Hi John,

You are correct. The physics equations show that you will get the same
height regardless of the weight of the glider.

However, I think it is true that a heavier glider will have a slightly
higher pull-up. I don't think the difference is very much though. Both
gliders will have similar frictional losses and losses due to inefficiencies
during the pull-up.

Paul Remde

"John Rivers" wrote in message
...
I was trying to work out the expected height gain from a pull up
Experienced glider pilots say you will get a better pull up with a
heavier glider / water etc.
But I can't see this from my (probably incomplete) equations:

total energy = potential energy + kinetic energy

total energy before pull up = total energy after pull up

m * g * h0 + m * pow(v0, 2) * 0.5 == m * g * h1 + m * pow(v1, 2) * 0.5

with h0 v0 being height and speed before pull up
and h1 v1 being height and speed after pull up

mass cancels out of this equation

I think I need to include momentum in there somehow?