...It only takes building 4 Space Solar Power satellites per year to.....
Jonathan
....handle the annual growth in US electrical demand. 5GW each.
According to the paper below.
Space-Based Solar Power
An opportunity for Strategic Security
2005 survey - National Space Goals
(Matula & Loveland)
4% Build a base on the Moon
6% Space Tourism
7% Search for life on other planets
7% Build a colony in space
10% Send humans to Mars
17% Deflect asteroids et
35% Solar Power Satellites
Uncle Al
>
> ....handle the annual growth in US electrical demand. 5GW each.
> According to the paper below.
Your profound broad ignorance is amusing. China installs an
additional GW of coal-fired electrical generating capacity, on
average, every week. It doesn't cost them $1 trillion/plant, either.
Where ya gonna orbit them, git? 23,500 miles out is insanely stooopid
for a vast number of reasons, and geosychronous orbital slots are
severely rationed. Near Earth orbit won't afford station-keeping.
Square miles of flimsy surface are a sail, git, solar wind and light
pressure.
What ya gonna do for construction labor? Are ya gonna have 1000
people trained for years to turn a screw? That is the training the
Hubble upgrade required, and it was still a Chinese fire drill. What
resources will be require to keep them alive in orbit? Are they gonna
bathe? Are ya gonna have high orbit whores to keep them amused? WILL
THERE BE MICRO-GEE TOILETS or the usual asstronaught adult diapers?
Are ya gonna boost the collected sewage into high orbit for future
generations or return it to Mother Earth? The Shire of Esperance will
whack your pee-pee for doing the latter.
Are ya gonna have construction Blacks, Browns, women, cripples, and
retards as per US Federal hiring requirements?
What ya gonna charge/kW-hr to make a profit, git? Might as well
tesselate the American southwest desert and declare open season on
Enviro-whiners. Oh yeah... solar cells are black and exceed 140 F
equilibrium temp in full summer sun. What would 100 mi^2 of that do
re atmospheric convection?
Where ya gonna get all those square miles of solar cells, git? How
many mi^2 of mere plastic wrap are produced annually? Solar cells
generate low voltage DC amperage. Lots and lots of amps. Are ya
gonna mine the asteroid belt for copper cabling or hollow the Earth
for millions of semiconductor inverters?
And what about the transparent surface electrode? Where ya gonna get
enough indium for ITO? Flat screen displays have skyrocketed the cost
of indium. A 32 in^2 LCD TV has $1.00 of ITO coating. 1 mi^2 =
4,014,489,600 in^2. The 200 nm-thick transparent top electrode on 1
mi^2 of solar cells will cost $125 million all by itself - if there
were that much ITO to be had.
> 2005 survey - National Space Goals
> (Matula & Loveland)
>
> 4% Build a base on the Moon
> 6% Space Tourism
> 7% Search for life on other planets
> 7% Build a colony in space
> 10% Send humans to Mars
> 17% Deflect asteroids et
>
> 35% Solar Power Satellites
People are stooopid - Washington depends upon it and has the
Department of Education to enforce it. Here's a hint, git: the Ares
heavy lifter maiden flight was a planet-class disaster. It
*demonstrated* has no ability to inject a payload into orbit.
More studies are needed. Yeah, lots more studies. Uncle Al hears
climatologists are available to rationalise the Orbital Electrical
Energy Tax on Everything. OEETE for the masses!
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm
William Mook
infrastructure. Making a light-weight system on Earth and launching
it is preferred.
A vehicle built around a modified External Tank holding hydrogen and
oxygen is the easiest way to go.
Take the Space Shuttle External Tank. It masses 26.5 metric tons
empty and 760.0 metric tons filled. Equipped with a 19.6 foot
diameter propulsive end cap made of a MEMs based propulsive skin that
weighed 1 ton and produced 1,080 tons thrust, the revised tank would
lift off with 1.4 gees.
http://www.me.berkeley.edu/mrcl/rockets.html
http://adsabs.harvard.edu/abs/2005JSAST..46...47T
http://pdf.aiaa.org/preview/CDReadyMJPC2005_1177/PV2005_3650.pdf
A thermal protection system adds 7.9 tons to
the overall mass. This brings the total to 768.9 metric tons for a
revised launcher that is fully reusable and lofts 78.1 metric tons
into LEO - located in an extended inter-tank region made to house the
payload pod.
This is enough to launch a dozen satellites into a polar orbit which
then navigate to different positions within the same orbital plane.
Two launches per orbital plane populate each plane with 24
satellites. 72 launches into 36 orbital planes populates the entire
sky with a network of satellites that turn the world into an orbital
hotspot - earning hundreds of billions of dollars per year in
communications internet banking and mediation services. It also puts
the company into a position to begin offering tele-robotic and virtual
reality services real time around the planet.
http://www.youtube.com/watch?v=I81ogcX3ONY
To launch powersats requires a larger vehicle.
Six ETs modified in a similar way, operate as a two stage to orbit
vehicle treating a centrally situated seventh ET as a cargo only
system. Looking down from above the tanks are situated as follows;
(1)(2)
(3)(4)(5)
(6)(7)
1 and 6 feed 3
2 and 7 feed 5
So, 1,2,6,7 drain as the first stage
3 and 5 are the second stage after the first 4 fall away.
