Another Thought...

Hello all:
I have thought up another idea I would like to share with the
members. I would appreciate it if you would look at it and poke holes
in the concept. Hopefully, after poking said holes, you can offer
suggestions or "fixes" for what you find wrong. I came up with this
concept while typing a reply to a post from one of the members and
took a couple of days to think about it. I know that some of this
will be old news but the questions I have are; Whatever happened to
the ideas? And, are these ideas worth re-visiting?

While talking with Michael about cutting costs for space launches, I
mentioned the thought that possible modification or adaptation would
help to reduce costs sufficiently to become attractive to financiers.
So, I started to think about ways we could reduce cost on something
like a space shuttle launch.

We know the primary reason for those launch costs is the method of
launch. Not only does the current methodology require the lifting of
tremendous amounts of dead weight, but we must also launch vertically
from a standing start. Which means we have to overcome not only
gravity but inertia as well. So, obviously, the best way to cut
overall costs, is to cut out those procedures which cost the most:
get rid of the external tank and the dead weight of the associated
plumbing, circumvent the effects of inertia, and use centrifugal
force to mitigate the force of gravity. Yeah! Like these are new
ideas.

"Official" space (i.e. Governmental Space Programs and Aerospace
Companies) were working on conceptual ideas to get around those
costly methodologies by developing a horizontally launched spaceplane
that can use just about any airport. Whatever happened to that
program? Although, if I am recalling correctly, wasn't that program
only to create a ballistic arc aircraft? It was only intended to fly
at very high altitude, touching but not really entering space, wasn't
it?

Anyway, what if we were to redesign the STS Transport system? Meaning
the converted 747's that used to haul the shuttles from Edwards
(Calif.) back to Kennedy (Fla.). I am thinking about replacing the
engines with something from say SR-71. Not to make them go faster,
that would take a complete redesign of the whole airframe, but to
make them capable of reaching much higher altitudes. Using Ram Jets,
the aircraft could conceivably reach altitudes of 60, hopefully as
much as 80+, thousand feet, while still cruising at right around 600
knots. More importantly, by limiting the speed of the aircraft, it
could achieve this while carrying the shuttle on its back. Of course,
there may have to be some modification of the wings and aerodynamic
aspects of the aircraft as well.

Of course, the Shuttle itself would also have to undergo redesign.
Can someone tell me why the shuttle cant be fitted with multiple fuel
tanks in the body and wings like other transport craft? That would
have bearing on this whole concept. Anyway, putting that aside for
the moment, the redesign concept of the shuttle has it undergoing
engine, fuel system, and wing replacement. But I am going to discuss
them in reverse order.
Wing Replacement- The wing would be elongated, making the overall
width of the spacecraft slightly larger. The extra space would make
the addition/enlarging of wing tanks possible. It would also have to
be moved upward in reference to location of the wing root on the
fuselage body. Thus, creating a sort of "keel" on the fuselage and
allowing Solid Rocket Boosters (SRB's) to be directly attached under
the wing root. This modification could also enhance the Aero-braking
aspects of the shuttle; although the effects of frictional heat would
have to be researched.
Fuel System- Eliminate the external tank and all of the dead weight
plumbing that goes with it. Fill that, and any other space in the
body and/or wings, with fuel tanks. Then, switch from the use of
separated fuels (held in separate tanks and mixing only in the
combustion chamber) to combined fuels (fuel and oxidizers which mix
well under normal temperatures but become highly combustible at high
temps.). Fill all of the shuttle's tanks with this combined fuel,
save 2-4 of the smaller tanks (maybe the outer wing tanks). These
will be filled with high performance jet fuel (JP-5 or -6).
Engine Design- Existing engines would be scrapped in favor of a dual
purpose engine design. Meaning it would have to act as both a jet
engine and a rocket motor. This may be possible with the use of
multiple afterburners. In stage one (jet), the engines would draw and
burn the JP fuel for the purpose of matching speed with the lifter
aircraft and maintaining speed after breakaway. Drawing oxygen from
the surrounding atmosphere via ram induction, the spacecraft would be
able to accelerate through Supersonic speeds and initiate orbital
climb out. This would be accomplished through the first stage
afterburner. As the jet engines reach their maximum effective
altitude, the spacecraft will enter;
stage two (rocket). The second stage afterburner is ignited, using
combined fuels. This also triggers the ignition of the SRB's which
should carry the ship into orbital altitudes. And should be able to
do so with fuel to spare.
At mission's end, the shuttle would enter into the de-orbit maneuver
with which we are all familiar. Using an aero-braking glide through
the upper atmosphere. At an altitude of 70 thousand feet (splitting
the difference between possibility and possibly wishful thinking),
the pilot can open the air intakes and restart the jet engines.
Allowing the ship to land with better control and higher safety
margins.

I realize that a lot, if not all, of this is old hat and has been
discussed before. Plus there are a lot of questions which require
answers to make this sort of thing work. But would it not make for a
drastic cut in launch costs? Therefore, making its use in a
commercial space program feasible. Further, justifying research into
its potential.

Just a thought.

Thank you for your time.

Patryk