In article ,
says...

On Tuesday, November 13, 2012 8:44:40 AM UTC-6, Greg (Strider) Moore wrote:
http://www.businessinsider.com/aeroj...cility-2012-10

Anyone have more details?

...Jeff nailed this one, and I'd posed the same question on Secret Projects a few weeks ago, having palm-in-face forgotten that this question had show up around here quite a while back. Mark Wade's entry in EA sums the situation up quite well.

The document I linked to gives you an idea of just how hard handling
would have been for very large SRB's. Not only are the casings quite
heavy when empty, they're *extremely* heavy when loaded with fuel.
Ground handling equipment is necessarily sized to handle far higher
weights than for liquid stages, which can be fueled on the pad. Even
shuttle style SRB's, whose segments are sized for rail transport, give
handling headaches. The Aerojet solids would have been far too big to
transport by anything but barges.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer