CEV to be made commercially available

Henry Spencer wrote:
In article . com,
Jake McGuire wrote:
Most commercial transportation seems to come out somewhere in the
neighborhood of 7 times fuel costs. Or at least airlines and trucking
companies do...

Note, though, that magically (say) doubling the fuel capacity of an
airliner would not double its operating costs; most of them don't scale
with fuel use. Rockets ought to have *lower* ratios than airliners, in
fact much lower, because they are so much more fuel-intensive, and fuel is
the easy par

...maybe $100 per pound if you can get payload up to 10% of dry mass.

You should be able to do better than that. The DC-Y proposal put payload
at about 15% of dry mass; it was an aggressive proposal, yeah, but it also
had all the dry-mass overheads of LH2.

Of course, the DC-X wasn't even in the same universe as operations
costs 10x fuel costs, and many of the things that got the dry weight
down sent operations costs way up. It would be somewhat disappointing
to find out that by the time you got operations costs down that low,
you were still spending $700 a pound to put something into orbit.

The other big questionable assumption is how efficiently one can turn
propellent chemical energy into payload kinetic energy - trucks and
airplanes don't do very well here, as essentially all of their
propellant energy usage goes to what would be called drag and gravity
losses in the rocket world.

-jake

"Jeff Findley"

NASA has not seriously been working on new suit technology
for quite some time.

That's not entirely true.

From Astrobiology Magazine, 10/20/2005, [http://tinyurl.com/beycr]:

Excerpt:

"Dr. Dean Eppler is a geologist at the Johnson Space Center in Houston,
Texas. For the past eight years, Eppler has participated in field tests of
experimental spacesuits as part of the Desert RATS (Research and Technology
Studies) project. The suits are being tested to provide input to the
development of flight-ready suits for future human missions to the moon and
Mars. In this year's Desert RATS field test, Eppler donned a Mark III-suit.
His colleague Keith Splawn wore an I2-suit. Splawn is an engineer at
Delaware-based ILC Dover, the company that designed and developed both
suits. The two "suit subjects" ran through a number of scenarios: scrambling
up hills; collecting rock and soil samples; testing communications and
navigation equipment; and controlling the SCOUT rover both manually and with
voice commands and gestures."

-

From The Space Review, 8/22/2005,
[http://www.thespacereview.com/article/436/1]:

Excerpt:

"But this was not the first time that NASA had tapped their expertise. In
the early 1990s, after NASA had been given lunar marching orders by a
previous President Bush, the agency had consulted with a number of its
surviving moonwalkers about designing extra vehicular activity (EVA) systems
for the lunar surface. Their recollections were compiled in a 1993 summary
document that is currently circulating throughout NASA's Johnson Space
Center. Its lessons are still valid today."

-

Also:
http://www.spaceref.ca/news/viewpr.html?pid=18009
http://www.spaceref.com/news/viewpr.html?pid=18037
http://www.spaceref.com/news/viewpr.html?pid=18076

--
Jon

"Jon S. Berndt" jsb.at.hal-pc-dot.org wrote in message
...
"Jeff Findley"

NASA has not seriously been working on new suit technology
for quite some time.

That's not entirely true.

snip

While this research looks promising, I won't think NASA is serious until it
starts testing in LEO. You'd hope that better suits would be available by
the time NASA makes its next moon landing. The Apollo era suits were
showing a lot of wear and tear after their short usage on the Apollo lunar
EVA's. If NASA truly wants to have lunar missions up to six months, they
have a lot of work ahead of them.

When we see NASA testing a zero pre-breathe suit in LEO, I'll take notice.

Jeff
--
Remove icky phrase from email address to get a valid address.

In article , Henry Spencer says...

In article . com,
Jake McGuire wrote:
Most commercial transportation seems to come out somewhere in the
neighborhood of 7 times fuel costs. Or at least airlines and trucking
companies do...

Note, though, that magically (say) doubling the fuel capacity of an
airliner would not double its operating costs; most of them don't scale
with fuel use.

Not magically, no, but pragmatically perhaps. The more money you're
spending on fuel, the more you look for operational fixes to the fuel
problem, including expensive ones that weren't worth the cost when
fuel wasn't as big a cost. And the more you're spending on fuel,
the less important it is to cut costs elsewhere - shaving a couple
bucks off the in-flight meal prep may be worthwhile when you're trying
to sell $200 coast-to-coast tickets to the masses, less so when fuel
costs mean that market is never going to be profitable and you have
to go after a smaller number of higher-paying passengers.

Not direct consequences of increased fuel use or fuel cost, and not
immediate reactions to it. But in the long run, and especially as
new generations of equipment are designed for the new cost structure,
the tendency to focus on shortening the long pole tends to make all
the poles of similar length.


Rockets ought to have *lower* ratios than airliners, in fact much
lower, because they are so much more fuel-intensive, and fuel is
the easy part.

