1. ETT's might be dangerous, but they are neat
looking sci-fi.
2. Aren't hyperspeed trains also a big danger in
terms of sabotage etc - as you have to secure
their tracks too? Things like the TGV etc? 3. On a vacuum moon or something,
the risk of penetration that is posed by external atmospheric pressure goes
away. 4. It has traditionally been far more efficient to move mass by rail
than by truck or plane (by a
long shot) - and this method looks even more
energy efficient. If your concern isn't the danger to the apparatus, but the
cost efficiency of the system, this system may move KGs (and conventional rail
definitely does) far cheaper
across continental distances than your air-net.
I'm not saying this is viable any more than a space elevator is (both are
contestible points). But both also make for some interesting chrome for a
setting (beanstalk anchor would be an interesting target point for a DS2 or
SG2
mission..... and so would a tube-train line.
Thomas Barclay schrieb:
> 3. On a vacuum moon or something, the risk of
Right. But then you don't need to build a tunnel to reduce air resistance. As
far as I can see, reducing air resistance is the main advantage of the
proposed tunnel scheme.
> 4. It has traditionally been far more efficient to
You didn't mention two factors:
* the speed of the transport. Basically, you can move stuff cheaply and
slowly or fast and expensively. Conventional rail is very slow - slower
than trucks over almost any distance. Depending on your specific goods and the
costs of delays in delivery, it can be more profitable to move stuff by air.
* the cost of investment, which has to be offset by the income from the
transports. If the tunneling is so expensive that 90% of the transport price
goes for servicing the debt from the original investment, it won't help if
actually operating the train costs next to nothing.
A specific example of this is the Transrapid Maglev train project in Germany.
Nifty technology, but the cost of building the track was such that it could
not be operated profitably even under very optimistic assumptions.
> I'm not saying this is viable any more than a
Definitely :-)
Greetings Karl Heinz
> At 2:58 PM +0100 11/6/02, KH.Ranitzsch@t-online.de wrote:
I don't know. I should suspect that when your loads get really really large,
you've got lower cost for transporting large heavy loads long distances. Take
a movement of military vehicles from Fort Hood Texas to a port in Savannah.
The military is far more likely to move everything by rail than by truck.
Fewer people have to be operational at one time (one or two train crews vs a
company or more of transportation drivers, repair trucks for flats, etc).
I'll bet that for large loads, your costs and efficiency go up when you're
moving large loads over long distances. Otherwise, why would
inter-modal (container) transportation in the US rely so much on rail
for the long distance movement across the country?
> TomB wrote:
> 2. Aren't hyperspeed trains also a big danger in
Sure, they are. But they only move at two-three *hundred* mph, whereas
the
long-distance ETT capsules are supposed to move at four *thousand*
mph...
from a kinetic-energy point of view that's a rather significant
difference.
From a braking-distance point of view too, at least if you assume the
same emergency deceleration for both vehicles (limited more by what the
passengers/cargo can endure than by what the vehicle itself can survive)
:-/
> 4. It has traditionally been far more efficient to move mass by rail
In addition to KHR's comments, you forgot one very important factor: rail is
"far more" efficient *iff* it goes *all the way to the final destination*. If
you need to use a truck even a short way of the distance (ie., to and from the
railway terminals), the efficiency of the combined
rail-truck system drops very fast - which is one of the major reasons
why
long-distance trucking is common even on routes where there's a railway
line available. In spite of the gains from container systems, the transfers
from truck to train and from train to truck often cost you more than you
gain by using railway for the vast majority of the distance :-(
Side note to Ryan: Transporting tanks by train from Fort Hood to Savannah
harbour is a good example of this: the railway tracks do stretch all the
way from Fort Hood itself to the quays in Savannah, so it is easier to use
them than to use the tank transporters. If the tanks need to move any real
distance away from the railway line, you immediately need those transporters
again (or you need to replace the pavement of every road you drive the tanks
on <g>)... which means that you need to get those transporters and their
drivers to whereever it is they are to pick the tanks up...
> If your concern isn't the danger to the apparatus, but the cost
Conventional rail *today* is far cheaper than the air net mainly because
the railways were built half a century or more ago. For the most part, the
investment has already been paid off.
However, if you compare the cost efficiency of a *new* long-distance
railway line to that of using aircraft (and building a new landing strip at
either end of the route) it'll take quite a long time before the railway
beats the aircraft, simply because the initial investment is so much larger
for the railway than for the two airports.
(This is a cause of much teeth-gnashing amongst the local Greenies, BTW
-
they love trains and hate all other modes of transport, and can't understand
why the railways (particularly the new ones!) don't show a profit in spite of
being heavily subsidised whereas truck and air transport companies do fairly
well... The distances involved here is the entire length of Sweden, which IIRC
corresponds roughly to the distance
Vancouver-Los Angeles. Not quite "continental" distances, but fairly
respectable nonetheless.)
> I'm not saying this is viable any more than a space elevator is (both
I'd actually rate the beanstalk as more viable than the ETT :-/ Much
easier
to guard (>99.9% of the approaches to it are through open air/space,
which is quite easy to keep under surveillance compared to a extensive network
on the ground), and a much less complex technical system too <g>
Later,
> At 02:58 PM 11/6/02 +0100, Karl Heinz wrote:
Which is why the first operational (well, maybe -- slated for sometime
2003) track is being built in China -- they don't care about costs, it's
a big propaganda piece to say that China is becoming more technologically
advanced.
Of course, if it works as advertised (covering the distance from Pudong
airport in Shanghai to somewhere in the downtown area in around 8-10
minutes) it will be a vast improvement over the 40-50 minute drive, or
longer, it takes these days....
The other reason I've heard for the track going up in China is that they
don't have all the sticky environmental and human health-related
regulations to go through, unlike most/all European and American
countries. Makes me feel *so* much better about the possibility of riding on
it, but I haven't tried to find out if that rumor is really true or not.