The Race To Create a Hyperloop Heats Up (wsj.com)

An anonymous reader writes: When Elon Musk unveiled his idea for the "Hyperloop" transportation system based on capsules zipping through depressurized tubes, much was made about the enormous technical challenges the system would face in development. However, that didn't stop a number of companies and organizations from starting to work on it. Several companies are pushing the development work hard, and it's shaping up like a race to a workable prototype. University teams are only increasing their efforts as well. "The Illinois team enters the SpaceX contest with a strong competitive edge. This is its fourth Hyperloop design project, the first dating to fall 2013, and the Hyperloop is now a part of the MechSE curriculum. The team has assembled an interdisciplinary network of faculty from aeronautical engineering, thermal dynamics, mechanical engineering, electronic engineering and software, and two of the team members have interned at SpaceX."

Comments

I wonder if it can aid in space launches.

[SharpFang]

Imagine a section of tube going splitting away from the main network. It has an airlock shortly after the split, then gently curves up a tunnel through a mountain, and exits at a rather steep angle upwards. Then there's a quick-acting airlock at the opening.

A special train is loaded - a rocket adapted to travel through these tubes. It speeds up to the regular Mach 1 in the "civilian" section of the tunnel, then goes down the branch and gains another 2-3 Mach. The airlock at the end opens right before the rocket reaches it, then the hyperloop propulsion module drops on a parachute while the rocket ignites its engines. We've just shaved off first 1.5km/s out of the required 9 or so needed to reach orbit - and with the tyranny of rocket equation, that's quite a bit of savings!

Re:I wonder if it can aid in space launches.

[frnic]

Thew airlock would need to be long enough so that the pressure could be normalized before the outer door is opened, while the rocket is traveling at Mach 3. Probably in the neighborhood of a mile or two if you pressurized the airlock in one second.

Constant/repetitive cycling of the pressure would certainly be very stressful to the structure.

Re:other enormous challenges not considered.

[SharpFang]

What percentage of Americans consider flying with commercial airlines to be the mark of poverty?

Hyperloop isn't a replacement for buses or city cars. It's a replacement for airplanes. Supersonic travel with high initial but low unit cost - airplanes are very wasteful because they need to use a lot of energy just to prevent falling. Hyperloop train, once running, keeps running with only minimal friction losses and can recuperate most of energy used on acceleration during braking.

It actually drives a lot of funds towards science/education. But yeah, the initial investment is huge. I mean, something like, 6% the amount any of the wars USA started!

Re:An even better design?

[SharpFang]

https://en.wikipedia.org/wiki/...

12km, or 40,000ft and they were unable to keep up due to heat melting the drill.

If you're going to cut into Earth curvature, in a straight line with maximum 10km depth the longest you can go is 714km.

Re:.. pressurized to minimize the G forces effects

[Rei]

The author doesn't know what G-forces are, that's all. They were trying to say that the person isn't exposed to a vacuum.