SSTO to LEO, 80,000 pound payload or Bust. [was Bigelow launch vehicle mistake]

In article .com,
says...

Jeff Findley wrote:
"H2-PV NOW" wrote in message
oups.com...
There's sometimes 20 replies on a thread, not all to me, or about
something I said, or even about something I am interested in reading.
The way my newsreader strings messages together, replies might be
positioned far from the message it is a reply to.

I may get tired after reading 18 of the 20 new ones and never get to
the two others not read, and next login may have 20 more new ones to
look at. It seems Swanson is irked because you said something I didn't
respond to. Since there's no pleasing Swanson, I no longer try.

Your arguemnts are full of hand waving. You lack any math to back up your
absurd assertions.


The rocket motors need some redesign in the long run, but there are
probably several which would satisfy the 1st generation of spaceplanes
for the few years they would be needed. Just get one SSTO into orbit
and back, leaving an 80,000 pound payload at LEO, and everybody in the
rocket business will be on the project, shaving weight and boosting
thrust to get the orders to equip a fleet of 500 of them.

So the questions are premature, and you should know enough to know that
much, if you know as much as you claim to know, you, who dares call
others ignorant.


Note that NASP was cancelled because just such a vehicle is a *hard thing*
to develop and fly. This is a technology that's ready for a multi-billion
dollar research project, not a viable, off the shelf, technology to use f=
or
an operational, inexpensive, launch vehicle.

If that is your opinion than what does it say about you spending so
much time discussing it? How many hours a day do you actually spend
devoted to doomed hopeless endeavors? And Why would you do that?


As I said in the beginning, your handwaving arguments prove only that you
know very little about aerodynamics, thermodynamics, and propulsion. In
short, you show that you don't have the aerospace engineering education
and/or background to put forth a meaningful launch vehicle proposal.

Jeff

You have revealed some huge gaps in your own supposed omniscience
yourself there Bubba. You must live a totally alienated existence where
your craving for even meager scraps of attention cause you to engage
such an unworthy as myself in lengthy timewasting exercises which have
no possibility of ever bearing any fruit. I think a portrait of you is
starting to emerge, and it's not very pretty. Or as Oscar Wilde once
said when a dame called him a drunk: "I am drunk and you are ugly. In
the morning I will be sober but you will still be ugly."

Nice quote. I think it applies to your postings rather well.
I see you were up late last night. Suffering insomnia, are we?

Lets take a stab at calculating the fuel mass needed to loft a SR-71 to orbit
from the pinacle of it's flight envelope. I'm trying to compute just the
energy needed, without all the messy stuff.

Potential energy to lift 1 kg from 100,000 ft (19 miles) to LEO at 220 miles =
(220 - 19) * 1,609 m/mi * g = 3.173 *10^6 joules/kg

Kinetic energy at 1 km/s = 1/2 mv^2 = .5 * 10^6 joules/kg

Kinetic energy at 8 m/s = .5 * 64 * 10^6 joules/kg = 32 *10^6 joules/kg

Total energy to reach ISS from 100,000 ft = (3.17 + 32 - .5)*10^6 = 34.67 *10^6
joules/kg

For a 30 mt (66,000 lb) vehicle, that's 1,040 * 10^9 joules

From chemistry, combining Hydrogen + Oxygen yeilds 242 kJ per mole hydrogen
burned
or water formed. the same amount of energy is required to split water into H2
+ O2.

So, 242 kJ/18 g = 13.4 *10^6 J/kg of H2 and O2 fuel,

If the conversion is 100% efficient, the minimum amount of fuel needed is 77.6
mt LH2/LO2. That fuel must be in the tanks when the rocket is lit.

A rocket engine might be only 50% efficient, thus, the amount of LOx and LH2
required might be twice that amount, 155.2 mt, or 155,000 kg. Now, think for a
second. This calculation ignores the air drag above 100,000 ft and there is no
"payload", as the empty weight of an SR-71 is 59,000 lb. Also, some of the fuel
mass must be accelerated along the way, so the proper calculation is much more
complicated. If you actually want to leave something at LEO, the fuel mass goes
up accordingly.

