Well......if someone wants to get serious about this concept I would tell them to call Obama. No doubt he'd throw a quick $250M at it....even if it's destined to fail....:D

I think someone already did...

http://upload.wikimedia.org/wikipedi...rack_Obama.jpg

The ADA will insist on making the tube bigger to accomodate the fat people-
then there will be that one fatie that doesn't quite fit and then it will be shut down due to non compliance-

and the fattie gets a check for their inconvience-

Ha!!

Brittle system. Elegant in theory, very little tolerance for malfunction. That is my overall impression.

You Obama haters should confine your posts to PARF.

Ok I did read the whole thing and great Alpha draft. There is still so much to figure out, but I like the open source Idea where can I download alpha 0.1 :D

I don't know if I would say the engineering sound until it's tested, but his people have done their homework. Still WAY more to do on the safety and recover side, and I am still thinking not everything environmental (external to the tube) has been taken into affect, but hopefully some retired NASA engineers and other people that have actually accomplished things will add to the effort and make it viable.

I would recommend he go to a smaller trial system strictly for cargo to start, then take the lessons learned from it, the UPS or Fedex tube for example.

At least someone is thinking outside to normal parameters...

A little research into the "air bearings" which really should be called air casters.

Air Caster Floor Specifications and Floor Requirements for SOLVING Air Bearing material handling equipment. Floors for Air Casters

For these to work properly, the inside of the tube, after welding, will need to be honed. 2% of the diameter of the bearing. Since the bearing is 3.5' x 4', the effective diameter is A=pi(d^2)/4 or d=sqrt(A*4/pi) = 4.22. Honing will need to be to 0.085" on an 88" tube. That is pretty darn close tolerance. This is +/- 0.1%. Metering tubes for measuring flow accurately are +/-0.25% for just the first pipe diameter.

An alternative to metal honing would be coating the inside with an epoxy compound and then honing that. Again, extreme tolerance are required to make the air caster work.

http://www2.emersonprocess.com/siteadmincenter/PM%20Daniel%20Documents/Meter-Tubes-DS.pdf



0.005" inches.

No one hates Obama, but we all know he is incompetent to hold that office. He should be in Hollywood co-hosting a morning show with Kelly Ripa. We'll wish him well when gets there.

the entire inside of the tube, after welding, will need to be honed??

Doug, go to PARF. Good bye.

The energy cost to heat all the water, run a big enough suck machine and other control functions for this 'tube" will be staggering......where are the cost savings ?

You'll have to have expansion joints at, say, every pylon...

What happens when an air bearing encounters a spot that is not to those specs? Let's say a small dent or ripple in the tube, a weld that wasn't completely ground down or that cracks, or the deformed hole left by a rifle bullet? Does it make a difference that the bearing is traveling at 800 mph?

I'm imagining a situation where the 800 mph bearing hits a local deformation in the tube, and rips the tube like a fish being gutted.

I say we just build a giant air hockey table and load people up onto pucks that will bounce between LA and SF.

Not surprisingly, other people/companies have introduced improvements on the idea. This one addresses some of the tube & welding issues:

Autodesk's Idea to Knit the Hyperloop Out of Carbon Fiber - Businessweek

Six Flags might want this!

I think that the producer of this vid read this thread. ...and added a few items.

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Hyperloop's biggest problem is that it is lead by a charlatan who consistently overpromises and underdelivers.

Elon musk's greatest talent is showing us how to spend our money.
If he wants to use HIS money (only), then I will support his hyper-loop ideas completely.

If he is once again trying to tell us how HE should spend our money, then he can go pack sand.