Re: Sharing Models, was: Intestinal Fortitude

From: Adrian Tymes (
Date: Sat Mar 17 2001 - 12:49:29 MST

Spike Jones wrote:
> Adrian Tymes wrote:
> > Spike Jones wrote: Suppose you
> > > are a rocket designer and you are given the same set of requirements
> > > the shuttle designers were given in 1965. To orbit with 30 tons,
> > > 18.5 meters by 4.8 cylindrical, *return to earth with 10 tons*
> > > and land with dignity. What would it look like? spike
> > Adrian Tymes wrote: Using 1965 tech, I assume?
> No I meant with every trick we now have.

Oh. Well, in *that* case... ^_^

As before, plus:

* Use something with *far* higher specific impulse (probably one of the
  "new generation" thrusters, rather than explosives, partly so that
  you don't run the risk of an engine fault blowing up your vehicle),
  enough that you can do a powered abort from any point in the launch
* 100% fly-by-wire.
* Tailless plus thicker wings if you can get away with it: non-cargo,
  non-cockpit bits can be put in the wings.
* Maybe go for windowless "glass cockpit", to improve shielding and
  aerodynamics. Split pilot and copilot between the wings, so as to
  use the entire central body for cargo and surround them with more
  displays. Make *very* certain to have redundant and reliable cameras
  all over the vehicle's exterior, since this does dispose of the
* Horizontal takeoff and landing, such that it can use and be serviced
  at commercial airports (renting hangar space at which is far cheaper
  than renting or owning special spaceports; this also provides a far
  larger number of possible landing and launch sites, and a path for
  airlines to incorporate this vehicle into their fleets, thus
  providing a significant market for volume production - and cheaper
  incremental improvement/development - of the vehicles after the first
  few enter into service for the initial developer).
* Better (lighter/stronger) structural materials, possibly composites.
* Just to one-up the shuttle, enlarge the cargo volume slightly - only
  an extra half meter or so in diameter, enough that people can design
  satellites to this vehicle's specs rather than the shuttle's. (Say,
  spy satellites, whose accuracy is limited by the diameter of their
* No explosive bolts. No explosives anywhere on the craft. To the
  greatest extent possible, all parts designed to be useable again and
  again, rather than only once, and thus more likely to work right when
  they are used - even if no one ever services them. (Which means
  people don't have to service them ever, which drives down maintenance
* All electric if possible, or at least heavily favoring electric
  motors and actuators as the primary means of translating control
  signals into action. (Electric vehicles, at least on sea and land,
  have proven to need far less maintenance than just about any other
  type of high-performance vehicle, primarily because they use less
  parts - thus, less things that can break during use, less things to
  fit together during design, and less things to check when prepping
  the vehicle for use.)

> > Much the same, but fully RLV - no external
> > tanks or external solid boosters.
> ...Which is the effort that was just declared a failure, the Venture
> Star/X34. The technology to do a fully recoverable just
> isnt quite there yet, or at least not as a single stage to orbit.

Fully recoverable with standard fuels, yes. One of the main causes
appears to be the high mass fraction incurred by such. Note what NASA
is shifting the former Venture Star/X34 funding to. An argument could
also be made that the contractors building the Venture Star/X34 had a
financial interest in failure of same.

> > [a bunch of good ideas snipped]
> >
> > They say you can't argue with success. I say you can improve on it.
> Hope so. {8-] spike

This goes beyond theoretical for me, actually. I'm trying to see how
it would be possible to really build one. Two main problems come up:

1. Engine tech - RLVs appear possible with today's technology, save for
one element: far better rocket engines than the explosive fuels in use
today. Thus, an effective RLV development plan necessarily includes
development of said better engine. Plasma is the primary candidate I'm
investigating, but not the only one. (This includes power sources,
since a number of the promising candidates require having a lot of
electrical power on the vehicle itself for the engine to use;
transmission from outside runs into problems with, among other things,
using commercial airports.) I may have to build this myself, though I
suspect there may be groups already working with similar devices that I
can pay to build it for me, and probably do a far better job of it than
I could...but I have to find them before I can ask.

2. Funding - I'm not a millionaire. If I can get a decent RLV dev plan
together, I may be able to weave it into a business plan and get VC or
angel money, but I need to find out the order of magnitude cost for
each element of that plan. (Of course, if I can get this effort off
the ground, so to speak, I may well become a millionaire once this hits
volume production. However, getting the technology into public use is
more important, to me, than fame and fortune - but driving this myself
may be the only way to get it done, given as most/all of the other
efforts seem stuck on using existing engine tech. I could be wrong
about the necessity of that - but, if I am, then there are enough
people trying to make RLVs with the older engines that someone is
likely to suceed if it is possible, so I'd be wasting my time using the
older tech anyway.) So far, the most promising model seems to be if I
can act as a coordinator between the groups developing each part of
the puzzle, but many investors might see said plan, wonder what I'm
contributing, and try to run it themselves - and, driven by short-term
greed more than desire to develop cheap space access, fail to satisfy
either goal.

I've been working on these for a while, and I probably will continue to
work on these for some time.

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