Of course, none of this is new...

http://history.nasa.gov/SP-4404/app-a2.htm

Now, look at the estimates for SKYLON SSTO:

Unladen Mass: 41,000kg
Fuel Mass: 200,000kg
Maximum Payload Mass: 12,000kg

That's assuming SKYLON actually works as calculated..

--
Eric Swanson --- E-mail address: e_swanson(at)skybest.com :-)
--------------------------------------------------------------

Past his Prime Eric Swansong wrote:
In article .com,
says...

Jeff Findley wrote:
"H2-PV NOW" wrote in message
oups.com...
There's sometimes 20 replies on a thread, not all to me, or about
something I said, or even about something I am interested in reading.
The way my newsreader strings messages together, replies might be
positioned far from the message it is a reply to.

I may get tired after reading 18 of the 20 new ones and never get to
the two others not read, and next login may have 20 more new ones to
look at. It seems Swanson is irked because you said something I didn't
respond to. Since there's no pleasing Swanson, I no longer try.

Your arguemnts are full of hand waving. You lack any math to back up your
absurd assertions.


The rocket motors need some redesign in the long run, but there are
probably several which would satisfy the 1st generation of spaceplanes
for the few years they would be needed. Just get one SSTO into orbit
and back, leaving an 80,000 pound payload at LEO, and everybody in the
rocket business will be on the project, shaving weight and boosting
thrust to get the orders to equip a fleet of 500 of them.

So the questions are premature, and you should know enough to know that
much, if you know as much as you claim to know, you, who dares call
others ignorant.


Note that NASP was cancelled because just such a vehicle is a *hard thing*
to develop and fly. This is a technology that's ready for a multi-billion
dollar research project, not a viable, off the shelf, technology to use f=
or
an operational, inexpensive, launch vehicle.

If that is your opinion than what does it say about you spending so
much time discussing it? How many hours a day do you actually spend
devoted to doomed hopeless endeavors? And Why would you do that?


As I said in the beginning, your handwaving arguments prove only that you
know very little about aerodynamics, thermodynamics, and propulsion. In
short, you show that you don't have the aerospace engineering education
and/or background to put forth a meaningful launch vehicle proposal.

Jeff

You have revealed some huge gaps in your own supposed omniscience
yourself there Bubba. You must live a totally alienated existence where
your craving for even meager scraps of attention cause you to engage
such an unworthy as myself in lengthy timewasting exercises which have
no possibility of ever bearing any fruit. I think a portrait of you is
starting to emerge, and it's not very pretty. Or as Oscar Wilde once
said when a dame called him a drunk: "I am drunk and you are ugly. In
the morning I will be sober but you will still be ugly."

Nice quote. I think it applies to your postings rather well.
I see you were up late last night. Suffering insomnia, are we?

I can't sleep but you are a stinky skunk. In the morning I will sleep
late but you will stink to the day you die.

But thanks for your get well card during my convalescence after my
near-death experience hospitalization last month. Your solicitude for
my well being is only matched by your charm and personality. NOT.


Lets take a stab at calculating the fuel mass needed to loft a SR-71 to orbit
from the pinacle of it's flight envelope. I'm trying to compute just the
energy needed, without all the messy stuff.

Go ahead with the messy stuff. We're all adults here and have seen
naked physics before (well, I think the Creation Science Taliban
enforcers have all gone away after viewing the meaningless bickering,
assured that no progress will ever be made in this thread so they can
go back to NSA and spy on the democrats phone calls.)


Potential energy to lift 1 kg from 100,000 ft (19 miles) to LEO at 220 miles =
(220 - 19) * 1,609 m/mi * g = 3.173 *10^6 joules/kg

Kinetic energy at 1 km/s = 1/2 mv^2 = .5 * 10^6 joules/kg

Kinetic energy at 8 m/s = .5 * 64 * 10^6 joules/kg = 32 *10^6 joules/kg

Total energy to reach ISS from 100,000 ft = (3.17 + 32 - .5)*10^6 = 34.67 *10^6
joules/kg

For a 30 mt (66,000 lb) vehicle, that's 1,040 * 10^9 joules

=================
From chemistry, combining Hydrogen + Oxygen yeilds 242 kJ per mole hydrogen
burned
or water formed. the same amount of energy is required to split water into H2
+ O2.

