Hubble Question...

In article , wrote:
A hundred fold decrease in cost is a HUGE decrease...

Definitely so. That sort of massive improvement has never been done in
one leap before. On the other hand, to quote the late Max Hunter (chief
engineer for the Thor IRBM, later the basis of Delta), when that comment
was made to him: "The human race has never done anything as stupid as
we've done in space."

No major advances in basic propulsion science, i.e. no dilithium crystals,
impulse drive or anti-gravity engines nor is there likely to be. Chemical
rockets are going to be around a long time.

Probably so, but that doesn't mean that chemical rockets are in a state of
perfection which permits no major improvements. Too much of the accepted
wisdom in chemical rocketry is just the first thing that happened to work
when people were in a hurry in the 1950s. The alternatives are poorly
explored, and the current technology is in no way optimum.

Also, "nor is there likely to be" is gross hubris. If you added "soon" to
that, I might agree, with reservations.

No economies of scale and highly unlikely space craft will ever be mass
produced like Toyotas.

There won't be mass production of spacecraft without major improvements in
propulsion, which probably won't happen soon. But there is plenty of room
for somewhat lesser economies of scale. Having reusable spaceships merely
cost as much as major airliners would be a massive improvement... and
there is no clear reason why they couldn't, since they should actually
be simpler.

Since it is so expensive, only governments can afford to do it...

An increasing fraction of space launches are for private customers, and
there have already been privately-developed space launchers (a few).

If you assume that development of a reusable spaceship has to cost
billions and billions, then definitely only government can do it. But
that is an assumption, not a self-evident fact.

That's not to say costs can't be reduced, just that it is unrealistic
to expect a couple of orders of magnitude reductions.

I would say that a more accurate statement is that it is difficult to
*prove* that such a reduction is possible. The notion is not ridiculous;
even high-performance experimental aircraft typically operate at only
perhaps ten times their fuel costs... and that is *several* orders of
magnitude better than today's rockets. There is no obvious law of nature
which prevents reusable rockets from getting down into the same range.
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

In article ,
Derek Lyons wrote:
Couldn't we get close to it with a fleet of fully reusable shuttles that can
be operated and serviced like todays commercial jets?

Thats an open question. It took a lot of years and experience to get
commercial jets to where they are today.

Even operating and servicing like today's cranky high-tech experimental
aircraft would be an enormous improvement.
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

In rec.radio.amateur.space Henry Spencer wrote:
In article , wrote:
A hundred fold decrease in cost is a HUGE decrease...

Definitely so. That sort of massive improvement has never been done in
one leap before. On the other hand, to quote the late Max Hunter (chief
engineer for the Thor IRBM, later the basis of Delta), when that comment
was made to him: "The human race has never done anything as stupid as
we've done in space."

No major advances in basic propulsion science, i.e. no dilithium crystals,
impulse drive or anti-gravity engines nor is there likely to be. Chemical
rockets are going to be around a long time.

Probably so, but that doesn't mean that chemical rockets are in a state of
perfection which permits no major improvements. Too much of the accepted
wisdom in chemical rocketry is just the first thing that happened to work
when people were in a hurry in the 1950s. The alternatives are poorly
explored, and the current technology is in no way optimum.

I think we've progressed a bit beyond kerosene and LOX, but there are
probably further improvements possible.

Also, "nor is there likely to be" is gross hubris. If you added "soon" to
that, I might agree, with reservations.

While just about anything is possible, I highly doubt there will be anything
to replace chemical rockets (for launch from the Earth) ever. I give it
zero probability in the next 50 years.

I hope I'm wrong since there is nothing I would like more than to hop into
my space flitter and have a hamburger at the cafe on the Phobos, but I
don't believe it will happen.

No economies of scale and highly unlikely space craft will ever be mass
produced like Toyotas.

There won't be mass production of spacecraft without major improvements in
propulsion, which probably won't happen soon. But there is plenty of room
for somewhat lesser economies of scale. Having reusable spaceships merely
cost as much as major airliners would be a massive improvement... and
there is no clear reason why they couldn't, since they should actually
be simpler.

Lesser by a great factor. Successful aircraft are produced in numbers far
exceeding the number of spacecraft anyone would want (assuming no one
invents dilithium crystals).

