Space Travel by Humans is Possible

Einar wrote:

:On Jan 22, 11:34 pm, Fred J. McCall wrote:
: Einar wrote:
:
: :
: :Simply because inflatable objects simply prove so darn useful they are
: :bound to become dominant, once the initial infant phase in theyr use
: :is past.
: :
:
: Have you considered MAWs? It seems to me that something like the
: 'shuttlecock' approach used for Spaceship One, but with the 'feathers'
: being MAWs would work and you don't have to worry about 'inflatables'.
:
: Of course, MAWs are a 'not yet existing' technology, too.
:
: But there are other approaches that could be used until then. The
: sort of gas boundary heat shield we've already talked about could be
: made to work. Assembled heat shields could be made to work.
:
:Hmm, not sure which MAW you are talking about. There appear to be many
:things out there with that acronym. One of the interesting ones is an
:experiment named 'Mission Adaptive Wing' which was tested by Nasa on
:an f - 111. A wing which warped, somewhat like pre WW1 wings tended to
:do, except in a somewhat more advance manner.
:

That's just the beginning. A true MAW would radically change shape
throughout flight, maintaining optimum characteristics throughout the
flight regime.

This one is a long way away, though.

:
:Gas boundary heatshield, not sure either what that supposedly is,
:except perhaps you are referring to the idea to spray water from an
:internal source on the heatshield of the spacecraft in order to reduce
:ablation. However, that is not an obvious method in creating greater
:drag...which is the problem of Mars entry.
:

That's because you didn't understand it. This is essentially the
'engines lit' tail-first reentry. The engine exhaust acts as a heat
shield and the engine thrust reduces your speed. This is probably no
more difficult to make work than any other approach, since it's just a
matter of aerodynamic flows.

:
:
: Simply
: building your vehicle to have some aerodynamic control and staying up
: high where you get the advantage of the atmospheric scale height until
: your speed comes down could be made to work.
:
:
:To be effective in Martian athmospher they´d need to be substantially
:larger than those used over here. Essentially you might be talking
:about some sort of a shuttle type of a veicle, but with subtantially
:larger wing area per overall weight, yet designed to land vertically.
:
:Possible, but tricky to design, and the aerodynamic surfaces or wings
:would be a large weight serving no useful purpose till upon landing.
:

Think a bit outside the box. Picture something like SpaceShip One's
'shuttlecock' design, but with bigger 'feathers' that can unfold.
Essentially a big part of your 'heat shield' is folded back along the
length of the vehicle and unfolds to provide lift and drag.

:
:
: There are no 'single point technology failures' in pretty much any
: endeavour you care to name.
:
:
:Hmm, the most simple solutions appear to be an assembled in orbit
:heatshield and inflatable heatshield named hypercone. Neither would
:require a dramatic new type of a design for a landing craft.
:

Neither do a gas-boundary heatshield or a shuttlecock design. The
'assembled in orbit' heatshield is probably easiest, but it's also
somewhat less adaptable than the others. The 'shuttlecock' design may
actually be easier than the 'hypercone' and is more adaptable to boot.
The gas boundary heatshield is probably the most technically
challenging, requiring a lot more flow studies than the others, but is
also the most adaptable of the four.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw