Jim Oberg,
Asbestos is actually less dangerous to humanity anf the environment
than the Owens Corning as well as the many other birth to grave
alternatives, and a similar argument can be made on behalf of R12
freon. However, at the time the likes of composite basalt and metallic
fibers was certainly worth looking into.

Of what was utilized instead of asbestos did in fact kill those
unfortunate astronauts.

Using expendable composite SRBs or far better yet, using ther much
lighter inert mass of what the LRB alternatives that existed at the
time would have been a win-win all the way around.

Therefore, it's time to re-focus upon the H2O2/RP-1 or better yet, upon
the H2O2/C3H4O LRB/LRM alternatives that's kg/kg worth 50% more payload
than any reusable SRBs, as still offering a good 25% better off payload
capability than most any disposible SRBs/SRMs. At least that's the
current SWAG of what I'm pulling from this following link.

This is what Steven S. Pietrobon and his friend Linder Metts have had
to contribute:

High Density Liquid Rocket Boosters for the Space Shuttle
http://www.sworld.com.au/steven/pub/lrb.pdf
The LRB has the same propellant mass as the shuttle SRB of 501.8t
Computer simulations indicate that payload mass can be increased by a
third from 24,950 kg
to 33,140 kg for a 28.45°, 203.7 km circular orbit.

The HTML (no copy) version of the
abovehttp://66.102.7.104/search?q=cache:d6RJz_mJX0gJ:http://www.sworld.com.au/steven/pub/...+1000+kg&hl=en
Space Shuttle Simulation Program
http://www.sworld.com.au/steven/space/shuttle/sim/

If mere replacement of the SRBs with the much less inert mass of these
LRBs of H2O2/Kero or I'm assuming RP-1 is what's good enough for such a
conservative 33% boost in payload, then without question the H2O2/C3H4O
should become worthy for nearly a 50% boost in LEO payload, and/or
achieving the same payload at roughly half the LRB mass, by way of
offering far better then a LOX/RP-1 match for achieving the maximum 1st
stage velocity and altitude, whereas considerably less inert massive,
and even remaining sufficiently exhaust velocity suitable for a 2nd
stage core application seems worth our looking into.

Sorry for all of my usual confusing words plus whatever's math that's
not always correct, or that of my interpretations of what's most
important isn't the least bit improtant to those that already seem to
know all there is to know. As I manage to learn more on this typically
need-to-know basis, at least I'll share without ulterior motives or the
sorts of hidden agendas that the vast majority of Usenet rusemasters
seem to be continually involved with.
-
Brad Guth