[ifinnegan]

Wish we’d built mag lev trains here.

[Flatus I. Maximus]

Yep, it's a cool idea. Which is why Heinlein used it almost 65 years ago.

[Vince Ferrer]

SpaceX's BFR will be much more economical than current rockets, so much so that any other radical idea would not be able to get funding. this was already the fate of one promising project that I know of.

BFR

[Pontiac]

First off, to propel spacecraft to necessary speeds, a massive amount of power will need to be stored and discharged over roughly thirty seconds, think between 50 and 100 gigawatts! That's equivalent to the power output of around 50,000 commercial wind turbines.

Or 50 to 100 full size nuclear power plants.

That is a lot of power.

And I can’t imagine the size of the capacitor banks that it would need to store that power for quick release at “around 200 million amperes!”

I can’t imagine the noise that it would make when those capacitors were discharged

[867V309]

an 81 MILE vacuum tube filled with track, magnets and superconducting electrical cables, powered by dozens of nuclear plants (!)

but wait! it's built on the side of a mountain!

[sauropod]

bkmk

[E. Pluribus Unum]

Dick Tracy did it first.

[Wuli]

“A generation-1 StarTram design intended to launch cargo vessels will feature a 81-mile tube built up the side of a mountain to reach a launch altitude of 12,0000 to 20,000 feet. The Andes Mountains of Chile or the White Sands Missile Range of southern New Mexico might be ideal locations.”

An 81 mile underground tube = financially impractical.

Cost, cost, cost is ALWAYS a consideration and cannot be dismissed just because the idea sounds “neat”. Witness the Concorde supersonic airliner. Cool idea, financially impractical.

[Bloody Sam Roberts]

Craft will exit the lengthy tube at a speed of 8.8 kilometers per second

For a projected 81 mile trip, the trip/launch would take about 20 seconds.

No human could survive that kind of acceleration.

[sparklite2]

The answer to headlines that
pose a question is usually “no.”

[mrsmith]

Read the same about railguns years ago.