This computation is inaccurate. Conventionally the LHV (Lower Heating
Value) is employed on Earth at STP, as the latent heat in the
low-temperature steam product is unusable. The HHV (Higher Heating
Value) is the stoichiometric ideal conversion of H2O - H2+O - H2O.

That does not represent the total energy in LH2/LOX, as the link you
provided explains in easy to understand lanuage:
http://history.nasa.gov/SP-4404/app-a2.htm
"... From what was known about heats of combustion by the start of the
twentieth century, it is not at all surprising that Tsiolkovskiy became
the first to propose the use of liquid hydrogen and oxygen to propel a
rocket, which he did in his classic "Exploration of the Universe with
Reaction Machines," first published in 1903 .6 Tsiolkovskly used a heat
of formation of water of 16 .106 joules per kilogram (from reacting
hydrogen and oxygen) and recognized that some heat would be expended in
[255] converting liquid hydrogen and liquid oxygen to their gaseous
states.**** He converted this heat of formation into mechanical energy
and obtained a potential energy of 1633 kilogram-meters. Using Newton's
relationship between potential and kinetic energy, Tsiolkovskiy
calculated the exhaust jet velocity of a liquid hydrogen-liquid oxygen
rocket as 5700 meters per second.***** Using this value, he calculated
vehicle velocities for a range of mass ratios. For example, at a mass
ratio Mo/ Me, of 5, vehicle velocity was 9170 meters per second.
Tsiolkovskiy preferred a mass ratio of 5, which means that 80 percent
of the vehicle mass is propellant, because he calculated this ratio
gave the greatest utilization of propellants.****** ..."

LH2/LOX embodies about 30% more total potential energy than H2+O2 at
STP.

Depending on your total exergy analysis, this can either be good or
bad, depending on the route used to final exhaust velocity.

=================

So, 242 kJ/18 g = 13.4 *10^6 J/kg of H2 and O2 fuel,

If the conversion is 100% efficient, the minimum amount of fuel needed is38.8
mt LH2/LO2. That fuel must be in the tanks when the rocket is lit.

A rocket engine might be only 50% efficient, thus, the amount of LOx and LH2
required might be twice that amount, 77.6 mt, or 155,000 kg. Now, think for a
second. This calculation ignores the air drag above 100,000 ft and thereis no
"payload", as the empty weight of an SR-71 is 59,000 lb. Also, some of the fuel
mass must be accelerated along the way, so the proper calculation is muchmore
complicated. If you actually want to leave something at LEO, the fuel mass goes
up accordingly.

As you ought to be informed, NASA uses a rich fuel ratio in the
shuttle.

Hydrogen at stoichiometric ideal conversion is 2 atomic weights of H to
16 atomic weights of O. The Hydrogen is so light weight that roctet
engines use double the H2 required for perfect ideal combustion. 4
atomic weights of H to 16 atomic weights of O, when using LH2/LOX.

The Shuttle uses Slush-LH2/LOX at a ratio of 6 atomic weights of H to
32 atomic weights of O. Wasting a higher fractional portion of the
lowest weights relative to the highest weights produces the most net
usuable thrust per total mass. Again, slush-LH2 has 16% more embodied
energy available in the optimized exergy cascade.

As Einstein noted: "Everything should be reduced to as simple as
possible, and no further." You have over-simplified to the point that
serious errors have blinded you to realities unknown to those wearing
blinders.

Again, as your own link reminds you, and you ought to know:

http://history.nasa.gov/SP-4404/app-a2.htm#b116
"... Oberth also recognized that a rocket had greater thrust when
operating outside the earth's atmosphere than within it and cited
Goddard's experiments as proof. ..."

To take the HHV and extrapolate that to all heights and atmospheric
thicknesses does not describe conditions on Earth, and cannot be useful
in designing an aerospaceplane capable of reaching LEO.

