The 4 forces affecting an airplane in level flight are gravity, lift, thrust, and drag. By
altering one, the others are affected. My question is could a wing (retractable) be installed on top of a vehicle with a computer controlling the configuration of the wing to 
maintain a constant lift of 50% when speed allows. Reduction in weight results in reduction in thrust. How does the increase in drag on the wing compare with the pros of lift regarding fuel burn.