Page 4 of 15
Re: High Speed Two
Posted: 14 Sep 2009 13:47
by Dave
Even at 300mph it'd still take ten hours! On the hop driver changes then!?
Or can we build a huge undersea citadel-service station with horrendously priced snacks and a Macdonalds?
Re: High Speed Two
Posted: 14 Sep 2009 14:12
by Kevo00
Ten hours, not too bad - would be competitive with air!
Re: High Speed Two
Posted: 14 Sep 2009 14:54
by orudge
Dave Worley wrote:Even at 300mph it'd still take ten hours! On the hop driver changes then!?
Pilots seem to manage it.

No doubt on some sort of a long, straight route as this, there could be some sort of an "autopilot" system, no?
Re: High Speed Two
Posted: 14 Sep 2009 16:31
by railwayman
Ideas for the tunnel:
1.Maybe we can put rocketboosters at the end of the train (Scramjet - about 15000 kph)
2.Use maglev (as in the proposed project) to go on 50'000 kph.
3.Steal all the planes, sell them in the black market and pretend we dont know anything about it.

Re: High Speed Two
Posted: 14 Sep 2009 17:02
by Born Acorn
Make the tunnel a vacuum, or at least replace the normal air with helium. Should remove enough air resistance to enable much faster speeds than conventional maglevs.
Re: High Speed Two
Posted: 14 Sep 2009 17:09
by railwayman
Born Acorn wrote:Make the tunnel a vacuum, or at least replace the normal air with helium. Should remove enough air resistance to enable much faster speeds than conventional maglevs.
The vacum is a part of the maglev plan.
PS. If youre wondering:"What is that maglev he is talking about"
I read it in one magazine (about 1 or 2 years ago)
Re: High Speed Two
Posted: 14 Sep 2009 17:12
by Dave
Re: High Speed Two
Posted: 14 Sep 2009 18:44
by yoyo1505
I watched a documentary on YouTube about the vactrain the other day and it was really well done and thought out. Only problem is they calculated it'd cost $10 Trillion, use the entire world's steel production for a year, and even if we started now (I think technology needs to get a bit further), it probably wouldn't be ready until the turn of the century! But the design concept was sound at least.
Re: High Speed Two
Posted: 15 Sep 2009 07:43
by teccuk
yoyo1505 wrote:I watched a documentary on YouTube about the vactrain the other day and it was really well done and thought out. Only problem is they calculated it'd cost $10 Trillion, use the entire world's steel production for a year, and even if we started now (I think technology needs to get a bit further), it probably wouldn't be ready until the turn of the century! But the design concept was sound at least.
Brilliant!
I demand we set up a tt-forum pressure group to lobby government to build this wonderful device!
Best thread ever.
Re: High Speed Two
Posted: 15 Sep 2009 16:31
by railwayman
Why cant they build a gigant, vacum glass "tube" on the water with tunnels or bridges so ships can get trough.

- untitled.PNG (12.01 KiB) Viewed 1257 times
Re: High Speed Two
Posted: 15 Sep 2009 16:35
by lawton27
having it under-water is simply easier, as the trains run in the tube as its faster because its a
vacuum (no air resistance) so they can go faster.

Re: High Speed Two
Posted: 15 Sep 2009 16:42
by railwayman
railwayman wrote:Why cant they build a gigant, vacum glass "tube" on the water with tunnels or bridges so ships can get trough.
extra costs for the concrete to build it underwater
Re: High Speed Two
Posted: 15 Sep 2009 16:50
by JGR
You underestimate how big waves and weather are on the open ocean, and also how big ships are (both above and below the water).
Bridges will easily end up having to be over 100m high and a half-mile long just for sea traffic, and how can you anchor them? The sea is too deep.
Plus waves of around 30m in storms would make mincemeat of of any surface tube.
Arguably you could use floating support struts with some kind of pre-emptive, active, real-time length correction, but the cost and technical issues of that would essentially approach infinity.
I wouldn't want to be on a train on such a structure either...
It'd be cheaper to build an enormous boat that goes at 300mph powered by a nuclear fusion reactor.
As for your vacuum point, glass isn't that strong, and would have to be very thick to hold a vacuum like that.It's also brittle and would break very easily. Bad combination.
You'd probably have to make it out of concrete or metal. But then it'd sink, so you might as well just put it on or under the ocean floor, which is where we started from. Then there are things like ocean trenchs, underwater features, subduction/creation zones, etc.
I'd say just resurrect Concorde instead...
Re: High Speed Two
Posted: 15 Sep 2009 16:57
by railwayman
Ok. Plan No2. Build it underwater (bottom of the ocean) with a semi-fast service calling at atlantida (i dont know in english. pergaps Atlantia).
Plan No2.2 For less costs:
Build the maglev waterproof an dont build the tunnel
Plan No2.3 Same but instead of no tunnel it could be a forcefield but were talking a bit too much in the future.
PS. The thread is about HS2 so i will stop talking about this tunnel.
Re: High Speed Two
Posted: 15 Sep 2009 17:39
by lawton27
JGR wrote:
I'd say just resurrect Concorde instead...
The French wont allow that...
Too dangerous (their opinion not mine)
Re: High Speed Two
Posted: 15 Sep 2009 19:39
by Kevo00
railwayman wrote:
PS. The thread is about HS2 so i will stop talking about this tunnel.
Lets be fair, HS2 probably has as much chance of actually being built as a vacuum maglev tunnel. So why not?
Re: High Speed Two
Posted: 15 Sep 2009 19:40
by yoyo1505
If you have 50 minutes I suggest you watch the fascinating documentary I mentioned earlier:
http://www.youtube.com/watch?v=frYWTrEfPRs
Re: High Speed Two
Posted: 16 Sep 2009 14:11
by railwayman
Just one thing bothering me. If the tunnel is based on the concept that air would keep it at the altitude then wouldnt it sink if it will be vacum?
Re: High Speed Two
Posted: 16 Sep 2009 14:21
by Rubidium
railwayman wrote:Just one thing bothering me. If the tunnel is based on the concept that air would keep it at the altitude then wouldnt it sink if it will be vacum?
No, physics dictates that air is heavier than a vacuum. As a result if the vacuum would be lost and air would rush in the tunnel will sink a bit.
Re: High Speed Two
Posted: 16 Sep 2009 14:22
by railwayman
Thanks!