[throwaway99OO]

I have a bit of background on rotor systems. That TsF-18 is puny compared to other rotational systems. See below.

Largest Centrifuge: Regarding the largest centrifuge in the world, perhaps the TsF-18 in Russia has a large diameter but the JET Tokamak [1] flywheel spun a 775 TON rotor at a speed nearly 6 times what is cited for the TsF-18. The Tokamak's centrifuge's provided over 3.8 gigajoules of energy. To provide a more intuitive sense of that energy, 3GJ is equivalent to a 100kg mass traveling at 7.7km/s [2].

Fast Flywheels: OakRidge National Laboratory [3] achieved over a 1.4 km/s tip speed and that was back in 1985.

Large Vacuum Chambers: The Large Hadron Collider[4] is a vacuum system over 5 miles in diameter although toroidal in nature.

1: https://www.euro-fusion.org/fusion/jet-tech/jets-flywheels/ 2: https://www.calculatorsoup.com/calculators/physics/kinetic.p... 3: http://www.guinnessworldrecords.com/world-records/fastest-ro... 4: https://en.wikipedia.org/wiki/Large_Hadron_Collider

[nathannecro]

First off: thanks for the reply. Secondly, how could I forget about the LHC...doh!

So it does seem like it is possible to get a spacecraft spinning up to speed. It'll just require a lot of effort and even more capital.