Spaceplane to LEO is rung four on the Ladder to the Planets and the
Stars. Everything which has gone before is rung zero, or rung 0.5, or
0.9. Not even Rung One yet. Rung Four is not the most urgent priority
yet. Rung Three, the Hydrogen Economy will certainly produce great
developments in Hydrogen production, storage, and utility which will be
immensely useful in final refinement of a SSTO LH2/LOX craft.
Preliminary drafts of such a craft are not premature, but the
generations of evolution will be only a few years apart.

Hydrogen tanks were the barrier to LH2/LOX spaceplanes and rockets in
the first century of development. They seemingly still are.

Optimum Utilization of Available Space in a Vehicle through Conformable
Hydrogen Vessels iiia2_aceves.pdf
http://www.eere.doe.gov/hydrogenandf...ia2_aceves.pdf

Advanced Concepts for Containment of Hydrogen and Hydrogen Storage
Materials st16_aceves.pdf
http://www.hydrogen.energy.gov/pdfs/...t16_aceves.pdf

Advanced Concepts for Containment of Hydrogen and Hydrogen Storage
Materials vi_e_2_aceves.pdf
http://www.hydrogen.energy.gov/pdfs/...e_2_aceves.pdf

Inexpensive delivery of compressed hydrogen with advanced vessel
technology pdp_54_aceves.pdf
http://www.hydrogen.energy.gov/pdfs/..._54_aceves.pdf

Inexpensive delivery of compressed hydrogen with ambient temperature or
cryogenic compatible vessels 2005 03_aceves_llnl.pdf
This file has been withdrawn by publisher

Flexibly Fueled Storage Tank Brings Hydrogen-Powered Cars Closer to
Reality 06_03.4.pdf
http://www.llnl.gov/str/June03/pdfs/06_03.4.pdf

Hydrogen Storage Using Lightweight Tanks 2003
46_llnl_andrew_weisberg.pdf
http://www.eere.energy.gov/hydrogena...w_weisberg.pdf

Vehicular Hydrogen Storage Using Lightweight Tanks 1999 235978.pdf
http://www.llnl.gov/tid/lof/documents/pdf/235978.pdf

^^^^^^^^^^^^^^^^^^^^^^^^
Now you see it, now you don't, in 1/3000th of second.
http://www.eere.energy.gov/hydrogena...eisberg_04.pdf
http://www.eere.energy.gov/hydrogena...fs/30535ar.pdf
^^^^^^^^^^^^^^^^^^^^^^^^

The last two links talk about a novel "failure mode", instantaneous
total disintergration of fiber-wrapped H2 tanks. They call it new, in
2004, but I read about the same phenomenon was known and studied in the
labs and discussed in a 1988 book:

http://snipurl.com/ne8o
http://www.amazon.com/gp/product/071...lance&n=283155
Science of Structures and Materials (Scientific American Library)
(Hardcover)
by J. E. Gordon
# Hardcover: 217 pages
# Publisher: Scientific American Library (August 1988)
# Language: English
# ISBN: 0716750228

http://www.worldcatlibraries.org/wcp...4da09e526.html
Find in a Library: The science of structures and materials
.... · Title: The science of structures and materials · Author: J E
.... Book · Subjects: Strength of materials, Structures, Materials,
Structural analysis (Engineering), Strength ...

SEE PAGES 91-94.