The central ET is ALL payload. It carries a total of 575 metric
tons. 500 tons of that is useful, the rest is the ET and associated
hardware!
If the central ET is the system described at first, with the 78.1
metric tons payload in the interank region, the first 2 stages add 7.8
km per sec to the speed while the third stage now is capable of adding
9.2 km per second more!! With air drag and gravity losses, this is
still enough to send the 78.1 metric ton payload to the moon or
mars.
The Solar Power Satellite consists of a two thin films. One
transparent, one reflective - several kilometers in diameter. 0.1
square kilometers per metric ton! 25 square kilometers overall for a
250 ton payload. That's 5.6 kilometers in diameter when deployed
(half the payload at LEO makes it to GEO)
A 50 square kilometer system might be considered per launch (two
systems) if a method of solar navigation of the large film is worked
out from LEO to GEO.
This intercepts 34.5 GW of raw solar energy of which 14.0 GW is
available after beaming by laser energy to the ground.
http://www.youtube.com/watch?v=iWiXDu64c0g
http://www.youtube.com/watch?v=mzXwctPXT4c
http://www.youtube.com/watch?v=2QAUkt2VPHI
This is an add-on to make terrestrial solar panels more efficient. A
50 square kilometer solar panel array used to provide hydrogen for a
100,000 b/d coal to liquid plant using the Bergius process to make
16,000 tons of coal and 2,000 tons of hydrogen into gasoline, has its
hydrogen output increased 15x with the addition of a single powersat
similar to that described here - to 30,000 tons of hydrogen. Doubling
the gasoline output and using the remaining 25,000 tons of hydrogen
directly as fuel (after subtracting 1,000 tons of hydrogen to compress
and liquefy the remaining hydrogen) We have added;
100,000 barrels per day liquid fuels @ $80/bbl = $8,000,000/day
25,000 tons x 20 barrel equivalent/ton = 500,000 bpd H2
@$80/bbl = $40,000,000
So, adding $48 million per day to an existing operation's revenue
stream adds $360 billion to the value of the operation!
This is more than enough to pay for the program!!
And expand the laser beaming apparatus to support laser propelled
vehicles for mass aerial transit on Earth, and mass space travel
http://www.youtube.com/watch?v=XxV2FCUESh0
http://www.youtube.com/watch?v=nzG4PEureFg
This also allows us to contemplate developing the asteroid belt, which
brings large quantities of rich materials to Earth orbit which are
then processed telerobotically (recall the step above) into assets
that are used in space and on Earth very cheaply.
http://www.youtube.com/watch?v=FMefZhA7ifI
http://www.youtube.com/watch?v=dP5DX2NSl7c
To create a world of eight billion millionaires
http://www.youtube.com/watch?v=IcbXSONtBdY
http://www.youtube.com/watch?v=3E2586kx_Uc
While reducing environmental impact to nothing!
William Mook
> Jonathan wrote:
>
> > ....handle the annual growth in US electrical demand. 5GW each.
> > According to the paper below.
>
> Your profound broad ignorance is amusing.
Yours too.
> China installs an
> additional GW of coal-fired electrical generating capacity, on
> average, every week. It doesn't cost them $1 trillion/plant, either.
http://www.eia.doe.gov/emeu/cabs/China/Electricity.html
While the Christian Science Monitor and other conservative outlets
have made such overstatements about Chinese demand for power, actual
data from the DOE EIA show such statements are wrong.
In fact China has 624 GW of installed capacity for its 1,325 million
while the USA has 1,087 GW of installed capacity for its 300
million. In fact, most analysts believe there will be an oversupply
as the speculative bubble about Chinese growth bursts.
> Where ya gonna orbit them, git?
Geosynchronous Orbit.
> 23,500 miles out is insanely stooopid
> for a vast number of reasons, and geosychronous orbital slots are
> severely rationed.
What is your reasoning for thinking this is a show-stopper Al?
Clearly there are none. With a semi-major axis of 26,199 miles the
circumference of a circular orbit is 164,613 miles. A five mile
separation (see my other posting) would allow over 32,000 satellites
to share the same circular orbit. At 14 GW per satellite only 1,200
are needed to meet today's energy needs, and 30,000 would meet the
demands of 8 billion millionaires each flying a fleet of automated
ballistic vehicles - turning the Earth into a global village of
immense wealth.
> Near Earth orbit won't afford station-keeping.
Why?
> Square miles of flimsy surface are a sail, git, solar wind and light
> pressure.
So? Echo II was orbited in 1959 and it worked just fine. Why is any
more than a flimsy surface needed as long as its optically stable?
http://repairstemcell.files.wordpress.com/2009/02/soap-bubble.jpg
> What ya gonna do for construction labor?
Keep it on the ground at first. Then, using telerobotics, expand into
LEO, using asteroidal feedstock.
> Are ya gonna have 1000
> people trained for years to turn a screw?
WHy is that needed Al? You're making dismissive statements without
really supporting them. That makes you look 'stoopid' - lol.
