Air-breathing hypersonic engines

Al Globus wrote:

>Using dry weight to thrust ignores the main advantage of a scramjet --
>it doesn't carry the oxydizer.
>
It does if it wants to get to orbit- you can't just fly out of the
atmosphere straight into orbit. Also, note that all the practical
scramjets use liquid hydrogen for their fuel; so you still have deeply
cryogenic fuel for the vehicle.

> A more meaningful measure is wet weight
>to thrust.
>
Not in isolation. It's not about metrics, it's about systems. Americans
tried to build something like this 15 years ago, they failed. Hypersonic
aeroplanes have been a research topic for about 30+ years; and doesn't
appear to have made very much progress. The most successful hypersonic
vehicle is the Shuttle, and by a very long way (unless there is some
black project that nobody is talking about.)

>Al Globus
>CSC at NASA Ames Research Center
>http://www.nas.nasa.gov/~globus/home.html
>
--
-Ian

Motto: "You're Not Authorized to Know Our Motto."
So, like, how many lives DOES Shroedinger's cat have anyway?