Space Forum / Space Flight / September 2003

I have been contemplating various reentry options for my imaginary air
breathing SSTO vehicle. If I can solve the problem of going to orbit
by using an air breathing engine in the beginning until mach 8 and
switch to hydrocarbon (propane-LOX)rocket propulsion to go to orbit it
would be nice to have a good reentry strategy.

I read the article again in the Nov 2000 popular mechanics that
describes the air force's saucer shaped orbital vehicle called
Lenticular Reentry Vehicle.

It seems to me that the saucer shape has many advantages, namely low
drag, good lift, large usable interior volume.

Now I am wondering if I can just reenter with a vehicle like this and
use a shallow reentry profile, to spread the heat over a longer time,
to reduce the heat load on the structure.

The other alternative I am contemplating is to use an air scoop to
collect air during reentry and use one or more air breathing engines
to more quickly decelerate before I get into the denser atmosphere.
Basically if I gather some air in the upper atmosphere I can use the
air breather to loose my orbital velocity and then just drop down to
earth without all the heating. The fuel used is not terribly much.

Zoltan