Re: How Rockets Differ From Jets

tomcat,
I fully appreciated your honest desires as to not roasting yet another
batch of astronauts, much less passengers, as that could represent a
rather serious PR situation and subsequent loss of financial investors.
>See my remarks above on hypersonic thermal heat. Read my lips: you
>will need cryogenic liquids to keep you cool during hypersonic
>atmospheric flight.
OK already, I'm lip reading but, it seems that I'm not nearly as smart
as yourself, so I might need a bit more than mere lips to go by.

The shuttle doesn't use such slush cooling of it's hull and, if all
goes sufficiently well because nothing gets broken or they're not being
utilized as a handy thermal feedback drone on behalf of yet another
DoD/ABL star-wars field test, it seems that of all other such things
being most pathetic about our shuttle is that it's primary inner
structural foundation of their hull is made extensively of aluminum,
that damn near melts just by looking cross-eyed at it.

Surely the 1000°C sustainable capacity of basalt fibers, microballoons
and of ceramic binders that can be further embellished with
internal/external layers of spendy CNT and then Corelle/ceramic coated
is worth looking into, that plus if still necessary the cryogenic value
of utilizing the fluid radon as phase-changing into a vapor/gas instead
of taking to much slush hydrogen along for the ride might seem
advantageous, especially since the Radium-->Radon breeder reactor needs
some place to temporarily store the produced liquid radon byproduct
anyway, before it's subsequently phased into a gas and utilized as
powerful ion thrusting.

>Think light and think hot, hot, hot. Also, think SSME's because . . .
>they work. I like things that work.
You're giving me the strong impression that your CNT Spaceplane as
having to be mostly that of a flying cryogenic tank of slush hydrogen,
and otherwise as a nifty rigid-airship as having a pathetic R factor of
4, or perhaps just R-2. Apparently you simply can't appreciate the
R-1024/m that's doable as a multi-task structural and insulative
composite of perhaps at most 128 kg/m3, which really isn't all that
heavy for a structural basalt composite worth of a tough inner/primary
shell which can take as much as a 1000°C thermal licking and keep on
ticking. As applied down to an average hull thickness equivalence of
0.25 m would represent 32 kg/m2 at the R Factor of 256, of which this
isn't even including whatever added benefits from the applied layers of
CNT, plus having an outer serviceable coating of Corelle/ceramics, of
which you'd think should only push the R-Factor a bit higher. Thus I
can't imagine the overall shell along with having the outer layers of
CNT and Corelle/ceramics getting this tally up to more than 48 kg/m2
(that's being all inclusive of internal bulkheads,
honeycomb/microballoon decks and all other framing considerations that
should be entirely of fire-proof and highly structural CNT/basalt, that
which shouldn't individually amount to greater than 32 kg/m3).

CNT question; Can you make microballoons out of CNT?
If you can't make CNT microballoons, then what's the CNT composite
R-Factor per meter, per cm or even per mm?

I actually believe that with good R&D is where a basalt composite of
fibers and mostly microballoons and of ceramic binders could get the
structural density, along with better than R-1024/m, down to less than
64 kg/m3.

>I 'like' the idea of ion thrusters. And, you have just pointed out
>that they could help with a 'retrofire' and 'reverse thrust' which are
>very important.

>Remember, however, that stopping a spaceplane going 200,000+ mph takes
>a lot of stopping. Even if you slow to 50,000 mph or less the reentry
>air friction heat will be . . . tremendous.
Obviously you'll have to slow down to something less than 7.8 km/s (say
17,400 mph), as otherwise you're not ever coming down. Thus how much
energy is that "slowing down" going to take per tonne?

BTW; by the time reaching Earth as arriving from the direction of the
sun, why the heck would the Spaceplane still be doing 200,000 mph (89.4
km/s)?
I would have thought it would be somewhat costing up-hill by having to
pull away from the likes of Venus and that other little pesky gravity
sucking item called THE SUN, thus getting slower until being sucked in
by the nearby gravity influence of Earth, which isn't going to
significantly happen as coming away from the sun until you're within
16r or less distance from Earth. With just the right amount of Venus
slingshot utilized should get the arrival back at mother Earth as per
arriving at whatever remaining velocity you'd think best manageable.

