Joann Evans wrote in message ...
Allen Meece wrote:

I think the PDE will scale up to make a flyback launch assister for a CATS
SSTO.
The site says the PDE is great between 2 to 4 machs and can take off from
zero speed so it offers a lot in the way of airbreathing launchers.

Who cares? Supersonic mated flight and seperation is too complex and
risky. Seperate subsonically (with existing 'first stage' aircraft, if
possible) at the highest altitude practical, to minimize drag and engine
expansion issues for your orbiter.

Hmm, the idea does sound interesting, though. If you had a TSTO which
separated at supersonic speed very high in the atmosphere, then even
though the PDE lower stage would careen and tumble away at high speed,
the PDEs could allow it to quickly right itself to return for a
controlled landing. The whole pulsed idea seems suited for dealing
with radical chaotic motion.

But the scramjet unfortunately isn't enough to get to orbit. You'd
need further rocket propulsion to take over after the scramjet.