"
http://www.tux.org/~milgram/papers/alds_auvsi2003.pdf

This paper was referred to me by an aerodynamics
professional/glider pilot. I hope he won't mind if I post
this limited excerpt from his email to me:

"I notice you carrying the torch for good physics on r.a.s.,
more power to you. But don't fret over it (especially not on
r.a.s.), since as you've noted you have to look at the
energy losses to see any difference, and no analysis can
answer this without incorporating some kind of trajectory
analysis. That would have to include some kind of
representation of the glider's long-period longitudinal
dynamics (a.k.a. phugoid dynamics), and a way to optimize
the pullup for each given weight. Plus you have to decide
what the rules are (pullup from same airspeed, pullup from
weight-appropriate MacCready speed, etc.).

Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

We can appreciate that very intelligent view on the question. In no ways, it
denies the fact that in our system, no energy is created, so ultimaly we
will have to balance the conservation of energy theorem. This is simple:
kinetic energy, potential energy and drag. Not matter what trajectory you
will choose, you will have to balance the equations even if you use phugoid
dynamics. There are no rule here for trajectory, just go for max height!!!
We did the maths, and we look at our total energy probe (i.e vario), we
notice we're trashing energy in a pull-up (if the probe is well calibrated),
otherwise in still air, nothing is gained.
This is going way further than I expected!!! We had all kinds of comments,
this one from a mathematician CFI who conclude that ballasted will go twice
as high, another from an outsider power pilot who candidly state that he
noticed that pull-ups with a load (passengers) were more demanding (we all
know that power pilots are no physicians ;-)... and that soaring is an art
that defy laws of physics) and all kind of rewritten equations that give
a substantial advantage to the ballasted. Don,t get me wrong, we are talking
one hundred feet difference on an avergage 300'+ pull-up!!!!! Now, that is a
lot of drag!!!!
We sill expect a probant mathematical proof, or a reality check in still
air.
BQ