Amazing soaring facts?

Doug Easton wrote:
Looking for some help from the group... I'm putting together a presentation
(might be overhead viewgraphs and/or a series of posters) for the general
public on soaring and I want to catch their interest and imagination.

Still the most amazing thing in the world to me is
that I can fly, in a glider, for hours on end, WITH NO ENGINE!
Last weekend I finally had to land after 3 and a half hours because
I had to pee (I naively didn't bring any nifty relief devices).
And this in a less than $10,000 Blanik L-13! Where else in aviation
can you fly a two-seat aerobatic aircraft that spins 70 deg nose
down, has lots of space, good vis, is quiet, and costs under
$10,000 to buy and $7 a flight to rent (sure sure, plus tows :P)?

$10 an hour for flying (then split between 2 people so really
$5 an hour) is really cheap, challenging fun. And what
a challenge of skill! If you do it right, you get hours
of quiet flying long distances. If you do it wrong, you land
safely, but earlier than you wanted.

And how about selling it to parents of teenagers? With all the
teenage vices, isn't it nice to offer an alternative which
a teenager can enjoy and really learn from? I can't tell
you how many kids get really inspired by their "first flight."
Grades go up, they start liking math and science, and
the imagination soars...
--

------------+
Mark Boyd
Avenal, California, USA

"Bob Kuykendall" schrieb im Newsbeitrag
om...
Earlier, "bsquared" wrote:

I hate to disagree with you, but sailplanes
are "powered" by gravity, not the sun.

Well, we'll just have to agree to disagree, then. To say that gliders
are powered by gravity would have to involve a definition of power
with which I am not familiar.

Bob K.

Just imagine: You are flying a glider equipped with a gravity switch. So
long, as you let the gravity switch is in position "on", everything is as
usual. But what happens, if you switch the gravity off? Due to the drag, the
speed will go to zero, the controlls became ineffective and the glider will
float uncontrollable as a free balloon. It means: Without the gravity, no
gliding and no soaring is possible. What a horror imagination!!!!

George

Evals wrote:

Forgive me for disagreeing in return. On a non soaring flight, sailplanes
are powered (mostly) by the internal combustion engine. Gravity just
reclaims the energy expended by the use of fossil fuels. Any gain in height
after launch is indeed "nuclear" powered.


Actually Bob K. had it right to begin with, even on a non-soaring flight.
Where do you think those fossil fuels came from? All life on Earth derives,
either directly or indirectly, sustenance from the Sun. Plants use
photosynthesis to convert the Sun's energy into food. Animals then eat the
plants or other animals that ate the plants. And so on.

Regards,

-Doug

"George Vranek" wrote in message
...

Just imagine: You are flying a glider equipped with a gravity switch. So
long, as you let the gravity switch is in position "on", everything is as
usual. But what happens, if you switch the gravity off? Due to the drag,
the
speed will go to zero, the controlls became ineffective and the glider
will
float uncontrollable as a free balloon. It means: Without the gravity, no
gliding and no soaring is possible. What a horror imagination!!!!

George



It does make one wonder about guys who keep talking about ever lighter
gliders.

I don't want a switch that turns gravity off, I want one that tilts the
local gravity vector about 2 degrees from the vertical.

Bill Daniels

(Bob Kuykendall) wrote in message . com...
Earlier, "bsquared" wrote:

I hate to disagree with you, but sailplanes
are "powered" by gravity, not the sun.

Well, we'll just have to agree to disagree, then. To say that gliders
are powered by gravity would have to involve a definition of power
with which I am not familiar.

Bob K.

Potential energy is stored in a gravitational field by raising a mass
to an altitude. This is analogous to storing energy in a capacitor
using a voltage (height) to create an electric (gravity) field. The
heavier the mass the greater the energy (which is why we use ballast).

But the storage mechanism is not the source of the power used to lift
the mass to altitude. This (usually) comes from the Sun. I say usually
because I have used nuclear powered thermals.


Tom Seim
Richland, WA

"Mark James Boyd" wrote in message
news:4076d3b1$1@darkstar...
Doug Easton wrote:
Looking for some help from the group... I'm putting together a
presentation
(might be overhead viewgraphs and/or a series of posters) for the general
public on soaring and I want to catch their interest and imagination.

Still the most amazing thing in the world to me is
that I can fly, in a glider, for hours on end, WITH NO ENGINE!
Last weekend I finally had to land after 3 and a half hours because
I had to pee (I naively didn't bring any nifty relief devices).
And this in a less than $10,000 Blanik L-13! Where else in aviation
can you fly a two-seat aerobatic aircraft that spins 70 deg nose
down, has lots of space, good vis, is quiet, and costs under
$10,000 to buy and $7 a flight to rent (sure sure, plus tows :P)?

$10 an hour for flying (then split between 2 people so really
$5 an hour) is really cheap, challenging fun. And what
a challenge of skill! If you do it right, you get hours
of quiet flying long distances. If you do it wrong, you land
safely, but earlier than you wanted.

And how about selling it to parents of teenagers? With all the
teenage vices, isn't it nice to offer an alternative which
a teenager can enjoy and really learn from? I can't tell
you how many kids get really inspired by their "first flight."
Grades go up, they start liking math and science, and
the imagination soars...
--

Yep, we snagged a B- geology major, showed him the way forward, he graduated
as a fine student, and along the way gained Glider, Commercial Glider,
CFI-G, Power, Instrument, and is now sitting in Corpus Christi waiting for
his Navy BPT to start next month. He still likes soaring best, especially
after Gogos and George Lee's mentoring course. Now if we could just find
another 6-7 like him;^) He's bringing his roommate (CFI-G from FL) here for
a week in April for some ground launching and high country soaring. I guess
their discussions of aerodynamics at Pensacola were a bit obtuse WRT the
course material.

Frank Whiteley
Colorado

Earlier, "bsquared" wrote:

I hate to disagree with you, but sailplanes
are "powered" by gravity, not the sun.

Hello B^2,

I hate to disagree with you too. Gravity moves the glider forward and
slightly downward. The sun moves the glider upward if you as a pilot are
trained enough to use its effect on the atmosphere.
So we need gravity and the sun for our amazing nice sport.

Karel, NL

This (usually) comes from the Sun. I say usually
because I have used nuclear powered thermals.

You're referring to fission thermals, from nuclear power stations, I
take it, as distinct from the more usual thermonuclear-powered
thermals...

George Vranek wrote:
Well, we'll just have to agree to disagree, then. To say that gliders
are powered by gravity would have to involve a definition of power
with which I am not familiar.
Just imagine: You are flying a glider equipped with a gravity switch. So
long, as you let the gravity switch is in position "on", everything is as
usual. But what happens, if you switch the gravity off? Due to the drag, the

This is switching the question from "what powers gliders" to "what factors
are necessary for gliding".

Many things are necessary: Take away the air, and gliding is also not
possible, but this does not mean that gliders are powered by the air.
CV

Even the power for fission thermals came originally from a sun, just not
*this* sun.

--
Regards,

Adrian Jansen
J & K MicroSystems
Microcomputer solutions for industrial control
"Finbar" wrote in message
m...
This (usually) comes from the Sun. I say usually
because I have used nuclear powered thermals.

You're referring to fission thermals, from nuclear power stations, I
take it, as distinct from the more usual thermonuclear-powered
thermals...