Electromagnetic Space Launch

The G-Force Wikipedia page says that humans can survive 20G horizontally “eyes in” for up to 10 seconds and 10G for 1 minute.

An accelerator of 14G for 10 seconds (well below the level that’s unsafe) gives a speed of mach 4 and an acceleration distance of just under 7km. Launching a 100 metric ton spacecraft in that way would require 14MW at the end of the launch path plus some extra for the weight of the part that contains magnets which would be retrieved by parachute. 14MW is a small fraction of the power used by a train or tram network and brown-outs of the transit network is something that they deal with so such a launch could be powered by diverting power from a transit network. The Rocky Mountains in the US peak at 4.4KM above sea level, so a magnetic launch that starts 2.6KM below sea level and extends the height of the Rocky Mountains would do.

A speed of mach 4 vertically would get a height of 96Km if we disregard drag, that’s almost 1/4 of the orbital altitude of the ISS. This seems like a more practical way to launch humans into space than a space elevator.

The Mass Driver page on Wikipedia documents some of the past research on launching satellites that way, with shorter launch hardware and significantly higher G forces.

2 comments to Electromagnetic Space Launch

  • Jamil Djadala

    You are missing that these 100 metric tons must be accelerated to earth escape velocity(11 km/s, otherwise object will fail back to earth), so there are additional required energy of 1680 MW/hour.


  • I didn’t miss it, I noted that it was 1/4 the height of the ISS. It’s a significant portion of the energy needed – effectively the first stage of a multi-stage rocket.

    The same amount of energy would launch 25 tons of non-animal stuff to the height of the ISS.