$64 Billion and seventeen years to land on the moon. What's wrong with this picture?

"William R. Thompson" wrote in message
...
Jonathan Silverlight wrote:

William R. Thompson writes
Pat Flannery wrote:

As I mentioned above it's primarily to get the peroxide to react and
decompose. Another way to make H2O2 decompose is pass it though fine
pellets of silver.

Or silver coins. Back in the early Sixties I used dimes to get
hydrogen out of 3% hydrogen peroxide solutions. I never did
generate enough hydrogen to fill a balloon.

I thought that when hydrogen peroxide decomposed it went to water and
oxygen. It's an oxidising agent, not a reducing agent, surely?

Now you know why I never became a chemist. I must have the memory
confused with one of those other junior-scientist experiments I
ran with test tubes and 25 cent bottles of "Perfect" chemicals
from the local hobby shop.

Bill, you can use dimes to generate hydrogen from hydrochloric acid,
"spirits of salts". Perhaps this is what you remembered.

Neil Gerace wrote:

"William R. Thompson" wrote:

Now you know why I never became a chemist. I must have the memory
confused with one of those other junior-scientist experiments I
ran with test tubes and 25 cent bottles of "Perfect" chemicals
from the local hobby shop.

Bill, you can use dimes to generate hydrogen from hydrochloric acid,
"spirits of salts". Perhaps this is what you remembered.

Probably; I was always looking for something to use as a rocket fuel.
Solid, liquid, gas, icky--I wasn't too fussy, or too competent. It's
no doubt a good thing that I couldn't get my ten-year-old hands on
anything that would have worked. Although the vented foil nozzle
on the hydrogen balloon might have been interesting, in a way . . .

Model rockets were around at the time, but California law made it
almost impossible to obtain and fly them. I have a vague memory of
a paper with lots of fine print that detailed state law on the subject.
Basement bombers had done enough damage to themselves in the late
Fifties to make the Legislature err on the side of caution.

--Bill Thompson

On Fri, 19 Mar 2004 08:49:13 GMT, "William R. Thompson"
wrote:

Bill, you can use dimes to generate hydrogen from hydrochloric acid,
"spirits of salts". Perhaps this is what you remembered.

Probably; I was always looking for something to use as a rocket fuel.
Solid, liquid, gas, icky--I wasn't too fussy, or too competent. It's
no doubt a good thing that I couldn't get my ten-year-old hands on
anything that would have worked. Although the vented foil nozzle
on the hydrogen balloon might have been interesting, in a way . . .

Hmmm, when I was a kid I'd put a lye solution in a Coke bottle, drop
in some aluminum foil and fill balloons stretched over the bottle's neck.
Worked real fast, but generated alot of heat. I never thought of rigging
a nozzle up to the balloon- I'd just put fuses on some of them so they'd
explode in flight. Others I'd put notes on with my address. I got a reply
from somebody several hundred miles away once

Dale

"Dale" wrote in message
...

Hmmm, when I was a kid I'd put a lye solution in a Coke bottle, drop
in some aluminum foil and fill balloons stretched over the bottle's neck.
Worked real fast, but generated alot of heat. I never thought of rigging
a nozzle up to the balloon- I'd just put fuses on some of them so they'd
explode in flight. Others I'd put notes on with my address. I got a reply
from somebody several hundred miles away once

I was much less adventurous. I made hot air balloons with firelighters, a
plastic rubbish bag and some wire to hold the bag open and attach the
firelighters in the opening. When lit, the bag just floats up and away.
Quite a spectacle at night, can be seen for a long time, especially if
there's not a lot of wind.

Dale wrote:

Others I'd put notes on with my address. I got a reply
from somebody several hundred miles away once


I made a mini-Skyhook by putting a helium balloon inside of a cellophane
laundry bag; the idea was that when the altitude was high enough that
the balloon burst, the helium would stay in the bag and it would
continue in flight- this must have worked, as it took off going
South....but ended up a total of 480 miles away, up North in Canada.

Pat

Neil Gerace wrote:

I was much less adventurous. I made hot air balloons with firelighters, a
plastic rubbish bag and some wire to hold the bag open and attach the
firelighters in the opening. When lit, the bag just floats up and away.
Quite a spectacle at night, can be seen for a long time, especially if
there's not a lot of wind.


When my parents were kids, they used to sell paper balloons that used a
candle to do the same thing....many fires were started this way. =-O

Pat

(dave schneider) wrote:
I understand fully that the Shuttle is not the only possible reusable
design. From what I've seen of other reusable designs (none of which
have flown yet), we don't have good answers for the hard problems of
reusables. X-33 has hard problems. OSP WVs have hard problems. Some
of these are mitigated by lifting body designs. Some of these are
mitigated by reusable capsules (none of which have flown).

I've never claimed that hard problems didn't exist. My position is
simple; Putting off the hard bits doesn't make them easier, and don't
confuse the Shuttle with a re-useable system, it isn't.

There are good reasons to have reusable vehicles once the flight rate
crosses a threshold; is that threshold 10-20 flights? Most of us
agree not. Is that threshold 50-150 flights? Maybe, but our current
data point makes us suspect not. 1000 flights? Now we're talking.

