So for a steady state flight, climbing, decending or S and L the potential energy converstions are going to be constant
Sorry MJ, I don't think that's right... For a steady descent, gravitational potential energy is being lost. That's why the equation which Send Clowns gave works:
drag = thrust + W sin (angle of descent)
That's also why it's possible to have a steady descent with no power.
FFF
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