Overpopulation

this is true, but there are a couple of points that you have missed.

1) the launchers would be done in high altitude mountains, not at sea
lvl. for this reason there is less atmospheric pressure, thus less
heat.

2) it would only be done in regions far from cities, there for not
much risk of damage from sonic booms.

3) the shuttle uses the atmosphere as a break, therefore it goes
though a lot of it, this causes a build up of heat. in a launch of
this type, your trying to get our of the atmosphere as soon as
possible, so you would only be dealing with the heat for a maximum of
35 seconds, where as the shuttle has to deal with it for many
minutes. with a sharper line, it would have less drag, thus less
friction. with a properly designed nose and leading section, the rest
of the ship would have little or no (relatively speaking) heat to
deal with

4) a large about of the shuttle and other ships frontal cross
sections are created by the fact that they have to carry huge amounts
of fuel. if a ship can launch with sufficient speed to not need fuel,
save for maneuvering, it can be considerably more streamlined.

--- In spacesettlers@yahoogroups.com, "Lucio de Souza Coelho"
wrote:
>
> On 5/22/06, panamabob@...
> wrote:
> > but rockets today don't go through the majority of the atmosphere
at escape velocity.... start slow and speed up progressively...
sendinga item off a rail accelerator suggest that it would have
attained escape velocity + because friction would make it lose part
of its umph along the way. escape velocity, some 7 miles per second
seems to me to create some serious friction issues.
> (...)
>
> In fact current rockets reach escape velocity when they are already
> well outside the atmosphere. Consider a "didactic" case where the
> rocket accelerates vertically at 3g until reaching escape velocity.
> That would happen at an altitude of more than 2,000 kilometers. In a
> realistic case (like the Apollos going to the Moon), first the ship
> enters orbit, and then accelerates to escape velocity.
>
> And yes, launching something from the Earth surface at escape
velocity
> would create serious friction issues - *much* more serious than the
> ones faced by ships reentering atmosphere. In the case of spacecraft
> reentering, atmosphere starts very thin and then goes thicker (which
> means that the craft reaches the thicker layers at lower speeds),
and
> the reentrance angle is very shallow in order to prevent
overheating.
> In the case of spacecraft shot from Earth surface at escape
velocity -
> basically a meteor turned upside down... - the craft would get the
> thickest of atmosphere first, at maximum speed and (I suspect) at a
> straight angle!
>
> That said, I would not be quick to deem that impossible - but it
would