"... Even so, in highly stressed structures such as aircraft, the
quantity of energy stored is far from negligible. At Farnborough it is,
or used to be, the practice to test complete large aircraft to
destruction in the test frame. Such tests required a considerable
number of assistants to read the various dials and gauges. When the
structure was obviously nearing failure, the officer in charge of the
test would shout a warning and we would all run for cover. The final
failure of a large airframe can be a dramatic business once the
critical stage is passed.
Now that it is easier to achieve in the laboratory close
approximations to the theoretical strengths of many solids, we have to
face the fact that the strain energy stored in a material under a load
approaching its theoretical capacity approximates to the total chemical
bond energy. In fact, the strain energy released at fracture by these
very strong specimens is roughly the same per unit weight as that
released by a conventional chemical explosive such as dynamite.
Thus when very strong fibers and crystals are broken in devices
such as Marsh's microtesting machine, the result is quite different
from that observed when ordinary engineering test pieces are broken.
Instead of a mild bang and two broken pieces, there is an explosion
followed by a little cloud of dust or smoke. Otherwise there are no
visible remains of the test specimen, which has simply vanished. Only
the very small size of such test specimens prevents -them from doing
serious damage to both the equipment and the experimenter.
Clearly, attempts to subject materials to stresses near the
theoretical maximum in a real structure would be far too dangerous: one
might as well try to build an aircraft out of dynamite. This does not
mean that the stresses in engineering structures cannot be raised above
their present levels, but to raise them even moderately with safety
requires considerable skill and knowledge on the part of the designer.
...."


Of course this not only applies to H2-tanks, but also to the spacecraft
in its entirely.

One of the reasons for getting spaceplanes to LEO in the first place
is to make new materials in zero-G with higher failure limits and/or
greater strength to weight, and/or better thermal performance for the
second generation of spaceplanes. That first generation will have to be
replaced and retired as soon as possible for reasons known (to some at
least) since the mid-1980s.

Of course, none of this is new...

http://history.nasa.gov/SP-4404/app-a2.htm

Now, look at the estimates for SKYLON SSTO:

Unladen Mass: 41,000kg
Fuel Mass: 200,000kg
Maximum Payload Mass: 12,000kg

That's assuming SKYLON actually works as calculated..

My prediction is SKYLON will not work as predicted for reasons given at
length in recent posts above in thread and in parallel threads in the
same newsgroups.

H2-PV NOW wrote:

As you ought to be informed, NASA uses a rich fuel ratio in the
shuttle.

Hydrogen at stoichiometric ideal conversion is 2 atomic weights of H to
16 atomic weights of O. The Hydrogen is so light weight that roctet
engines use double the H2 required for perfect ideal combustion. 4
atomic weights of H to 16 atomic weights of O, when using LH2/LOX.

You have no idea what you're talking about. Rockets tend to run fuel
rich (not "rich fuel") with LOX/Hydrogen to improve the specific
impulse, and the Shuttle runs it in a 6:1 (rather than the
stoichiemetric 8:1) ratio, in order to optimize this.

The Shuttle uses Slush-LH2/LOX

The Shuttle does not use slush hydrogen. It uses liquid hydrogen.

at a ratio of 6 atomic weights of H to
32 atomic weights of O.

No. It's one hydrogen to six oxygen.

Wasting a higher fractional portion of the
lowest weights relative to the highest weights produces the most net
usuable thrust per total mass. Again, slush-LH2 has 16% more embodied
energy available in the optimized exergy cascade.

No, energy is entirely beside the point (and I have no idea what
"exergy" is, or how or why it cascades). The maximum energy is achieved
with a stoichiometric ratio.

Do you enjoy flaunting your ignorance of aerodynamics and rocketry in
front of thousands of Usenet readers?

Rand Simpleton wrote in
news
H2-PV NOW wrote:

As you ought to be informed, NASA uses a rich fuel ratio in the
shuttle.

Hydrogen at stoichiometric ideal conversion is 2 atomic weights of H to
16 atomic weights of O. The Hydrogen is so light weight that roctet
engines use double the H2 required for perfect ideal combustion. 4
atomic weights of H to 16 atomic weights of O, when using LH2/LOX.

You have no idea what you're talking about. Rockets tend to run fuel
rich (not "rich fuel") with LOX/Hydrogen to improve the specific

You are absolutely correct. Hydrogen takes great offense in being called rich fuel instead of fuel rich. I
wonder if Hydrogen will ever forgive me for my faux paux.

impulse, and the Shuttle runs it in a 6:1 (rather than the
stoichiemetric 8:1) ratio, in order to optimize this.

The Shuttle uses Slush-LH2/LOX

The Shuttle does not use slush hydrogen. It uses liquid hydrogen.

at a ratio of 6 atomic weights of H to
32 atomic weights of O.

No. It's one hydrogen to six oxygen.