> That is the training the
> Hubble upgrade required,
The Hubble only required a few folks on orbit, not 1,000.
> and it was still a Chinese fire drill.
It worked, and it used different technology than an orbiting power
station would use.
> What
> resources will be require to keep them alive in orbit?
With telerobotics, none.
> Are they gonna
> bathe?
These problems have been worked out in great detail over the past 50
years. Where have you been?
lol.
> Are ya gonna have high orbit whores to keep them amused? WILL
> THERE BE MICRO-GEE TOILETS or the usual asstronaught adult diapers?
<shrug> We've been travelling in space for over 50 years - people
have orbited the Earth and landed on the moon. You talk like this
hasn't happened, meanwhile, you assume lots of people are needed on
orbit to make things work. You have provided absolutely no support of
any of these 'stoopid' observations Al.
> Are ya gonna boost the collected sewage into high orbit for future
> generations or return it to Mother Earth? The Shire of Esperance will
> whack your pee-pee for doing the latter.
You are being silly. Raw materials returned from the asteroids,
including water ice and carbonaceous chondrites will be processed on
orbit telerobotically, and rain down plenty to everyone on Earth -
AFTER the powersats are built obviously.
> Are ya gonna have construction Blacks, Browns, women, cripples, and
> retards as per US Federal hiring requirements?
A 60 pound 90 year old woman of color will kick your ass -
telerobotically - for being such a pious racist ass.
> What ya gonna charge/kW-hr to make a profit, git?
1/10th cent per kWh.
> Might as well
> tesselate the American southwest desert and declare open season on
> Enviro-whiners.
You are a clueless ass.
> Oh yeah... solar cells are black and exceed 140 F
> equilibrium temp in full summer sun. What would 100 mi^2 of that do
> re atmospheric convection?
Depends on their efficiency dude.
> Where ya gonna get all those square miles of solar cells, git?
A square kilometer of thin film PET fabricated into a GBO reflective
film masses less than 10 tons. So, each satellite masses less than
500 tons - and fewer than 1000 are needed. That's 500,000 tons -
lasting 50 years - that's 10,000 tons per year - humanity uses
MILLIONS of tons of PET plastic.
Clueless you are Al, and no doubt clueless you will remain.
> How
> many mi^2 of mere plastic wrap are produced annually?
Lots more than needed to collect sunlight efficiently.
> Solar cells
> generate low voltage DC amperage.
Depends on how they're constructed. A multi-channel cell produces
high volts at high amperage when illuminated with intense sunlight
http://www.scribd.com/doc/20024019/White-Paper-to-Mok-FINAL-1
> Lots and lots of amps. Are ya
> gonna mine the asteroid belt for copper cabling or hollow the Earth
> for millions of semiconductor inverters?
No, you're going to make hydrogen from water and use the hydrogen to
make coal into gasoline using the Bergius process. Then, you're going
to burn hydrogen directly once its made cheaply enough.
http://www.scribd.com/doc/20023580/Testimony-Ohio-House-of-Representatives-in-Support-of-SB-221
> And what about the transparent surface electrode? Where ya gonna get
> enough indium for ITO? Flat screen displays have skyrocketed the cost
> of indium. A 32 in^2 LCD TV has $1.00 of ITO coating. 1 mi^2 =
> 4,014,489,600 in^2. The 200 nm-thick transparent top electrode on 1
> mi^2 of solar cells will cost $125 million all by itself - if there
> were that much ITO to be had.
You use CPV and appropriate PV technology.
> > 2005 survey - National Space Goals
> > (Matula & Loveland)
>
> > 4% Build a base on the Moon
> > 6% Space Tourism
> > 7% Search for life on other planets
> > 7% Build a colony in space
> > 10% Send humans to Mars
> > 17% Deflect asteroids et
>
> > 35% Solar Power Satellites
>
> People are stooopid -
You're proof of that Al.
> Washington depends upon it and has the
> Department of Education to enforce it.
And you are paranoid as well.
> Here's a hint, git: the Ares
> heavy lifter maiden flight was a planet-class disaster. It
> *demonstrated* has no ability to inject a payload into orbit.
Milton Friedman talks about this sort of ability loss over time for
all government agencies. The major catastrophe is our inability to
control military spending.
http://www.youtube.com/watch?v=xCJl-ZbHOYc
http://www.youtube.com/watch?v=ZYuK0iJqpNA
> More studies are needed. Yeah, lots more studies. Uncle Al hears
> climatologists are available to rationalise the Orbital Electrical
> Energy Tax on Everything. OEETE for the masses!
>
> --
> Uncle Alhttp://www.mazepath.com/uncleal/
> (Toxic URL! Unsafe for children and most mammals)http://www.mazepath.com/uncleal/qz4.htm
Industrial growth is built upon energy costs that are low, and through
technical innovation get less expensive every year. From 1850 to 1950
we invested in energy growth. In 1950 the oil companies realized they
had a depleting reserve. Visionaries looked toward nuclear power.