The number at which crossover is reached is strongly bound to the
design, implementation, management, and operations of a single design
that it's really almost impossible to define a generic number. It's
quite possible to operate a cheap craft below the crossover, even when
you should theoretically be above it. The bean counter and PHB stuff
rarely discussed in these forums matter a great deal there.

Do we have good answers to the hard problems of reusable in our
current data point? No, although the answers we did have allowed us
to get by with a large standing army. The recent proposals for
reusable vehicles have better answers, but my understanding is that
there will still be a large standing army needed.

Well, we *don't* have a data point on re-useables, as one has never
flown beyond the DC-X. (And at that the DC-X was really a
refurbishable, but far closer to reuseable than the Shuttle, which is
a refurbishable, and not really a reuseable at all.)

The presence or absence of a standing army is a factor of design, not
a factor of the reusability. To date expendables requires not one but
*two* standing armies, one at the manufacturing plant, and one at the
launching site. For a true reuseable, the first army goes away at the
end of the production cycle.

There are a lot of interesting ideas for reusable vehicles, but I am
still waiting for evidence that we can address the hard problems
profitably.

And you'll wait forever if progress towards solutions is limited to
paper and Power point.

As to why earlier in the thread I was talking about OV-20x, it is
because it pertained to *your* comment about the size of the change in
vehicle vs the amount of effort to implement, and how that affected
the payoff of the change. I don't see that responding to your comment
is irrelevant.

You never see why want you want to discuss is irrelevant because you
keep focusing on the Shuttle rather than the larger issues. You
*keep* returning to the Shuttle to avoid addressing the hard points.
You do it *again* right here in the message I am answering.

In any case, I think the near-future involves step-wise approaches to
reusability. Eventually, we will know enough to put it all together.
I don't reject reusability out of hand, as *you assume I do*, but I'm
still waiting for evidence that we can succeed at it now.

''Still waiting for evidence '' + ''constant comparisons with existing
non-reusable craft like the Shuttle''+ ''unwillingness to look at the
deeper issues'' == "Dismissal out of hand". It's not so much *what*
you say as *how* you say it, and your constant obsession with
diverting the conversation away from the issues.

To repeat your comment:
I've *tried* to convince you. But you dodge addressing the points I
raise, and substitute criticism of the Shuttle for a discussion of the
merits of reuseables vs. expendables, and the engineering and
philosophy behind both.

No, you did not try to convince me. You merely accused me of
anti-reusable dogma. You presented no data, no arguments, merely a
"Me Tarzan, you Wrong" attitude. "Naughty, naught capsule person".

See my paragraph above.

You did not refute my contention that TPS is an issue (I acknowledge
that Kim Keller reported that it was not an issue for OSP, but I still
think Ray Schmitt indicated that a large standing army is needed for
those designs, too).

Duh. Did it ever occur to you *that means I agree with you*? All I
ever tried to do was break your bizarre linkage between scramjets and
TPS.

You didn't provide evidence for reusable motors that overcome the
issues of the SSMEs.

See my reply to you in s.s.p., where I pointed out to you that the
SSMEs are first generation systems, and there is little-to-no work on
successors. In the same reply I point out the design philosophies
that lead to the current problems.

You did argue that the weight of the wings was justified because of
the cross-range capabilities they provide; I agree that the
cross-range is valuable, but for many return missions the cross-range
can be traded for timing of reentry.

Except of course for the families of missions where you can't.

As a specific example, returning the CMGs from ISS...they wouldn't be
significantly affected by a day or two extra in picking the burn time.

That's one example. It's also non-representative. Manned capsules
are a very different story.

D.
--
Touch-twice life. Eat. Drink. Laugh.

"Pat Flannery" wrote in message
...


Neil Gerace wrote:

I was much less adventurous. I made hot air balloons with firelighters, a
plastic rubbish bag and some wire to hold the bag open and attach the
firelighters in the opening. When lit, the bag just floats up and away.
Quite a spectacle at night, can be seen for a long time, especially if
there's not a lot of wind.


When my parents were kids, they used to sell paper balloons that used a
candle to do the same thing....many fires were started this way. =-O

Probably wasn't a good idea of mine to launch it in a forest, then.

Neil Gerace wrote:



When my parents were kids, they used to sell paper balloons that used a
candle to do the same thing....many fires were started this way. =-O



Probably wasn't a good idea of mine to launch it in a forest, then.


Mr. Ashcroft! He's right over there! And he was chanting verses from THE
KORAN! I think he's some sort of ELF/Al Qaeda/ACLU operative! LOOK! He's
reading that tree its Miranda Rights! IN ARABIC! :-)

Pat

On Mon, 15 Mar 2004 20:04:04 GMT, Eric Pederson
deZ to respond wrote:

The ultimate for a non-toxic, storable, moderate thrust system would be
spark or hot wire ignited NOX/alcohol.

I'm curious, why would alcohol be used instead of kerosene?

--
"Sore wa himitsu desu."
To reply by email, remove
the small snack from address.
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