I wrote:
Second, the cables would not move much faster than the fastest
cables used in excavation equipment, elevators, cable cars, ski
lifts and the like. People have been using cables for a long time.
If they could make them move much faster, I expect they would.
I believe elevators are the fastest moving cable driven equipment.
Hitachi has developed monster high-speed elevators that will travel
at 480 m per minute (28 kph). They are driven by 240 kW motors. See:
www.hitachi.com/ICSFiles/afieldfile/2007/08/07/r2007_technology_lf.pdf
My guess is that we have reached the limits of cable driven elevators
and models faster & bigger than this will have to be electromagnetic,
like vertical maglev trains.
- Jed