The oil companies worked with legitimate military concerns to create a
special niche for themselves. High temp nukes wouldn't be built as
Leo Strauss envisioned, so, from 1950 to 1970 oil prices stayed
relatively constant. After 1970 they began to rise, and have risen
ever since. As a result, all of the rosy scenarios of the 1950s
failed to materialize (unless you happen to be born in UAE)
This must change, technology is the change agent. Low cost reusable
launchers, combined with lightweight concentrators and efficient PV
and free electron lasers on orbit, combined with CPV systems on Earth,
have a chance at lowering the cost of energy. As energy use grows the
following development arc occurs;
1) terrestrial CPV - Gigawatt scale
2) earth orbiting SPS - terawatt scale
3) sun orbiting SPS - exawatt scale
This should have occurred over the last 50 years - it will occur over
the next 50 years - or not at all as we abandon technology altogether.
Androcles
"William Mook" <mokme...@gmail.com> wrote in message
news:7f437489-81ab-4cd8...@p23g2000vbl.googlegroups.com...
> The satellites have to be launched. This requires a launching
> infrastructure. Making a light-weight system on Earth and launching
> it is preferred.
>
> A vehicle built around a modified External Tank holding hydrogen and
> oxygen is the easiest way to go.
>
Being scrapped, a return to conventional multi-stage rockets is planned.
> Take the Space Shuttle External Tank. It masses 26.5 metric tons
> empty and 760.0 metric tons filled. Equipped with a 19.6 foot
> diameter propulsive end cap made of a MEMs based propulsive skin that
> weighed 1 ton and produced 1,080 tons thrust, the revised tank would
> lift off with 1.4 gees.
It blew up Challenger.
Sylvia Else
Only because someone applied a blow-torch to it in flight.
Sylvia.
Androcles
"Sylvia Else" <syl...@not.at.this.address> wrote in message
news:0087aa77$0$16905$c3e...@news.astraweb.com...
Shit happens and then you die. The re-entry reusable shuttle
has been scrapped - get used to it. In any case it needed two
solid rocket boosters to lift the tank, whereas three would
have lifted the shuttle without the tank and without using
its own engines - which have to be stripped down and refitted
after each flight, making a joke of reusable versus disposable.
As for re-entry, Spaceship One managed it without tiles and won
the X-prize.
http://www.scaled.com/projects/tierone/041004_spaceshipone_x-prize_flight_2.html
The whole shuttle farce was a typical American government
over-engineered mess. It's what happens when the funds are
unlimited, politicians have a say in the design and there is no
competition.
If two or three private companies has been funded instead there
would still have been accidents, I have no doubt of that, but human
space flight would be far more advanced today. As for launching
unmanned satellites, that IS competitive - and so successful that
nobody bothers to talk about it anymore, it's now old hat and the
sky is full of space junk, all of which had to be launched.
http://www.youtube.com/watch?v=Zt0AVTkDob4
Jonathan
> ... turning the Earth into a global village of
> immense wealth.
Reminds me of an old quote I like...
" Some painters transform the sun into a yellow spot, others
transform a yellow spot into the sun."
Pablo Picasso
Androcles
"Jonathan" <Ho...@Again.net> wrote in message
news:1pidnUtwm4x85LTW...@giganews.com...
Wealth is relative. The man with a car, TV, refrigerator, carpet,
warm (or cool in summer) home, computer, a full larder and
a fine wardrobe is far wealthier than the villager who hunts bison
for food and lives in a tepee, yet he complains because he has
no personal jet plane or yacht. I'm quite happy that I have that
much wealth and I no longer have to go out and fill the coal
scuttle when its snowing, as I did as a child.
William Mook
> "William Mook" <mokmedi...@gmail.com> wrote in message
>
> news:7f437489-81ab-4cd8...@p23g2000vbl.googlegroups.com...
>
> > The satellites have to be launched. This requires a launching
> > infrastructure. Making a light-weight system on Earth and launching
> > it is preferred.
>
> > A vehicle built around a modified External Tank holding hydrogen and
> > oxygen is the easiest way to go.
>
> Being scrapped, a return to conventional multi-stage rockets is planned.
So, the external tank is part of the space shuttle, which is a multi-
stage rocket. Modifying the ET is still the easiest way to go.
> > Take the Space Shuttle External Tank. It masses 26.5 metric tons
> > empty and 760.0 metric tons filled. Equipped with a 19.6 foot
> > diameter propulsive end cap made of a MEMs based propulsive skin that
> > weighed 1 ton and produced 1,080 tons thrust, the revised tank would
> > lift off with 1.4 gees.
>
> It blew up Challenger.
It wasn't the cause. A leaky seal in a section on the SRB cut through
a support strut which caused the SRB to come loose and rupture the
ET. The ET is a fabulous piece of engineering. Your statement is
disinformation designed to leave someone with the wrong impression.
William Mook
> "Jonathan" <H...@Again.net> wrote in message
>
> news:1pidnUtwm4x85LTW...@giganews.com...
>
>
>
>
>
>
>
> > "William Mook" <mokmedi...@gmail.com> wrote in message
> >news:5540751a-ae7d-4478...@g25g2000vbl.googlegroups.com...
>
> >> ... turning the Earth into a global village of
> >> immense wealth.
>
> > Reminds me of an old quote I like...
