Scott
Please accept my apology for shouting
Of course everyone knows that a glider cimbing in a thermal is gaining
potential energy.
Evryone knows that a ballasted glider will will trade potential energy to
kinetic energy at a faster rate than a dry glider.
No matter how we look at it, we will have to repect the law of conversation
of energy.
My problem was set in still air, maybe i should have made this clear. So,
you have to balance the total energy at the start of the climb with the
total energy at the end of the climg. I am going to be rude again, THERE IS
NO WAY AROUND THAT. That is what I meant with the big letters.
I solved the equation without taking drag into account, my feeling is that
it has little effect ( both glider will be affected by drag, but we will
need to cut down H a bit).
Going down towards the center of the earth ballasted is one thing, going
away from it is another ball game.
You will need the extra enrgy to lift the extra weight and it will be traded
from the extra kinetic enrrgy you had at the start.
For simplcity, if you set start point at H=0, all you have a start is
kinetic energy and there is much more stored in the heavy glider. Then you
solve for potential energy at the end, knowing your final speed, and you
find height achieved.
Then there is drag.....
Then there are conflicting reports from pilots who don't care about maths,
but have the right stuff....
This is fun, isn't it.:-))))
Réjean
"Scott Correa" a écrit dans le message de
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Shouting is unbecoming a gentleman..................
Somehow I don't think you understood what I said.
Every test I have seen published shows the max L/D
point moving to the right (ie occuring at a higher speed)
with an increase in wing loading. The sink rate curves
do the same thing. So again I ask, doesn't the heavier
airplane bleed energy more slowly..................
This has nothing to do with starting the engine......
Oh Yeah I also forgot to mention that although you cannot
create energy, you can add it to the glider by flying in air
going up faster than you are sinking thru it.........................
Last time I looked at total energy systems, it read airspeed
(kinetic energy) and barometric pressure (potential energy)
Scott
"szd41a" wrote in message
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YOU CANNOT CREATE ENERGY UNLESS YOU FIRE YOUR ENGINE!!!!!!!
"Scott Correa" a écrit dans le message de
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Mark.
What about the L/D polar being skewed to the right to the benefit of
the
higher
wing loaded vehicle. At VNE the heavier a/p is cleaner and will glide
farther.
If both a/p's pull up together, the cleaner a/p runs out of energy
last.
It
looks to me like
heavier climbs further.....
Scott
"M B" wrote in message
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Since mass is a constant factor on both sides of the equation, it
cancels out. Therefore there should theoretically be negligible
difference
in the pullup altitude gained between the ballasted and unballasted
cases.True except for two things:The ballasted glider has more induced
dragwhile at the same airspeed as the unballasted oneThe ballasted
glider
also has a higher stall speedSo the unballasted glider will go
higherMark
Boyd
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