The closest comparison available is the Concorde, which was a commercial
disaster and never recovered the development costs.

Further, if spacecraft became flyable by entities other than governments,
which are for the most part exempt from their own regulations, the
regulatory burden to certify the airframe for flight would run the cost
right back up and they would hardly be simpler as they would have to be
certified for both atmospheric and space flight.

One needs only to look at the time and cost required for certification
of a new, simple, piston engine driven aircraft to get a feel for this.

Since it is so expensive, only governments can afford to do it...

An increasing fraction of space launches are for private customers, and
there have already been privately-developed space launchers (a few).

The vast majority of "private" space launches use government vehicles.

There is yet to be a Orbits-B-Us private launcher that;

A) Works

B) Has significant cost savings

If there were, every satellite maker on the planet would be beating on
their door.

If you assume that development of a reusable spaceship has to cost
billions and billions, then definitely only government can do it. But
that is an assumption, not a self-evident fact.

Without dilithium crystals, it IS a self-evident fact. We've had space
flight for about half the time we've had flight, and the best we can
do is a few individuals with one off designs that at best will get a
person or two up and back just to set a record that cost millions.

The basic laws of economics prevail; if it were possible, someone other
than the government would be putting satellites in orbit and making a
buck or two in the process.

That's not to say costs can't be reduced, just that it is unrealistic
to expect a couple of orders of magnitude reductions.

I would say that a more accurate statement is that it is difficult to
*prove* that such a reduction is possible. The notion is not ridiculous;
even high-performance experimental aircraft typically operate at only
perhaps ten times their fuel costs... and that is *several* orders of
magnitude better than today's rockets. There is no obvious law of nature
which prevents reusable rockets from getting down into the same range.

No law of nature, but law of governments.

Are you aware that the Wright recreation had to get special exemptions from
the FAA to take place?

If the current regulatory burden were in place at the time of the Wright's
original flight, we would still be flying spruce and linen biplanes.

--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

--
Jim Pennino

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wrote:
No major advances in basic propulsion science, i.e. no dilithium crystals,
impulse drive or anti-gravity engines nor is there likely to be.

Until 2053 :-) (for warp drive, the rest will be transfered technologies from Vulcans)

That's not to say costs can't be reduced, just that it is unrealistic
to expect a couple of orders of magnitude reductions.

I agree entirely.

However, this brings a big dilemma: does one adopt a defeatist attitude and
stop looking for new and improved propulsion methods limiting humanity to
current rocket engines for the foreseable future, or does one continue to
research new propultion methods with failures until they actually come up with
something that works ?

How many rockets exploded/failed in the 50s and 60s until they got it "right
?" (heck, Ariane has had a lot of recent explosions).

The engine isn't the only story. Thermal protection is another big issue.

What seems to be stopping NASA right now is a religious choice between a
reusable vehicle and a simple capsule, and for reusable, whether it should be
winged or not, parachute or not.

In rec.radio.amateur.space John Doe wrote:
wrote:
No major advances in basic propulsion science, i.e. no dilithium crystals,
impulse drive or anti-gravity engines nor is there likely to be.

Until 2053 :-) (for warp drive, the rest will be transfered technologies from Vulcans)

That's not to say costs can't be reduced, just that it is unrealistic
to expect a couple of orders of magnitude reductions.

I agree entirely.

However, this brings a big dilemma: does one adopt a defeatist attitude and
stop looking for new and improved propulsion methods limiting humanity to
current rocket engines for the foreseable future, or does one continue to
research new propultion methods with failures until they actually come up with
something that works ?

One continues to refine and improve methods that conform to known physics
and hope that sometime, somewhere, someone in a lab says to himself "Gee,
that's weird" and comes up with something new.

How many rockets exploded/failed in the 50s and 60s until they got it "right
?" (heck, Ariane has had a lot of recent explosions).

How many airplanes crashed until they got it "right"? The US has had what,
3 spacecraft accidents where life was lost?

The engine isn't the only story. Thermal protection is another big issue.

What seems to be stopping NASA right now is a religious choice between a
reusable vehicle and a simple capsule, and for reusable, whether it should be
winged or not, parachute or not.

What seems to be stopping NASA right now is the choice between a non EPA
approved foam that works and an EPA approved foam that doesn't work.

