Aerodynamics to protect shuttle ?

Would it be feasable to use aerodynamics to protect the shuttle from
foam and other debris ? If they added some fairings at strategic
locations, could it not direct airflow such that any debris would be
directed away from the tiles and RCC ?

John Doe wrote:
Would it be feasable to use aerodynamics to protect the shuttle from
foam and other debris ? If they added some fairings at strategic
locations, could it not direct airflow such that any debris would be
directed away from the tiles and RCC ?

Not really - for much the same reason fighter aircraft don't do this
to deflect bullets.
Any fairings would have to be huge, and create an enormous amount of
drag.
The debris is accellerated by the airstream going past the stack.
If you want to deflect stuff, you need a comparable amount of
momentum imparted to falling stuff, which means that you need the
air redirected to be going faster than the shuttle stack, for a
substantial distance.

Some years ago, I seem to recall this coming up. In scale tests, I know they
did check the transport of debris, but as far as I am aware, they were
interested in tiles then, as the counter intuitive possibility of a piece of
foam breaking an rcc was not considered possible. As we all now know, it is
possible.

The airflow between the belly of the orbiter and the tank/srbs is very
complex, mainly because of the speed ranges it has to fly in, and the
atmospheric pressure changes that occur.

I'd imagine trying to make some form of aerodynamic countermeasure that
worked in all eventualities would be at best, a compromise.

The thermal protection being so fragile is the problem with the shuttle.
Nobody would take any notice of the foam, if it were not for the proven
damage it can create in certain extreme conditions.

Actually, I feel that the real error in the design was not to include a
viable inspection and repair system from day one. After all, if you can fix
it, then you are not going to worry as much.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
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"John Doe" wrote in message ...
Would it be feasable to use aerodynamics to protect the shuttle from
foam and other debris ? If they added some fairings at strategic
locations, could it not direct airflow such that any debris would be
directed away from the tiles and RCC ?

Along this line, I've wondered about incorporating a "splitter plate".
That's to say imagine one big piece of say plexiglass parallel to the
vertical axis of the vehicle stack and between the shuttle and the ET.
It's purpose would be to separate the airflow so that foam coming off the ET
either stays between the ET and splitter or anything being deflected over
the splitter also deflects over the shuttle. If anyone is familiar with the
engine intakes on an F-4 Phantom, you might have an idea of what I'm
describing. On the F-4, the body of the aircraft near the engine intakes
are round. However, for reliable airflow into the intake a flat extension
keeps the airflow next to the rounded fuselage from getting into the
intakes. I'm talking about the fixed portion of the intakes in front of the
movable intake ramps, that portion of the intake forward of the inlet.

Of course I realize the weight penalty of any splitter plate material tough
enough to withstand debris impact will also take away payload, probably too
much payload so as to make the idea kooky.

--
Scott

In sci.space.shuttle, John Doe ordered an army of hamsters to type:

Would it be feasable to use aerodynamics to protect the shuttle from
foam and other debris ? If they added some fairings at strategic
locations, could it not direct airflow such that any debris would be
directed away from the tiles and RCC ?




There are a million and one ideas floating around the net from everyone
about how the Shuttles can be protected from damage. Whatever solution the
NASA engineers come up with will definately be the best solution possible.

Kokoro wrote:
There are a million and one ideas floating around the net from everyone
about how the Shuttles can be protected from damage. Whatever solution the
NASA engineers come up with will definately be the best solution possible.


That is what was said during the post Columbia period, with NASA saying
they were entirely confident the foam problem had been fixed. Clearly,
it wasn't fixed.

If NASA uses the same engineers, same management and same philosiphy in
tasking employees to find a solution, they may end up finding the same
solution that they did post Columbia. New blood and new ideas must be
enabled/empowered within NASA to come up with new ideas.