

This is a sophisticated group, with much knowledge and experience on making
flying machines, and man's muscles are used via mechanical advantage only,
to direct flight, not support or sustain it.

Yea, and man doesn't have enough muscle to lift a thousand pounds of
dirt in one load, which is why he invented the backhoe.

You could make a man-powered suit with power assist, ala power steering,
power brakes, or any other number of analogies. It just takes smaller
power sources and actuators, and we're moving in that direction. Keep
the dream alive.

Here's a sort of rigid/flexible concept that works now.
http://www.freewing.com/

Mike "never say never" Y.

"nafod40" wrote
Yea, and man doesn't have enough muscle to lift a thousand pounds of
dirt in one load, which is why he invented the backhoe.

You could make a man-powered suit with power assist, ala power steering,
power brakes, or any other number of analogies. It just takes smaller
power sources and actuators, and we're moving in that direction. Keep
the dream alive.

Here's a sort of rigid/flexible concept that works now.
http://www.freewing.com/

Mike "never say never" Y.

Let's see, if we have a power steering type assist, and then we need power
to run the assist, then that means we need a power source, like an engine.
Do we still have man powered flight?

NOPE

By the way, anyone seen one of those man powered, power assisted flying
units at your airport? Come on now, there must be at least one out there
somewhere.
--
Jim in NC

"I think there is a man powered airplane somewhere. I remember reading
that a college class had built it to meet a challenge of flying a 1/4
mile (or thereabouts) course. It looked like a giant ultralight with a
huge wingspan and was powered by a man (in very good shape) using a
pedal system to drive the propeller. Totally impractical as a flying
machine, but interesting anyway. Perhaps someone in the group will
remember more about this accomplishment.
Mike

In article ,
(Mike) wrote:

"I think there is a man powered airplane somewhere. I remember reading
that a college class had built it to meet a challenge of flying a 1/4
mile (or thereabouts) course. It looked like a giant ultralight with a
huge wingspan and was powered by a man (in very good shape) using a
pedal system to drive the propeller. Totally impractical as a flying
machine, but interesting anyway. Perhaps someone in the group will
remember more about this accomplishment.
Mike

About 20 years ago I helped (in a very small way) on the Icarus Project,
which was the successful man-powered flight from Crete to Santorini, a
distance of about 70 miles.

Unfortunately, the craft was lost in the surf on a nude beach at
Santorini, so only a few artifacts survie. I saw a couple of them in a
display case at Silver Hill a couple of years ago.

"Mike" wrote in message
m...
"I think there is a man powered airplane somewhere. I remember reading
that a college class had built it to meet a challenge of flying a 1/4
mile (or thereabouts) course. It looked like a giant ultralight with a
huge wingspan and was powered by a man (in very good shape) using a
pedal system to drive the propeller. Totally impractical as a flying
machine, but interesting anyway. Perhaps someone in the group will
remember more about this accomplishment.
Mike

You're thinking about the Gossamer Condor, which won the Kremer 50,000 pound
prize for flying over a figure 8 course 1977, followed by the 1979 crossing
of the English Channel to win the Kremer 100,000 pound prize by the Gossamer
Albatross.
Both were designed by Paul MacCready Jr and piloted by Bryan Allen.

Only impractical in that Bryan Allen was a trained cyclist whereas most of
us are not.
Both amazing design and athletic feats.

At the time of the challenge, the Gossamer Condor weighed 70 pounds, the
pilot weighed 137 pounds.
Wing span: 96 feet
Wing area: 760 sq ft.
Aspect ratio: 12.8
The wings were covered with 1/2 mil mylar sheet on top and 1/4 mil mylar
sheets on the bottom.
Canard area 93 sq ft.
Length: 30 ft.
Height 18 ft.
Prop diameter: 12 ft.

The total flight path was 1.35 miles, while the Kremer circuit itself was
1.15 miles flown in 6 minutes and 22.5 seconds for an average speed of 10.82
miles per hour.

Don't have the figures for the Gossamer Albatross handy right now.

Eric

In article ,
Mike wrote:
"I think there is a man powered airplane somewhere. I remember reading
that a college class had built it to meet a challenge of flying a 1/4
mile (or thereabouts) course. It looked like a giant ultralight with a
huge wingspan and was powered by a man (in very good shape) using a
pedal system to drive the propeller. Totally impractical as a flying
machine, but interesting anyway. Perhaps someone in the group will
remember more about this accomplishment.
Mike

There's the "Gossamer Albatross", that, in 1979 managed a *man*powered*
flight across the English Channel. details available via google.

In article ,
(Robert Bonomi) wrote:

In article ,
Mike wrote:
"I think there is a man powered airplane somewhere. I remember reading
that a college class had built it to meet a challenge of flying a 1/4
mile (or thereabouts) course. It looked like a giant ultralight with a
huge wingspan and was powered by a man (in very good shape) using a
pedal system to drive the propeller. Totally impractical as a flying
machine, but interesting anyway. Perhaps someone in the group will
remember more about this accomplishment.
Mike

There's the "Gossamer Albatross", that, in 1979 managed a *man*powered*
flight across the English Channel. details available via google.

In addition, there was the Daedalus, which flew man-powered, from Crete
to Santorini. I knew some of the principals and even did a little work
on it. These guys were mostly MIT grads an really had their low-speed
aero in hand. Unfortunately, all that is left of the craft is in a small
display case at Silver Hill (pedals, gearbox and a few miscellaneous
pieces), as the craft landed in the surf at a nude beach and broke apart.