>
> > " Some painters transform the sun into a yellow spot, others
> > transform a yellow spot into the sun."
>
> > Pablo Picasso
>
> Wealth is relative. The man with a car, TV, refrigerator, carpet,
> warm (or cool in summer) home, computer, a full larder and
> a fine wardrobe is far wealthier than the villager who hunts bison
> for food and lives in a tepee, yet he complains because he has
> no personal jet plane or yacht. I'm quite happy that I have that
> much wealth and I no longer have to go out and fill the coal
> scuttle when its snowing, as I did as a child.
There is a definite relationship between the cost of energy and raw
materials and the material wealth of a people in an industrial
society. From 1850 to 1950 the cost of energy declined at an average
rate of 5% per year. As a result, industry expanded exponentially.
From 1950 through 1970, after energy companies realized they were
developing a depleting resource, the cost of energy remained
relatively constant. From 1970 through today after the first major
oil peak occurred on schedule in the USA energy prices have risen an
average of 8% per year, with a gradual erosion of living standard,
despite radical advances in automation. All attempts to end our
reliance on depleting resources have been blocked by those who know
the value of their companies will be adversely impacted by a return to
exponential declines in energy and other commodity prices going
forward.
King Hubbert, the man who first computed the logistic production curve
for oil and natural gas for the world was marginalized. Lousi Straus
who in response to concerns about what the USA would do about energy
in the 1970s which were raised by Hubbert in the 1950s said, "That by
1970 energy would be too cheap to meter" Forbes put Nuclear Energy on
the cover of the magazine, and Wall Street discovered nuclear power.
Westinghouse and GE started commercial nuclear businesses. Straus
said that low cost would be assured for nuclear because of the
development of high-temperature nuclear reactors. He was fired that
year. In 1963 JFK ordered Boorkhaven National Labs to develop an
integrated strategy to convert our industry to nuclear power. They
came up with a high-temperature nuclear reactor that would decompose
water by direct thermolysis. This hydrogen would first be used to
replace coal in coal fired power plants and the stranded coal would be
combined directly with more hydrogen to make gasoline. Later as
technology developed hydrogen fueled vehicles and machinery would be
developed. JFK was shot and killed by an assassin in Nov 1963. LBJ a
Texas oil man, ignored the Brookhaven Study. Nixon during the first
energy crisis in 1970 turned energy over to a panel of energy experts,
all from the major oil companies. Their suggested developing oil
reserves in the Middle East and improving relations in that area.
Jimmy Carter a nuclear engineer elected in the throes of an energy
induced stagflation vowed to do something about energy. He dusted off
the Brookhaven study and submitted a comprehensive plan to Congress.
That very week Karen Silkwood heirs obtained a judgement for $50
million in a wrongful death suit (later reduced to $5,000) which
created a concern about nuclear safety. At the same time Three Mile
Island in Hershey Pennsylvania melted down, exacerbating the problem.
Finally at the end of the week Hollywood released THE CHINA SYNDROME
starring Jane Fonda (who had been arrested on a marijuna charge
returning from Canada before agreeing to the film - after agreeing to
it - charges were dropped) Congress spent more than twice what was
spent on going to the moon on energy - NONE of it was to build high-
temperature nuclear reactors. In the end, alternatives to
conventional fuels were considered by most ineffective, proven by the
massive investment made during the Carter Administration. Carter shut
down the ROVER and NERVA nuclear rocket programs - the last remaining
open research on high temperature nuclear reactors - and a mechanism
to transfer technology from weapons programs to commercial nuclear
programs started by JFK. Reagan discovered 'rogue states' and refused
to trade with them. ALL rogue states were oil rich kingdoms. Secret
government documents revealed that this was a means to put half the
proved oil reserves in storage lowering depletion rates. Meanwhile he
reorganized the banking system to export the costs involved and
planned regime change when production peaked in the remaining oil rich
states. The Reagan Doctrine created the Terror threat we now face,
and his banking changes killed George Bailey style S&Ls while
enriching Mr. Potter's commercial bank - turning America into
Potterville, and most of the world into Beruit.
Perhaps you never lived in a period of real fundamental growth?
Perhaps you are too used to living in a culture in decline? In any
event, you fail to understand the natural impulse toward life
exploration and development of our global frontiers represent.
Definitely, if you are like most people alive today, you barely
understand the relationship between energy and power, the relationship
between mass flow rates between worlds, and power, and the cost of
energy. For sure like most people you do not understand at all that
ballistic transport - tossing things - the most energy efficient way
to transport a thing from point A to point B - and that rocket or jet
action is far simpler than wheels rails or wings.
We have the means, and for the past 50 years have had the means, to do
whatever the hell we wanted in the solar system. The riches of many
worlds and the energy of the sun await our developing them. The
technical means have been hidden from us in the mistaken notion that
we are more secure as a species keeping these means secret.
Meanwhile, our society rots as our people stagnate while ignorance
grows greater and greater every day.
