Richard sez:
}Scott Kellog:
(Ahem, Richard? Why do you think my signature is 2G Kellogg? Come on, you
see my name on your cereal box EVERY morning! :-)
(Wakes)
> [describes big wave off bow (or stern) of a ship]
> Now, as you may notice, the water behind a ship, inside the barriers of
> the wake, is much less turbulent than either the wake itself or the water
> around it.
}Wellllll, actually there is a difference between this wave & a shock
}wave generated by an aircraft. The angle between the wave fronts in water
}will *always* be 48 degrees. No matter how fast the boat moves. Watch
}sometime. The angle between the wave fronts for a plane in the air
}changes. It gets smaller (the wave fronts move together) as the plane
}flies faster.
All quite true. However, I needed something visible to illustrate a
shockwave that we all are more familiar with.
}I think the reason this happens on the water is surface tension. A
}classic example of second order effects have a major impact on first
}order effects.
I seem to remember someone once saying that the angle of a wake has to do
with the gravitational force on the water, density, as well as surface
tension. Thus on another planet, all ships would have the same angle to
their wakes, though it may not be the same as it would be for a vessel on
earth.
(Transonic Drag)
}The human body is not terribly stable in air,
}and @ around .7M & up we should start to see the results of
}compression of the airflow around parts of the body. That is, for
}instance the shoulder will produce more lift than the foot, for a
}while, etc.
}Me, Id' hate to experience the transonic region, with sock wave,
}compressed flow, turbulence, & induced flutter, without the aid
}of some titanium betweem me & the air. :=)
The Buffetting experienced by aircraft in the transonic region is
mainly caused by the shockwave passing over the control surfaces of
The aircraft. This is acutally why the engineers used to call it
'The Sound Barrier' The aircraft of the time were designed in such
a way that the sonic shockwave would disturb the airflow around the
control surfaces rendering them inoperative. This is what is
referred to as compressibility.
Now a human body has no such control surfaces. And a person operating
a grav belt will be relying on the thrust of the belt for steering
more than he would on the air flow around him. So, there wouldn't be
any lessening of control in the region for any grav or space vehicle.
(No air control surfaces!)
(Orbital Lasers & Executive Action)
}Scott says:
}:Well, when you have a camera in orbit capable of resolving 10cm
}:objects on the surface, it's easy enough to correct fire.
}Getting this resolution would be a nighmare, Scott, if you're actually
}in orbit. Theoretical resolution limits @ your chosen wavelength.
}You'd have to set up a synthetic aperture arrangement with three
}(well two, but three would be better) or more ships. What DOD
}stellites do is dip into the atmosphere close to the target, get
}higher later. I *think* it's on the order of 1/2pi*w where w is
}wavelength.
Have you seen "Patriot Games"? That was what started me on this thread.
The satillite photographs they show there look to me as though they
have a resolution of 10cm. Now, the satillites aren't orbiting out at
50,000km true (short range for traveller starship combat) But still,
If we can do it at TL 8, they can pull the same trick at TL 15. Ok, as
Metlay pointed out X-Ray lasers are not the way to go, but a meson gun
could pick off individuals really easily.
Scott *2G* Kellogg
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