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Posted: 06 Jul 2007 20:19
by Bilbo
Killer 11 wrote:
Egofreaky wrote:heheh Railgun to orbital to drop point... that'd be cool.
That would be so uncool if terrorists would hijack it and turn it into a massdriver... seriously do you realise just how much damage it could cause?
Same with intercontinental ballistic missiles ... yet no terrorist have hijacked one. Such dangerous things are well too guarded by army ...

Posted: 06 Jul 2007 20:26
by Bilbo
Egofreaky wrote:The same consortium then proposed a MagLev track from Melbourne to Perth (about 3,400km). It was objected to by our local air carrier (Qantas) and the plan was never heard of again...
Well, most maglevs operating today are quite short (tens of kilometers), so such long track may be quite expensive. Still, at 500km/h the trip will take about 7 hours. With plane (900km/h) the trip is about 4 hours, but you have to get to/from the airport and all that waiting (luggage, boarding, ...) ... maglev will probably give you creater comfort and may be cheaper.

Plus maglev can have easily few stops (like each 500km or so) on route without considerably prolonging travel time, unlike an aircraft ....

And air carrier objecting? Well, such line would decrease its profit, so its no wonder he's objecting, using whatever reason he can make up :)

Posted: 06 Jul 2007 20:50
by RainierWatcher
How about a floating (in the air) Airport? And I know it would be a monster to code, but it would be handy for big cities, just stick it above it.

http://upload.wikimedia.org/wikipedia/e ... aliant.jpg

Posted: 06 Jul 2007 20:56
by Bilbo
nezzybaby wrote:
Bilbo wrote: Hmmm ... so they should have at least decent acceleration to be able to perform somewhat comparatively to ordinary aircrafts ...
I've been trying to do a few calculations on acceleration. The X-43 was launched from a pegasus rocket which achieved mach 3 in about 8 seconds, then the scramjet kicked in and flew for a total of 10 seconds up to a speed of mach 10, assuming it only achieved its top speed at the very end of the flight (i can't confirm this), then the acceleration can be aproximated to 0.5 machs a second, or 600km/h/s. In other words the acceleration is ludicrously fast and should be useful against regular aircraft.
600km/h/s = 166m/s^2

Any passenger on board will experience 16 g.
Quite a lot, though with special seatings, humans can survive that (they can survive 17g's for longer time when "laying on ground", see
http://en.wikipedia.org/wiki/G-force#Ho ... is_g-force )

But still, it won't be very comfortable and not very safe :)
nezzybaby wrote: I realise rocket sleds are incredibly unrealistic, but who knows by 2100 they may be economically viable.
Having to clear land quite far away from the track so nothing won't be ignited doesn't sound too practical. Such speeds are (theoretically) achivable by maglev/vacuum tube maglev, so maybe there will be usable economically viable transportation in 2100 with speeds of today rocket sleds, but it will achive that speed in another way than burning tons of fuel ...

Posted: 06 Jul 2007 20:58
by Bilbo
RainierWatcher wrote:
Killer 11 wrote:
Egofreaky wrote:heheh Railgun to orbital to drop point... that'd be cool.
That would be so uncool if terrorists would hijack it and turn it into a massdriver... seriously do you realise just how much damage it could cause?
It'd be damn difficult to adjust the trajectory, as it would be huge. Plus I think the ideal location was in Antarctica, but it has been ages since I saw the idea. Drop pods though, would be neat.
Nope, ideal is anywhere on equator, as the speed of earth rotation (cca 0.5km/sec) will add to the speed they propel the payload. So to get on orbit, less energy is required (same for classic rockets .... best to launch them from places close to equator)

Posted: 06 Jul 2007 20:59
by Bilbo
RainierWatcher wrote:
Killer 11 wrote: Just make sure you hit an ocean with something big, the cunami would do the rest :roll:
Going further off topic but, you need something really big to make a tsunami. However, I'd consider aiming it at that island near Tenerife that might then fall into the sea, drowning all of the east Coast of america, prompting Bush to declare a "war on nature". :lol:
Big? Like 5km asteroid? :)

Posted: 06 Jul 2007 21:01
by RainierWatcher
Bilbo wrote:Big? Like 5km asteroid? :)
Yes, that would do it easily.

here, try this website:
Impact effects calculator

Posted: 06 Jul 2007 22:00
by Bilbo
RainierWatcher wrote:How about a floating (in the air) Airport? And I know it would be a monster to code, but it would be handy for big cities, just stick it above it.

http://upload.wikimedia.org/wikipedia/e ... aliant.jpg
This will pose multiple problems:

What if whatever is keeping arport in the air breaks down? City would be crushed

How to transport people to the airport above them? By planes from, ehm ... same airport in the ground? This may be the most major problem :)

Posted: 07 Jul 2007 00:19
by ostlandr
You don't even need a lot of mass. In vacuum, a superconducting solenoid coil can fire ball bearings at hypervelocity. Those will kill about anything. Now, if someone put a bunch of heavy electromagnets into a sattelite with, say, really precise pointing gyros, advanced imaging and a good solar power supply. . . **cough Hubble cough **

For orbital bombardment of earth, you'd need to launch rocks with enough size to make it through the atmosphere without burning up. The mass would be a problem. Need a lot of delta-vee to get them to orbit in the first place.