And when burned makes HO6????



Wasting a higher fractional portion of the
lowest weights relative to the highest weights produces the most net
usuable thrust per total mass. Again, slush-LH2 has 16% more embodied
energy available in the optimized exergy cascade.

No, energy is entirely beside the point (and I have no idea what
"exergy" is, or how or why it cascades). The maximum energy is achieved
with a stoichiometric ratio.

In an ideal world, say, for example one without Al Qaeda or George Bush in it. In the Real World the gases
are being introduced so durned fast and the fires are exploding so turmultously that not every Oxygen meets
up with exactly two Hydrogens, so some fuel and some oxidiser would get wasted. The O2 is 16 times
heavier than the H2, so if one is going to get wasted, the lightest one is the one you use more of -- in this
case 4H2 to O2 produces the best result of expanded gases. With RICH FUEL of double the Hydrogen, the
chances of all the O2s meeting partners is doubled.

But thanks for giving us insight into how Creation Science teaches "Fizziks". I think "exergy" will be added
to Creation Science Fizziks when Moses brings down the next set of tablets.



Do I flaunting my ignorance of aerodynamics and rocketry in
front of thousands of Usenet readers?

I'm sure both usenet readers enjoy your flaunts.

H2-PV wrote:

As you ought to be informed, NASA uses a rich fuel ratio in the
shuttle.

Hydrogen at stoichiometric ideal conversion is 2 atomic weights of H to
16 atomic weights of O. The Hydrogen is so light weight that roctet
engines use double the H2 required for perfect ideal combustion. 4
atomic weights of H to 16 atomic weights of O, when using LH2/LOX.

You have no idea what you're talking about. Rockets tend to run fuel
rich (not "rich fuel") with LOX/Hydrogen to improve the specific


You are absolutely correct. Hydrogen takes great offense in being called rich fuel instead of fuel rich. I
wonder if Hydrogen will ever forgive me for my faux paux.

Hydrogen is indifferent. Readers of Usenet are not, because it's a clue
to recognizing a chemical and propulsion ignoramus.

impulse, and the Shuttle runs it in a 6:1 (rather than the
stoichiemetric 8:1) ratio, in order to optimize this.


The Shuttle uses Slush-LH2/LOX

The Shuttle does not use slush hydrogen. It uses liquid hydrogen.



What? No response?

at a ratio of 6 atomic weights of H to
32 atomic weights of O.

No. It's one hydrogen to six oxygen.


And when burned makes HO6????

No, when burned makes a combination of H2O, OH, and H molecules. It's
not an efficient combustion from an energy standpoint, but it provides
the best rocket performance for that propellant combination.

Wasting a higher fractional portion of the
lowest weights relative to the highest weights produces the most net
usuable thrust per total mass. Again, slush-LH2 has 16% more embodied
energy available in the optimized exergy cascade.

No, energy is entirely beside the point (and I have no idea what
"exergy" is, or how or why it cascades). The maximum energy is achieved
with a stoichiometric ratio.


In an ideal world, say, for example one without Al Qaeda or George Bush in it. In the Real World the gases
are being introduced so durned fast and the fires are exploding so turmultously that not every Oxygen meets
up with exactly two Hydrogens, so some fuel and some oxidiser would get wasted. The O2 is 16 times
heavier than the H2, so if one is going to get wasted, the lightest one is the one you use more of -- in this
case 4H2 to O2 produces the best result of expanded gases. With RICH FUEL of double the Hydrogen, the
chances of all the O2s meeting partners is doubled.

Thank you for once again demonstrating your complete ignorance of
chemistry and combustion physics.

But thanks for giving us insight into how Creation Science teaches "Fizziks". I think "exergy" will be added
to Creation Science Fizziks when Moses brings down the next set of tablets.

I'm an evolutionist, and an agnostic. Sorry to disappoint your
simpleton assumptions.

On Thu, 9 Mar 2006 18:19:04 GMT, (Henry Spencer)
wrote:

In article ,
beav wrote:
a two stage to orbit craft(s), using a modified XB70 (?!?!!!!) mother
ship and a smaller orbital craft, built and flown in the 1990 era out
of Groom Lake.