This world can support 8 billion millionaires each with a fleet of
automated ballistic aircraft capable of travelling anywhere in minutes
and even travelling into space. This level of wealth is support by a
ring of solar power satellites beaming energy to a smaller ring of
factory satellites operated by remote control. These satellites
process imported asteroidal fragments into all manner of food and
products. These are then deorbited directly to end users anywhere on
Earth or in space
To import 16 billion tons of raw materials from the asteroid belt each
year requires that energy be expended at a rate of 6 trillion watts
continuously. Collected by solar collectors in the asteroid belt
requires a panel totalling 60,000 sq km im area.
Androcles
==================================================
Three steerable re-usable SRBs producing 12.5 million newtons, EACH,
of thrust would lift the shuttle to orbit without its 26.5 tonne tank, 760
tonnes filled, or using its own engines. As it is two are used per
launch to lift the main mass of the tank, which are committed to
launch once lit anyway - there is no safety factor.
The ET is a piss poor piece of over-engineering, the explosion of
which CAUSED the destruction of Challenger as a leak in the SRB
would not have ignited a non-existent tank. The only advantage to
liquid fuel over solid is the ability to vary the burn rate.
Your statement is bullshit designed to leave someone with your
biased and prejudiced wrong impression.
Androcles
===========================================
--- and still be no happier.
Definitely, if you are like most people alive today, you barely
understand the relationship between happiness and contentment.
Sylvia Else
Which was an entirely different ball game. It didn't go into orbit, and
never had to do a hypersonic reentry.
>
> The whole shuttle farce was a typical American government
> over-engineered mess. It's what happens when the funds are
> unlimited,
The solid-fuel boosters were used exactly because funds were limited,
and the originally proposed aircraft style reusable first stage had to
be scrapped.
Sylvia.
Androcles
"Sylvia Else" <syl...@not.at.this.address> wrote in message
You mean they were glued on as an afterthought when it was realised
the tank had weight and the tank was bolted on as an afterthought
when it was realised the shuttle wasn't big enough to carry its own
fuel. It's built like a Harley-Davidson, bits sticking out all over the
place. Call that a design? I call it a farce.
Three SRBs can lift the vehicle to orbit without the tank and a fourth
used to halt forward motion to fall and re-enter. All the vehicle really
needs are tug boat steering thrusters.
How to design a launch vehicle on a limited budget:
http://tinyurl.com/ye5mvub
You can clearly see the steering thrusters differ from the lift thrusters
in this design:
http://cache.gizmodo.com/assets/images/4/2009/05/Soyuz_Launch_Vehicle.jpg
Sylvia Else
Did you read what I wrote about the reusable first stage? It doesn't
appear that you did.
Sylvia.
Androcles
"Sylvia Else" <syl...@not.at.this.address> wrote in message
No, I knee-jerk interrupted and snipped it instead, a stupid stunt I
learnt from you.
Me
> Three SRBs can lift the vehicle to orbit without the tank
No, they can't. They would burn out at 2 minutes into the flight with
the orbiter still in the atmosphere and 1000's mph short of orbital
velocity. The SSME's using propellant from the ET provide most of the
velocity.
The SSME and ET provide approx 588M pounds sec of total impulse. One
SRB only provide 336M pounds sec of total impulse, not enough. And
the burn is too short
William Mook
Andy, are you *stealing* my writings? tsk tsk tsk...
William Mook
No it wouldn't. The shuttle as configured attains 9.2 km/sec. This
is enough to attain a 7.8 km/sec actual orbital speed with air drag
and gravity drag losses (it takes energy to fight air drag and lift
things hundreds of miles straight up)
Use the rocket equation to figure out the approximate performance of
your configuration;
Shuttle SRB.
Gross Mass: 589,670 kg (1,299,990 lb).
Empty Mass: 86,183 kg (190,000 lb).
Thrust (vac): 11,519.999 kN (2,589,799 lbf).
Isp: 269 sec.
Burn time: 124 sec.
Propellants: Solid.
Isp(sl): 237 sec.
Diameter: 3.71 m (12.17 ft).
Span: 5.10 m (16.70 ft).
Length: 38.47 m (126.21 ft).
Country: USA.
No Engines: 1.
Motor: SRB.
Cost $ : 23.2 million.
First Flight: 1981.
Last Flight: 2003.
No Launched: 232.
Other designations: Solid Rocket Booster.
760
So, this is enough to apply the rocket equation to figure its
performance.
The full mass is 589,670 kg
The empty mass is 86,183 kg
The specific impulse is 269 sec
The thrust is 11.52 mega-newtons
Alright, the the space shuttle mass is;
Stage2: 1 x Shuttle Orbiter. Gross Mass: 99,318 kg (218,958 lb). Empty
Mass: 99,117 kg (218,515 lb). Motor: 3 x SSME. Thrust (vac): 6,834.303
kN (1,536,412 lbf). Isp: 455 sec. Burn time: 480 sec. Length: 37.24 m
(122.17 ft). Diameter: 4.90 m (16.00 ft). Propellants: Lox/LH2.
The important point here is that excepting for minor fuel used for
orbital maneuvering, NO MAJOR FUEL IS CARRIED ABOARD THE ORBITER.
So, lets say 99,318 kg is the mass of the orbiter.
