🚀 go-pugleaf

In <1993Jan11.154812.235@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:

>A warhead re-entry vehicle is not a good model for a lander. A warhead
>doesn't attempt to do atmospheric braking. It's shaped like a long narrow
>cone, or hypersonic bullet.... A lander presents a blunt surface to the 
>atmosphere and tries to shed as much velocity as possible by atmospheric 
>braking. 

Ah, which lander are you talking about.  The Delta Clipper *is* shaped
like a bullet.  It does not present its blunt surface (base) on entry.
It makes a nose-first, high-angle-of-attack entry modelled after an
ICBM-warhead trajectory.  This was chosen because of the large amount
of data available from computer modelling of missile warheads.

It seems rather presumptuous to claim you know more than McDonnell
Douglas engineers working on the project about what is and isn't
possible when you are uninformed on such basic facts as this. 


>Shuttle designers originally
>considered a titanium skin for the Orbiter, but even a metal as refractory
>as titanium wasn't up to the job 

Yet Another Historical Error.  Refractory metals were up to the
job until NASA doubled the size of the Shuttle orbiter to meet 
military payload demands.  (And some engineers at Rockwell still
felt that refractory metals were viable, given sufficient ingenuity.
Langley, and possibly other NASA centers have since come up with 
refractory metals which they believe can do the job.  Some of these
were considered for use on the fifth orbiter.)