Space Elevator defeats the Rocket Equation!

To accomplish our robust future of moving off-planet, Space Elevators are necessary, compatible, and complementary to rocket architectures. The future needs both communities to work together. It seems obvious that cargo should be moved by a permanent infrastructure while people should be moved rapidly.  This flows naturally once one understands the strengths of space elevators. Wikipedia defines the rocket equation as: The mathematical equation that describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself using thrust by expelling part of its mass with high velocity can thereby move due to the conservation of momentum.

Comparisons of rocket equation results show that delivery to LEO is roughly 4% of the mass on the pad and delivery to GEO (or trans-lunar insertion) is about 2%.  In comparison, delivery to GEO or Apex Anchor by Space Elevator is 100% of payload at the Earth Port.   There are a few items that need to be recognized when looking at the rocket equation:  there are no cost nor reusability factors inside the rocket equation.  As a result, the rocket community can decrease the cost and leverage reusability of rocket stages to increase operational efficiency. However, those actions do not improve the performance of the rocket equation. The Tsiolkovsky rocket equation of 1903 still responds only to gravity. The Earth's gravity numbers are draconian and have a considerable impact on efficiency at liftoff and flight.  Another comparison would be with reference to the Moon. The Saturn 5 deposited 0.5% of pad mass onto the surface of the Moon and returned 0.18% to the ocean upon completion of the mission.  Those are tough numbers to build our future around. However, if you raise 20 MT to GEO and the Apex Anchor with electricity, you have beaten gravity and added tremendous velocity (7.76 km/sec) for release towards mission destinations. Yes, the Space Elevator defeats the Rocket Equation. 

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