Clearly Outside the Box

On Jul 20, 3:40*pm, bagmaker
wrote:
Where is the door?

--
bagmaker

Through the hole in center of the electric motor. It's like the old
science demonstration for getting a hard boiled egg into a soda
bottle. Throw in a small piece of burning paper to use up the oxygen
and reduce the internal pressure by enough to "thwump!" suck the egg
in. Getting out, well that's a different matter.

It is good to have new designs, but this one isn't a good idea or the
least bit practical. It takes a lot of energy and CARBON to make
molds for the polycarbonate fuselage. So far I do not know of any
facility who can make such a massive injection molded part. Maybe
scale this down to a toy and it will be available at Walmart for
$19.95. Competely ridiculous.

Discus 44 wrote:
It is good to have new designs, but this one isn't a good idea or the
least bit practical. It takes a lot of energy and CARBON to make
molds for the polycarbonate fuselage. So far I do not know of any
facility who can make such a massive injection molded part.

That would not seem necessary. Perhaps it could be blow or spun molded,
or built from several large pieces glued or welded together. More to the
point, I think, is the suitablity of the material in the first place:
without fiber reinforcement, I think it might be too heavy.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

On the UAV project I was involved in the finacier decided the time
frame and the cost was too great for the traditional mold-part
process. He got ahold of a friend in the polycarbonate/stratch form
biz and was convinced this was the way to go.

$15,000 later we got floppy parts that were to heavy and impossible to
trim.

Brad


On Jul 21, 9:20*am, Eric Greenwell wrote:
Discus 44 wrote:
It is good to have new designs, but this one isn't a good idea or the
least bit practical. *It takes a lot of energy and CARBON to make
molds for the polycarbonate fuselage. *So far I do not know of any
facility who can make such a massive injection molded part.

That would not seem necessary. Perhaps it could be blow or spun molded,
or built from several large pieces glued or welded together. More to the
point, I think, is the suitablity of the material in the first place:
without fiber reinforcement, I think it might be too heavy.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes"http://tinyurl.com/y739x4
* * * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" atwww.motorglider.org

On Jul 20, 2:22*am, ContestID67 wrote:
I agree that this is "out of the box" thinking...

Don Lancaster has written that ideas are not a dime a dozen--rather
more like a dime a bale in hundred-bale lots.

As for structural uses of polycarbonate, that can be made to work fine
just so long as you understand the fundamental difference between
strength and stiffness.

The general rule of thumb for PV solar cells is that you can expect
1KW/m^2 of area, but only if the sun is high (less atmosphere to
penetrate) and the cells are oriented normal to the sun. So the
exposed area of a typical 15m ship of S=10m^2 might yield 10KW (just
over 13 horsepower) under once-in-a-turn conditions, and maybe average
40% of that, around 5 horsepower, over a sunlit day. I can see that
working for a highly-optimized single-seater. Heck, I've been to the
ESA Western Workshop enough times to actually see it work for a
specific highly-optimized single-seater. But for a less finely-
optimized 2-seater, probably not so much.

BTW and somewhat off-topic, in the latest update of his Energy
Fundamentals paper, Lancaster suggests that PV solar might actually
not be a net energy sink, and proposes a figure of $1/installed watt
as the break-even threshold. Heck, that might even be doable.

Thanks, Bob K.

{Quote from article}
A plane with [a] reinvented lifecycle based on the Cradle-to-Cradle
principle. It combines an ecological energy concept and sustainable
materials, with an organic design language and bionic inspired
details”.

Cernat’s concept is governed by a “designed-for-disassembly”
philosophy based upon the Cradle-to-Cradle ideals, thus all of its
materials are easily recyclable. The glider’s frame is constructed out
of a lightweight flax bio-compound that is CO2 neutral, recyclable...
{end quote}

sounds just like my Cherokee! except that before my glider was a
glider it actually took CO2 OUT of the atmosphere and replaced it with
Oxygen. In fact, depending on how old growth the wood is, a lot of
could be flying Carbon Positive aircraft!