>The only exception would be if 'air spikes', electronic gizmos that can
>knock air molecules away from the hull, are perfected to the point that
>they really work. Then you would have the spaceplane surrounded by a
>vacuum even when moving at hypersonic velocity in the atmosphere.
Here's another SWAG(scientific wild ass guess):
Speaking about "air spikes"; What if the leading edges (most critical
reentry surfaces) were essentially 100% radon-->ion thrusters or
perhaps even just radon discharge accommodated?
Wouldn't such fast moving ions of such terrific mass and thereby
terrific KE worth of ion thrust react as somewhat fending off the
atmosphere, as well as providing their nearly continuous and thus soft
retro-thrust?

>A ridgid airship is precisely what a well built spaceplane is. Our
>'design engineers' don't seem to understand that. If you don't have to
>tether down the dry weight vehicle so it doesn't float off, then those
>engineers haven't done their jobs.
I agree. However floating off in Earth's thin and relatively low
density atmosphere plus rather substantial gravity isn't likely, unless
displacing all of the available interior volume with H2.

Spaceplane air conditioning via nuclear reactor; namely a small
multi-MJ U238/U239-->Radium-->Radon Breeder Reactor.

Pressurised radon gas as having been created within a high pressure
cooker of a Radium-->Radon Breeder Reactor, as a highly pressurized
decay containment cell of providing liquid phase Radon, which is then
routed through external heat-radiating cooling plates and, basically
short-term stored within high pressure receiver tanks as a liquid cash
that's 452 fold denser than Radon gas that's been cooled by whatever
the nighttime/shaded environment of space can manage to provide, from
which the refrigeration phase-shift into gas should represent quite a
bit of thermal energy transferring capacity.

Essentially your Spaceplane is in serious need of being as much nuclear
powered as possible, at least as being supplemented with the byproduct
of Rn222 that'll be utilized as Spaceplane shell cooling as well as
fuel for accommodating all of those ion thrusters. I'm thinking this
ion thrusting process could require several hundred MJ worth of applied
energy, as there should be dozens of these fairly large (0.1~1.0 m2)
Radon-->ion thrusters involved, and that's going to take a good supply
of Rn222 plus the neceaasey MJ worth of applied electrons for creating
all of those fast moving ions.

BTW; Airbus A380 supposedly carries 30 metric tonnes worth of
structural composites, with a gross empty/dry mass of nearly 280
tonnes, and a gross takeoff mass that'll soon exceed their original
design limit of 590 tonnes (slush C12H26 fuel could easily add 10
tonnes).
~

Kurt Vonnegut would have to agree; WAR is WAR, thus "in war there are
no rules" - In fact, war has been the very reason of having to deal
with the likes of others that haven't been playing by whatever rules,
such as GW Bush.
Life upon Venus, a township w/Bridge & ET/UFO Park-n-Ride Tarmac:
http://guthvenus.tripod.com/gv-town.htm
The Russian/China LSE-CM/ISS (Lunar Space Elevator)
http://guthvenus.tripod.com/lunar-space-elevator.htm
Venus ETs, plus the updated sub-topics; Brad Guth / GASA-IEIS
http://guthvenus.tripod.com/gv-topics.htm

.

Relevant Pages

  • Re: How Rockets Differ From Jets
    ... > structural foundation of their hull is made extensively of aluminum, ... > of utilizing the fluid radon as phase-changing into a vapor/gas instead ... The exact same amount of energy it would take to get the spaceplane ... > ion thrusting process could require several hundred MJ worth of applied ...
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  • Re: Size of the proposed "new" space vehicle?
    ... at least as much as a 2 kg item, thus capable of allowing the CNT ... might suggest the worse possible events if the spaceplane is making ... fibers of a composite basalt are individually worth 4.84 GPa in tension ... Basalt Continuous Fiber Mechanical Properties ...
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  • Re: How Rockets Differ From Jets
    ... as I was thinking of your CNT covered basalt composite ... Spaceplane taking 10 minutes for this transition. ... If going to Venus is to orbit and get into rigid-airship mode of ...
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