Correction: a *rumor* of such a craft.


god bless AWST for being real journalists based on waiting for Gov't
confirmation.

they chatted about Pave Blue years before it was declassified, leading
up to the F117 operational deployment..


the smaller orbital craft apparently used aerospikes!

Actually, the way the article is written shows that the author doesn't
really understand what an aerospike is. It's not an airbreathing engine.

i'll have to reread it. i figured the aerospikes were just for the
boost to orbit off the nominal XB70. are you talking about the
artist?

besides, during the discussion of aerospikes, The MD engineer said
that "aerospikes had history" with regard to the X33, even tho it
could've just been test cell operation...

what's interesting was there was no discernable discussion of the 1998
"aurora" sightings. rather than aerospikes, the baby craft may have
used the putative pulse jet engine that gave the donut on a rope
contrail. that'd certainly tie up two loose ends.


say!

mount up an aerospiked/pulse jet CEV on the mother ship and launch
everything else up to LEO in a big dumb booster.

SIMPLETON wrote:
H2-PV wrote:

As you ought to be informed, NASA uses a rich fuel ratio in the
shuttle.

Hydrogen at stoichiometric ideal conversion is 2 atomic weights of H to
16 atomic weights of O. The Hydrogen is so light weight that roctet
engines use double the H2 required for perfect ideal combustion. 4
atomic weights of H to 16 atomic weights of O, when using LH2/LOX.

You have no idea what you're talking about. Rockets tend to run fuel
rich (not "rich fuel") with LOX/Hydrogen to improve the specific


You are absolutely correct. Hydrogen takes great offense in being called rich fuel instead of fuel rich. I
wonder if Hydrogen will ever forgive me for my faux paux.

Hydrogen is indifferent. Readers of Usenet are not, because it's a clue
to recognizing a chemical and propulsion ignoramus.

impulse, and the Shuttle runs it in a 6:1 (rather than the
stoichiemetric 8:1) ratio, in order to optimize this.


The Shuttle uses Slush-LH2/LOX

The Shuttle does not use slush hydrogen. It uses liquid hydrogen.



What? No response?

I checked. You're right. I hadn't realized that NASA hasn't adopted
space-age concepts for fuel yet. I just ASSUMED they were using modern
fuels and techniques.


at a ratio of 6 atomic weights of H to
32 atomic weights of O.

No. It's one hydrogen to six oxygen.


And when burned makes HO6????

No, when burned makes a combination of H2O, OH, and H molecules. It's
not an efficient combustion from an energy standpoint, but it provides
the best rocket performance for that propellant combination.

Wasting a higher fractional portion of the
lowest weights relative to the highest weights produces the most net
usuable thrust per total mass. Again, slush-LH2 has 16% more embodied
energy available in the optimized exergy cascade.

No, energy is entirely beside the point (and I have no idea what
"exergy" is, or how or why it cascades). The maximum energy is achieved
with a stoichiometric ratio.


In an ideal world, say, for example one without Al Qaeda or George Bush in it. In the Real World the gases
are being introduced so durned fast and the fires are exploding so turmultously that not every Oxygen meets
up with exactly two Hydrogens, so some fuel and some oxidiser would get wasted. The O2 is 16 times
heavier than the H2, so if one is going to get wasted, the lightest one is the one you use more of -- in this
case 4H2 to O2 produces the best result of expanded gases. With RICH FUEL of double the Hydrogen, the
chances of all the O2s meeting partners is doubled.

Thank you for once again demonstrating your complete ignorance of
chemistry and combustion physics.

Your plan is to take the heavier of two components of bi-propellent,
and make sure that it is wasted at twice the rate required for ideal
combustion, and then pat yourself on the back as "smart"???

That sure sounds like something they teach in Kansas Creation Science
classes to monkey-kids who haven't evolved into intelligent beings yet.



But thanks for giving us insight into how Creation Science teaches "Fizziks". I think "exergy" will be added
to Creation Science Fizziks when Moses brings down the next set of tablets.