Which means there's little motive to cut fuel costs, and much interest
in cutting equipment or operations costs even if that means burning
more fuel, until all the poles are about the same length again.


--
*John Schilling * "Anything worth doing, *
*Member:AIAA,NRA,ACLU,SAS,LP * is worth doing for money" *
*Chief Scientist & General Partner * -13th Rule of Acquisition *
*White Elephant Research, LLC * "There is no substitute *
* for success" *
*661-951-9107 or 661-275-6795 * -58th Rule of Acquisition *

On 20 Oct 2005 10:50:04 -0700, "William Mook"
wrote, in part:

We haven't done this, which is why we didn't follow Max Faget's advice
and reuse the F1 and J2 engine sets in building a fully reusable
shuttle with an ablative sheild.

http://history.nasa.gov/SP-4221/p208.jpg

Instead we invented a new SSME and SRB combination with new thermal
tiles - since that justified higher costs and hence higher profits. We
also went from stacked stages to parallel stages which created
headaches we are still living with today (failed O-rings causing
complete destruction of the shuttle at lift-off, foam impacting thermal
tiles again causing complete destruction of the shuttle at re-entry)

This is a very good example.

I should have been more specific, I guess. I am not at all intending to
deny that there are a lot of ways to make spaceflight a little cheaper.
Or even a lot cheaper - compared to what it costs now.

What I don't believe is possible, though, at any time in the near
future, is making spaceflight *cheap*. Not until rockets can be replaced
by something else.

John Savard
http://home.ecn.ab.ca/~jsavard/index.html
http://www.quadibloc.com/index.html
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John Schilling wrote:

:In article , Pat Flannery says...
:
:Henry Spencer wrote:
:
: The fundamental cost of
:putting mass into orbit with LOX/kerosene is under $1.50/kg.
:
:Wait a minute; leaving the LOX out of the equation, I can accelerate 1
:kg of mass to 18,000 mph and 100 miles altitude with the energy in
:around 2/3rds of a gallon of Kerosene?
:
:Yes. Yes you can. Higher heating value of gasoline typically runs
:about 20,000 btu/lb, or in proper units 45 MJ/kg. Two-thirds of a
:gallon of gasoline weighs in at 1.8 kilograms. So, over eighty
:megajoules of energy to play with.
:
:Combined kinetic and potential energy of an object at 100 miles and
:18,000 mph is thirty-four megajoules per kilogram. So you only need
:to achieve an overall efficiency of 40% to pull this off. Rockets
:can do this easily.
:
:It's running around $2.75 at the moment.
:
omestic retail, including road-use tax. We'll be buying wholesale, and
:where we're going, we don't need *roads*.
:
:Price of LOX in 2001 was about $.67 per gallon.
:
:Cheaper than that if you build your own LOX extractor on-site, which is
:worth doing if you're using it in rocket-propellant quantities.

I'll simply note that everyone is ignoring the energy required to get
through all that pesky air....

--
"When you enter a room full of armed men, shoot the first
person who makes a move, hostile or otherwise. He has
started to think and is therefore dangerous..."
-- Colonel Paddy Mayne, co-founder of the SAS

John Schilling wrote:

:We've already *done* that. Some of us, are profoundly uninterested in doing
:it again, and baffled by anyone who is enthusiastic about the prospect.

Yes, but the problem is that we did it and then immediately lost the
capability to do it again.

:And beyond that, what specific things can you do, things that are actually
:worth doing, with Stick/CEV?

I can just see you now at the dawn of aviation. "But we ALREADY did
powered flight. Stop messing around with building those and build
something NEW...."

--
"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

In article ,
Jon S. Berndt jsb.at.hal-pc-dot.org wrote:
NASA has not seriously been working on new suit technology
for quite some time.

That's not entirely true.

The key word is "seriously". NASA has funded a tiny trickle of suit work
for a long time.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

In article ,
Fred J. McCall wrote:
:We've already *done* that. Some of us, are profoundly uninterested in doing
:it again, and baffled by anyone who is enthusiastic about the prospect.

Yes, but the problem is that we did it and then immediately lost the
capability to do it again.

Yes, and that happened because the program was structured to end that way.
It was not some malicious Act Of God, an inexplicable bolt out of the
blue; it was predictable. Structuring a new program the same way will
yield the same long-term result.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

In article .com,
Jake McGuire wrote:
The other big questionable assumption is how efficiently one can turn
propellent chemical energy into payload kinetic energy...

While that issue might figure in some of the postings in this thread, it's
irrelevant to mine. My calculations were based on rocket mass ratios --
the characteristic numbers for a specific engineering solution to the
problem, with well-understood (in)efficiencies -- not on assumptions about
energy efficiency independent of a particular technology. I didn't bother
computing the energy content of a kilogram of LOX/kerosene; what I care
about is that you need about 13kg of LOX/kerosene to put 1kg of dry mass
into orbit (that is, a mass ratio of 14, about right with good modern
engines after allowing for the lower gravity losses of non-LH2 rockets).
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |