In article ,
Pat Flannery wrote:
...and concede that the Porklauncher IB has to have three
stages, and the second has to be LOX/kerosene rather than LOX/LH2...

I'd like to see that one- if this thing's the stick; that one would be
the pencil.

It actually might end up shorter, given how much denser LOX/kerosene is.
That's the point: a relatively compact LOX/kerosene stage plus a *small*
LOX/LH2 stage. (That said, I haven't actually run numbers on this one.)

they've got a choice between using an EELV variant for crew launches, or
biting the bullet and going straight to the Porklauncher V. I'd guess
they will do the latter, just because the former smacks much too much of
admitting defeat.

Ares V is way-too-capable of a vehicle for earth orbital missions,
unless you are going to build a very large space station.

So what? If you're going to need it anyway, it's cheaper and easier to
launch it with a CEV and a tub of ballast than to develop and operate a
second rocket just for LEO missions.

(You leave the ballast on the station. Space stations *want* to be heavy,
not light -- extra mass reduces the effect of air drag and lengthens the
interval between reboosts, without changing the average annual reboost
fuel consumption.)

I think in fairly short order the new Congress is going to go looking
around for things to cut out of the budget, and this particular space
program will be one of them.

The support for shuttle replacement is pretty bipartisan. If the
Porklauncher V was *the* rocket for shuttle replacement, it would be
fairly safe. It would be in a stronger position if it had been the chosen
rocket all along, but I think they could still get away with making the
switch now. (They can't wait too much longer, though.) What might get
cut, or at least postponed, is an expensive new rocket that's needed
*only* for beyond-LEO operations.
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