On Tue, 24 Aug 2010 07:02:36 -0800, Pat Flannery
wrote:

And it's got around the chance of flying in its finished form that
Dyna-Soar did. :-D

To explain that - Orion is too heavy as presently designed to get into
orbit on either a Delta IV Heavy or Atlas V Heavy.
Once the Ares 1 booster goes bye-bye, Orion has nothing that can carry
it into orbit; and Ares 1 is dead - so you now have a spacecraft that
can't be launched on any existing booster.

No, it isn't. Delta IV-Heavy can launch it once its upgrades (already
in the pipeline for a NRO flight next year I think) are in service.
And launching it on Atlas V-Heavy was LockMart's idea, so presumably
they know it can work.

Besides, the current plan is to launch it on something resembling
NASA's "Not Shuttle-C" proposal from last year. Or maybe something
like DIRECT. Either would be tentatively available in 2015, around the
same time Ares I would have been, in all likelihood.

Brian