I'm an evolutionist, and an agnostic. Sorry to disappoint your
simpleton assumptions.

On Thu, 09 Mar 2006 21:00:59 -0800, Rand Simberg
wrote:

No. It's one hydrogen to six oxygen.
And when burned makes HO6????
No, when burned makes a combination of H2O, OH, and H molecules. It's
not an efficient combustion from an energy standpoint, but it provides
the best rocket performance for that propellant combination.

Also - that 6:1 ratio is weights, not moles. You're combining six
kilograms of oxygen with one kilogram of hydrogen. If you want to
talk molar ratios, it's still about 1:1... maybe 1.2:1 O/F. :-)

But thanks for giving us insight into how Creation Science teaches "Fizziks". I think "exergy" will be added
to Creation Science Fizziks when Moses brings down the next set of tablets.
I'm an evolutionist, and an agnostic. Sorry to disappoint your
simpleton assumptions.

Hey - maybe he mistook you for a classmate. :-) It's rather
obvious that the poor guy never passed high-school physics and
chemistry.

And before anyone gets into MY beliefs - I'm a member of the
"Insufficient Data" club. :-)

On Sat, 11 Mar 2006 09:54:03 -0500, Len Lekx
wrote:

Also - that 6:1 ratio is weights, not moles. You're combining six
kilograms of oxygen with one kilogram of hydrogen. If you want to
talk molar ratios, it's still about 1:1... maybe 1.2:1 O/F. :-)

Whoops - got it backwards. That should be - 1:1.2 O/F - in order
to be fuel-rich.

Len Lekx wrote:
On Thu, 09 Mar 2006 21:00:59 -0800, Rand Simberg
wrote:

No. It's one hydrogen to six oxygen.
And when burned makes HO6????
No, when burned makes a combination of H2O, OH, and H molecules. It's
not an efficient combustion from an energy standpoint, but it provides
the best rocket performance for that propellant combination.

Also - that 6:1 ratio is weights, not moles. You're combining six
kilograms of oxygen with one kilogram of hydrogen. If you want to
talk molar ratios, it's still about 1:1... maybe 1.2:1 O/F. :-)

No I don't want to talk moles. I want to talk MASS. The heaviest stuff
gets used the heaviest and cannot be wasted -- the lightest stuff costs
the least fuel to lift and therefore can be wasted more than the heavy
stuff.

That's why ATOMIC WEIGHTS are part of the element's data tables, as
well as density, as well as specific weight, as well as specific
impulse. Moles are not there simply because moles are nothing more than
an Avogadro's number of the counts of the element. Knowing nothing more
than an element name and the number of atoms in a mole of an element
means you know nothing useful about that element so far.

http://en.wikipedia.org/wiki/Space_S..._External_Tank
http://en.wikipedia.org/wiki/Image:S...ternaltank.jpg
The Shuttle ET tank has 1,361,936 pounds of LOX maximum, 227,641 pounds
of LH2.

That is 6 times the WEIGHT of Oxygen to 1 part Hydrogen WEIGHT.

The burned Hydrogen-Oxygen ratios (H2O) are 2 parts H weight to 16
parts O weight. In short, the LOX is not available to burn 6 oxygen
atoms per one hydrogen atom as stated by the parent poster.

Anybody careless about knowledge of weights does not step foot on
spaceplanes. Period. Ever.

In terms of atoms ratios: 85,121 units of Oxygen (1,361,936 divided by
atomic weight 16) to 113,820.5 units of Hydrogen (227,641 divided by 2
for H2) shows there is a ratio of 1:1.337 O to H2, or one third more
hydrogen than the amount required for ideal perfect combustion.




But thanks for giving us insight into how Creation Science teaches "Fizziks". I think "exergy" will be added
to Creation Science Fizziks when Moses brings down the next set of tablets.
I'm an evolutionist, and an agnostic. Sorry to disappoint your
simpleton assumptions.

Hey - maybe he mistook you for a classmate. :-) It's rather
obvious that the poor guy never passed high-school physics and
chemistry.

And before anyone gets into MY beliefs - I'm a member of the
"Insufficient Data" club. :-)