Peter Duniho wrote:
Robert Briggs wrote:

Peter, your grasp of the physics of the matter seems to be substantially
better than Don's (not that that is difficult), but I don't buy the bit
about "the scramjet [being] the *entire* source of the speed".

Todd's interpretation of my statement was exactly correct. This particular
scramjet had limited fuel available, and all scramjets have the limitation
that they only operate in supersonic flight. These limitations forced the
use of a bomber and support rocket. But the thrust generated *exceeded*
that provided by the rocket, which is why the scramjet was able to
accelerate after being released from the rocket.

Right.

The flight is a *proof-of-concept* for something which would require at
least one non-scramjet engine type to make a self-contained system.

Yes, it has always been understood that a scramjet by itself is not very
useful, since it can't be used from a standing start.

Agreed.

I simply think that your wording about "the scramjet [being] the
*entire* source of the speed", rather than its being "sufficiently
powerful to complete the acceleration to Mach 10" (or something to that
effect) is a tad loose.