Killer 11 wrote:
Egofreaky wrote:heheh Railgun to orbital to drop point... that'd be cool.
That would be so uncool if terrorists would hijack it and turn it into a massdriver... seriously do you realise just how much damage it could cause?

Posted: 07 Jul 2007 01:01
by Bilbo
You can "replace" large mass with even larger velocity for the devastating effect. One tiny piece of candy (1 gram) travelling at 99% speed of light have same kinetic energy as 10000 ton asteroid at 10km/sec
ostlandr wrote:You don't even need a lot of mass. In vacuum, a superconducting solenoid coil can fire ball bearings at hypervelocity. Those will kill about anything. Now, if someone put a bunch of heavy electromagnets into a sattelite with, say, really precise pointing gyros, advanced imaging and a good solar power supply. . . **cough Hubble cough **
Sun have power only about 1.4KW/m^2. You will need to accumulate energy from large solar panels for long time to shoot anything at "hypervelocity"
Another problem will be action and reaction. Every shot will slightly change the orbit. Shoot enough against your orbiting direction and you will slow down the satellite and burn it in atmosphere not much later
ostlandr wrote: For orbital bombardment of earth, you'd need to launch rocks with enough size to make it through the atmosphere without burning up. The mass would be a problem. Need a lot of delta-vee to get them to orbit in the first place.
Once they are at orbit, you can make slight bump to them to slow them down (like decelerating them 50m/sec) and if they are at low orbit, this will case them to drop to ground few thousand kilometers away ...

Of course you need good calculations for that to figure exact place of impact.
Killer 11 wrote:
Egofreaky wrote:heheh Railgun to orbital to drop point... that'd be cool.
That would be so uncool if terrorists would hijack it and turn it into a massdriver... seriously do you realise just how much damage it could cause?
Edit: fixed quoting

Posted: 07 Jul 2007 20:41
by athanasios
Hey boys, isn't this discussion led astray? This is not a physics forum :lol:
Concentrate on what to draw for a SF climate or for year >2050, or we will be discussing for 'void'.

Posted: 09 Jul 2007 00:32
by RMJ
Its just gotta have to suck to have the train break down in a vacuum tube and one of the windows break xD then you eyes are gonna get sucked out xD now thats major Draaag =)

Posted: 09 Jul 2007 07:45
by Zephyris
It would be a simple graphics conversion to introduce maglev and vacuum maglev in a sci-fi climate - rail ---> maglev, electrified rail ---> vacuum maglev. Monorail/maglev slots would then be available for really futuristic tech - anti grav???

Posted: 09 Jul 2007 11:44
by Bilbo
Zephyris wrote:It would be a simple graphics conversion to introduce maglev and vacuum maglev in a sci-fi climate - rail ---> maglev, electrified rail ---> vacuum maglev. Monorail/maglev slots would then be available for really futuristic tech - anti grav???
Why not add vacuum maglev as fifth rail type in all classical climates instead? This would allow the inventions to continue past 2050 and "extend" the gameplay.

Posted: 09 Jul 2007 18:04
by nezzybaby
^adding an extra rail set is not an easy task, creating a new train or replacing an existing track is slightly easier.

The most obvious way for me is to simply replace monorail, its the least rellevant of the current track types, i mean when was the last time you got on a monorail outside of a theme park? At least maglevs are used for slightly longer distances and the speeds are realistic. Replacing all 4 sets of tracks completely defeats the object of extending the game play. IF the first rail set is maglev, then the game has to start in 2020 which is pointless.

Posted: 09 Jul 2007 18:47
by Bilbo
nezzybaby wrote:^adding an extra rail set is not an easy task, creating a new train or replacing an existing track is slightly easier.
Maybe, but should be possible, as el. rail was added in addition to classical rail ...

Posted: 10 Jul 2007 01:29
by DaleStan
I believe the major portion of the work on el-rails was redesigning the system so that new rail-types could be simply dropped in, without much additional hassle.

hovercars

Posted: 10 Jul 2007 21:27
by ~shoestring~
perhaps a new road set instead of/as well as yet another rail type? (trying to even things out a little :wink:)

hows about a sort of mag-lev equivalent for road vehicles?
hovercars! :mrgreen:

Re: hovercars

Posted: 10 Jul 2007 23:28
by Bilbo
~shoestring~ wrote:perhaps a new road set instead of/as well as yet another rail type? (trying to even things out a little :wink:)

hows about a sort of mag-lev equivalent for road vehicles?
hovercars! :mrgreen:
Well, but would hovercars need any road at all? :)

Posted: 11 Jul 2007 10:36
by Egofreaky
Well, how would the cars hover?
It would be kind of reasonable to assume they work on a form of magnetic levitation as well, which means that they'd need to have MagLev roads too (and no more off road hehe)
That, or electrified roads for electric engine trucks...

I was also thinking that boats wold probably get an overhaul.
I mean, you guys know about catamarans, right? Two-hulled boats. They're more stable thanks to the second hull, and they move faster as there's less of them in the water. Surely we could start cargo transport on catamarans in the near future...