[TML] Space Traffic Control (was Re: War rules)

[shadow at shadowgard.com]

On 2 Jun 2008 at 9:35, Knapp wrote:

> On Mon, Jun 2, 2008 at 2:45 AM, <shadow at shadowgard.com> wrote:
> 
> > On 1 Jun 2008 at 18:58, Knapp wrote:
> >
> > > I was reading all that bit about what would happen to a ship if it
> > > hit some poor planet. I started thinking about what would happen to
> > > the planet if some great ship hit it, or even some little cargo ship
> > > that was loaded and had a long vector.
> >
> >
> > Rough rule of thumb. At 3 km/sec, a ship will impact with an energy
> > of roughly the same mass of TNT. This goes up linearly with mass (ie
> > ten times the mass is ten times the boom) and goes up as the *square*
> > of the velocity (ie at ten times the velocity you get 100 times the
> > boom).
> >
> > So at 300 km/sec, a 100 ton *mass* (not 100 dT!) ship will impact
> > with roughly one megaton of blast.
> >
> > That's bad news near the impact point but not so nad even a dozen
> > miles away (the fallout won't be radioactive unless the ship was
> > carrying nukes).
> 
> 
> You will have dust too and that can go from no problem to a long night or
> climate change. This is a good example of a Legal vector VS one that is just
> stupid.

It takes a *lot* to throw significant amounts of dust into the air. 
If there's air. :-)

> Really big war ships doing really high speeds can risk the whole
> planet. I was also thinking about what would happen if, say two cargo ships
> hit. The huge type with 100,000 cargo containers each. Now you have 200,000
> cargo containers raining down on the planet. Obliviously a worst case
> scenario. Perhaps cargo containers could have safety parachutes or
> something. Even on Earth they are a large problem for boaters.

Parachutes won't do a damn thing unless they are moving so slowly 
that they aren't a hazard anyway.

Besides. getting ships to collide in space is *hard*. And if they do, 
unless they have nearly the same vector, the pieces will be small 
enough to burn up.

> > But planets are big. And unless it's got an insane population density
> > the odds of hitting anywhere important are low.
> 
> A nice big wave could do a lot of damage to coastal areas.

Raising a significant wave takes a *lot* of energy. Many, many 
megatons, probably even gigatons.

> Living in the USA I could see thinking this way but living in
> Germany, I can't think of any place that it would be OK to have a
> large, fast war ship fall. 

Well, as I recall back in the Cold War days, someone *did* describe 
Germany as having towns about one megaton apart... :-)

Seriously, yes, you'll want to avoid ships hitting the planet. But 
even if they do, the damage in peacetime is apt to be strictly local. 
Hurricanes will do more damage. So will earthquakes.

But the simple fact is that Germany and other densely populated areas 
cover a small *fraction* of the globe.

Heck, you'd probably do far more damage if something hit in the 
"Boston-Washington corridor" (a strip of the East coast that is 
pretty much solid urban area for several hundred miles).

>>> So if I lived on that planet I would have rules about what
>>> vectors were OK, they would have to be vectors that, if the ship
>>> failed, would give people at least 3 weeks go find aid or maybe
>>> less if aid was always in system. This goes double for war ships
>>> and war. Say you are fight for or even against a plant, loose
>>> ship control and then clash into the major city or really harm
>>> the planet. What good is the fight then? Seems to be that it
>>> would be a war crime to take such a vector in the first place.  

Added note. No reasonable or even *unreasonable* ship impact is going 
to "harm the planet". It may cause a lot of damage even cause some 
long term problems with the ecosystem, but the planet is not going to 
be appreciably damaged.

> > The three weeks bit is totally silly as with normal Traveller drives,
> > you can leave the star system in 3 weeks.
> >
> > In 3 weeks at one g you can travel almost 110 AU (without doing
> > turnover). And you'll be travelling at 6% of c!!!
> 
> You miss the point of 3 weeks. This is with the thinking that there is
> nothing in system that can stop the disaster. Perhaps they were all shot
> down or whatever. So that mean you must jump out of system, get help, return
> and fix or tug the ship out of danger. It is the outside number.
> Obliviously, if we are talking a tanker at a big spaceport that needs help
> they will get in in hours if not minutes.

Sorry, but again you are asking the *impossible*. I'm pointing out 
that there's absolutely no way that such a 3 week rules is practical. 
It's probably not even *possible*.

Any ship that's close enough to the planet to be defending it against 
ships attacking after jumping in at the 100 diameter limit *cannot* 
have a vector that might intercept the planet *and* won't won't do so 
in less than 3 weeks.

You have to keep in mind that at typical Traveller velocities the 
ships *aren't* going to get pulled into the planet unless their 
course is already pointing almost directly at it. They are *far* 
above escape velocity.

And saying that the defenders can't use vectors that might intercept 
the planet means that they are crippled in both defense and offense. 

Nobody will abide by rules that will make them lose. Esecially if the 
other side may start orbital bombardment to force the planet to 
surrender once they've gained control of the space around it.

Consider the fact that various military targets (not military 
*installations*, but legitimate military targets) are *still* close 
enough to major population centers to cause major civilian casualties 
if there was a nuclear attack. And this is after 50+ years.

Heck, many of them started out *away* from cities and the cities 
expanded towards them.



--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com