--
Jim Pennino

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In article , wrote:

How many rockets exploded/failed in the 50s and 60s until they got it "right
?" (heck, Ariane has had a lot of recent explosions).

How many airplanes crashed until they got it "right"? The US has had what,
3 spacecraft accidents where life was lost?

There have been three accidents in the US involving the crew of a manned
spacecraft being killed whilst in the spacecraft; two in flight, one in
training.

There were two (three?) fatalities inside Columbia before STS-1 - two
technicians were caught in an area purged of oxygen - whcih you may or
may not feel falls inside your definition. There have also been
accidents in preparation of fuel, motors, &c; I don't have information
to hand, but they were in the 'manufacturing stages'.

What seems to be stopping NASA right now is the choice between a non EPA
approved foam that works and an EPA approved foam that doesn't work.

Except... this is a non-issue. The foam which didn't work, and didn't
work in a very spectacular manner last year, was the old "unhealthy"
foam...

CAB vol 1 pp51:

"BX-250, a polyurethane foam applied with CFC-11 chlorofluorocarbon, was
used on domes, ramps, and areas where the foam is applied by hand. The
foam types changed on External Tanks built after External Tank 93, which
was used on STS-107, but these changes are beyond the scope of this
section."
pp54:
"The Board has concluded that the physical cause of the breakup of
Columbia upon re-entry was the result of damage to the Orbiter.s Thermal
Protection System, which occurred when a large piece of BX-250 foam
insulation fell from the left (.Y) bipod assembly 81.7 seconds after
launch and struck the leading edge of the left wing."

Later, it discusses the effect of changing the foams:
pp129:
"The cause of the earlier-than-normal popcorning [on STS-87] (but not
the fundamental cause of popcorning) was traced back to a change in
foam-blowing agents that caused pressure buildups and stress
concentrations within the foam. In an effort to reduce its use of
chlorofluorocarbons (CFCs), NASA had switched from a CFC-11
(chlorofluorocarbon) blowing agent to an HCFC-141b blowing agent
beginning with External Tank-85, which was assigned to STS-84. (The
change in blowing agent affected only mechanically applied foam. Foam
that is hand sprayed, such as on the bipod ramp, is still applied using
CFC-11.)"

[In other words - the foam that was the root cause wasn't changed, and
the foam that was changed merely led the events to occur earlier rather
than start occuring. They were reduced to previously experienced levels
by STS-101]

I was sure there was a specific note about this somewhere, but a cursory
read-through hasn't found it.

[It's almost a pity it wasn't the EPA-induced changes that were the
cause - it could have made an excellent little parable about hubris]

--
-Andrew Gray

wrote:
The basic laws of economics prevail; if it were possible, someone other
than the government would be putting satellites in orbit and making a
buck or two in the process.

The problem is that the ecomonics of space flight are skewed by excessive
subsidies. Boeing likes getting paid $20 million for a window. Politicians
love to have all that money pumped into their state. And NASA works to make it
all happen.

NASA micro manages Boeing, but the government also micro-manages NASA, telling
it it can't develop this, can't implement that etc. The one potential great
advancement for the space station was Transhab, but that got specifically
canned by the government.

I am sure some people at NASA know how to modify the existing shuttles so that
they cost much less to operate/maintain. But NASA doesn't have the authority
nor money to implement this.

In rec.radio.amateur.space John Doe wrote:
wrote:
The basic laws of economics prevail; if it were possible, someone other
than the government would be putting satellites in orbit and making a
buck or two in the process.

The problem is that the ecomonics of space flight are skewed by excessive
subsidies. Boeing likes getting paid $20 million for a window. Politicians
love to have all that money pumped into their state. And NASA works to make it
all happen.

NASA micro manages Boeing, but the government also micro-manages NASA, telling
it it can't develop this, can't implement that etc. The one potential great
advancement for the space station was Transhab, but that got specifically
canned by the government.

I am sure some people at NASA know how to modify the existing shuttles so that
they cost much less to operate/maintain. But NASA doesn't have the authority
nor money to implement this.

So, all space technology is controlled by NASA and the US government who
conspire to ensure that no other entity on the planet comes up with cheap
space flight??


--
Jim Pennino

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