(James Graves) wrote in message ...
Henry Spencer wrote:

And are hypersonics a good idea for anything at all?

For long-range flights across the atmosphere.

Interesting applications:
High-speed reconnaisance platform or Intercontinental bomber,
hypercruise missile.

Fast things are harder to shoot down.

An interesting factoid:
There used to be rumours the Russians had some sort of scramjet or
ramjet upper stage variant of the Topol-M ICBM when apparently the USA
radar network (?) detected an ICBM test with a really weird final
trajectory somewhere inside Russia. Turns out the Topol-M has a
maneuverable warhead to elude missile defense systems, but it still
uses Solid rockets.