On Sat, Jan 27, 2018 at 08:22:15PM -0500, Caleuche wrote:
> No matter how gentle a descent angle, there's no workable meteoric
> reentry profile for my 800 Dton 10:1 Cd=0.22 ship, when mass is set
> appropriately.

Yes, that sounds right.  If a ship with that mass is unpowered and
uncontrollable, then it's not going to survive a descent from orbit.
Even if it started with zero speed, it would hit the ground faster
than a rifle bullet.

> So I turned to the next obvious option: lifepods. Somewhere I had
> once seen a drawing of a Traveller lifepod intended for reentry that
> was not pressurized (and open to space even) which basically was a
> mass of ablative material on the front, with a space for the
> Traveller to lay down on immediately behind it.

That doesn't seem survivable.  You would want at least some shielding
from the radiative heat flux and later transsonic airflow around the
pod.

> The whole thing as probably on the order of 1-2 Dton, most of which
> was just a frame. It would include some means of propulsion to give
> something like a 20-40 m/s kick to deorbit it, and that would supply
> a low orbiting craft or space station a means of evacuating
> personnel.

Contragrav and thruster plates powered by energy cells would be a lot
safer and usable in many more situations, while adding very little to
the cost and volume.  It might still have heat shielding material in
case the pod needs to be ejected just before or during a meteoric
entry gone wrong.

- Tim