Waveguru wrote:
Gravity does not power our gliders. The forward tilt of lift is what moves us forward.

Say what now?!?

You're flying in equilibrium, in unaccelerated straight line flight at a
speed just above the stall. You have a nose high attitude and a line
perpendicular to your wing surface is pointing rearwards. Where is the
"forward tilt of lift"? You'd need a lift distribution shaped like a
flaccid.....err, a slinky that's toppled forward to sustain this
hypothesis.

Your 'forward pointing force', the one that's opposing drag and "replacing
thrust" if you're of the powered persuasion, is the forward component of
weight. So yes, gravity is indeed our "engine".

CJ
B3