So, you said three SRBs would loft an orbiter into space, which means
attaining 9.2 km/sec ideally, which is reduced by air and gravity
drags which we assume is the same.
Well, lets figure it out.
Total thrust is;
11.52 MN x 3 = 34.56 MN
Total mass at lift off is;
1,868,328
So, total gee force at lift off is
34.56/9.802/1,858,328 = 1.89 gees at lift off!
Total mass at burn-out is;
357,867 kg
Total gee force at burn-out is; 9.85 gees at burn-out
That's enough to tear things apart and WAAY to much. This reduces
gravity drag, but increases air drag. An ideal solution would require
a calculus of variation, but would not be too different from the 1.7
km/sec loss suffered by the present shuttle during operation on Earth.
The important point is the speed attained doing what you suggest Andy
The specific impulse is no more than 267 seconds.
Multiply this by 9.802 m/s/s to obtain 2.62 kps exhaust speed.
The mass ratio of the full to empty weight is 5.22 when configured as
you suggest.
So, the final velocity of the empty vehicle is
Vf = Ve*LN(MR) = 2.62*LN(5.22) = 4.33 kps
Which is LESS THAN HALF the speed attained with the hydrogen tank.
The hydrogen tank provides the BULK of the delta vee capability. The
SRBs are used to lift the tank off the pad and get it to an altitude
where the SSMEs can do their work most efficiently.
> tonnes filled, or using its own engines.
Well, the SSMEs each produce 2.73 MN so three of them produce enough
thrust to generate 11 gees!!! So, this is certainly doable - BUT THE
ORBITER CONTAINS ZERO FUEL!! (except for OMS fuel which is piddling)
*thats why the External Tank is needed!!!*
SSME. Propellants: Lox/LH2. Thrust(vac): 3,728.700 kN (838,245 lbf).
Thrust(sl): 3,167.400 kN (712,060 lbf). Isp: 485 sec. Isp (sea level):
412 sec. Burn time: 500 sec. Mass Engine: 2,973 kg (6,554 lb).
Chambers: 1. Area Ratio: 600.00. Thrust to Weight Ratio: 127.89.
Country: USA. Status: Study 1978.
> As it is two are used per
> launch to lift the main mass of the tank,
Yes, reducing the need for costly SSMEs. Actually in the development
of the space shuttle, the SRBs were argued against due to their low
performance. The SRBs cannot attain orbit by themselves! So, they
certainly cannot attain orbit lifting something in addition to
themselves! lol.
> which are committed to
> launch once lit anyway - there is no safety factor.
Except when a seal leaks, or the entire charge blows up.
> The ET is a piss poor piece of over-engineering,
No its not.
> the explosion of
> which CAUSED the destruction of Challenger as a leak in the SRB
> would not have ignited a non-existent tank.
This is a repetition of your earlier disinformation. You are clueless
about how to engineer a rocket, and even more clueless in your
'analysis' of the Shuttle disaster. I find it interesting that
someone can be so excited about space travel to have powerful opinions
about it while at the same time being absolutely ignorant of even
basics like Tsiolkovski's rocket equation.
> The only advantage to
> liquid fuel over solid is the ability to vary the burn rate.
No, the major advantage liquid fuel has over solid fuel is higher
exhaust velocity meaning smaler propellant fractions are needed to get
to orbit. A second advantage is that not all the liquid fuel is in
the engine at the same time, so liquid fuel rockets cannot explode as
solids can, which have ALL their fuel in the engine and is burning at
once. These two reasons are the primary reasons engineers gave
AGAINST SRBs - and they are sound ones - since the ET would not have
exploded if it hadn't been for a leaky SRB in the first place. Max
Faget, designer of the Mercury capsule designed a reusable shuttle
with a reusable first stage consisting of a modified Saturn S-1 stage
with F-1 engines in a larger winged stage that flew back to base after
launch. This along with using J2 engines aboard the second stage
shuttle orbiter, and ablative heat sheild that is sprayed on after
each flight - truly would have reduced costs of shuttle operation and
provided superb safety and reliability while cutting years off
development times and billions of dollars out of development budgets.
Of course, the goal of NASA in this period - according to documents
released from the Nixon White House was to NOT use Apollo era hardware
and put the memory of Apollo behind us with a totally different
configuration that wasn't too easily achieved. Otherwise, America
would use this new low-cost capability to over-spend on PAYLOADS sent
to the moon and mars.
> William Mook said of Androcles' comments;
Androcles
======================================
It's no sweat to me, Mooky, I'm happy.
We have the means, and for the past 55 years have had the means,
to do whatever the hell we wanted on planet Earth, including blowing
the insane Neanderthals to smithereens.
Meanwhile, our society rots as our Super Aryan Race stagnates while
ignorance grows greater and greater every day.
Hitler was an idealist. The only power you really need, Mooky, is
the power of persuasion. You should write speeches for politicians,
Mooky.
Androcles
No it wouldn't.
======================================
"Each engine can generate almost 1.8 meganewtons (MN) or 400,000 lbf of
thrust at liftoff."
Ref: http://en.wikipedia.org/wiki/Space_Shuttle_main_engine
3 * 1.8 = 5.4 million newtons, less than half of the thrust of one SRB.
