Lets say Mt. Everest was located on the equator. How much more efficient would it be to launch a rocket from the top of this mountain as compaired to a sea-level Florida launch? There would be much less atmosperic drag since you would be starting out 5-miles high. You would be slightly closer to space. The "sling-shot effect" would aid the launch. The rocket motor nozzle could be slightly wider (at higher altitude, wider is better). I am curious to know how much this would help (slightly heavier payload). Would it be 5% more efficient?