The 786.5 tonne filled tank has a greater mass than the vehicle, idiot
Mooky. If you want to argue that take it up with a clown of your
own pathetic mentality.
So... yes it would!
Your statement is a fuckin' lie designed to leave someone with your
dumbfuck impression and your inability to perform simple arthmetic is
laughable.
William Mook
Who are the Neanderthals Andy? Those who can't do simple calculus
and are clueless about how to use the rocket equation? I'm all for it
if that's the criteria. When do you report for your termination?
> Meanwhile, our society rots as our Super Aryan Race stagnates while
> ignorance grows greater and greater every day.
Andy, you are a prime example of an arrogant clueless ass.
> Hitler was an idealist.
Hitler was an unhappy, broken and bitter man who led all who followed
him to failure and destruction. In short, he was as clueless as you
Andy.
> The only power you really need, Mooky, is
> the power of persuasion.
The results of that power depends on your appreciation of reality.
You see Andy, reality doesn't care what you think, it continues to be
what it is no matter what you believe about it.
> You should write speeches for politicians,
> Mooky.
Why?
William Mook
> "Sylvia Else" <syl...@not.at.this.address> wrote in message
>
> news:00a27e96$0$1567$c3e...@news.astraweb.com...
>
>
>
> > Androcles wrote:
> >> "Sylvia Else" <syl...@not.at.this.address> wrote in message
> >>news:0087e41e$0$16934$c3e...@news.astraweb.com...
> >>> Androcles wrote:
> >>>> "Sylvia Else" <syl...@not.at.this.address> wrote in message
> >>>>news:0087aa77$0$16905$c3e...@news.astraweb.com...
> >>>>> Androcles wrote:
> >>> Which was an entirely different ball game. It didn't go into orbit, and
> >>> never had to do a hypersonic reentry.
>
> >>>> The whole shuttle farce was a typical American government
> >>>> over-engineered mess. It's what happens when the funds are
> >>>> unlimited,
> >>> The solid-fuel boosters were used exactly because funds were limited,
> >>> and the originally proposed aircraft style reusable first stage had to
> >>> be scrapped.
>
> >>> Sylvia.
>
> >> You mean they were glued on as an afterthought when it was realised
> >> the tank had weight and the tank was bolted on as an afterthought
> >> when it was realised the shuttle wasn't big enough to carry its own
> >> fuel.
>
> > Did you read
>
> No, I knee-jerk interrupted and snipped it instead, a stupid stunt I
> learnt from you.
No, Andy, Sylvia is right. The SRBs should never have been added to
the shuttle system. The original fly back booster would have been
preferred. I calculated for you Andy a 1,400 ton three stage to
orbit rocket around SSME/ET technology - with the ET composing the
first stage - this system will place 180 tons into LEO.
Two SRBs strapped together as a first stage, with SRB style second and
third stage, would mass 1,400 ton at lift off, but put up only 5.8
tons into LEO.
This is a consequene of SRB having an exhaust speed of 2.6 km/sec and
SSME having exhaust speed of 4.5 km/sec - and both must achieve 9.2 km/
sec.
William Mook
Exactly right! A pound of SRB propellant will produce a pound of
thrust for 260 seconds. A pound of ET propellant will produce a pound
of thrust for 455 seconds. This is an important point captured in the
rocket equation;
Isp = specific impulse = 260 for SRB, 455 for SSME
Vf = Isp * g0 * LN(1/(1-u))
Where Vf = final velocity (9.2 km/sec)
Isp = specific impulse
g0 = gravity constant = 9.802 m/sec
u = propellant fraction needed achieve Vf given Isp
William Mook
The cool thing is the ability of increasing temperatures to increase
exhaust speed. Leik Myrabo's laser lightcraft achieves exhaust speeds
of 20.0 km/sec !!!!
http://www.youtube.com/watch?v=5_9ac-w4DW8
With the first stage using air heated by laser energy reducing
payloads further.
The 9.2 km/sec orbital speed with 3.07 km/sec provided by air leaves
6.13 km/sec provided by propellant - at higher altitudes
u = 1 - 1/exp(6.13/20.0) = 0.26398 ~ 0.264
So, 26.4% of the take off weight is propellant. Allowing 13.6% of the
craft to be structure, this leaves 60.0% payload!
So the 1,400 ton lift off mass - to compare to the SRB and SSME based
systems - puts 840 tons into LEO!!! WOW!
SRB 1,400 ton lift off --> 5.8 tons LEO
ET 1,400 ton lift off --> 180.0 tons LEO
LASER 1,400 ton lift off --> 840.0 tons LEO
Alternatively, a laser light craft would have to be;
9.7 tons at lift off to carry 5.8 tons to LEO
300.0 tons at lift off to carry 180 tons to LEO
Androcles
==========================================
Ignorant shits like you, Mooky. Grammatically, you need a
comma between "Neanderthals" and "Andy".
http://www.merriam-webster.com/dictionary/grammar
==========================================
Those who can't do simple calculus
and are clueless about how to use the rocket equation? I'm all for it
if that's the criteria. When do you report for your termination?
============================================
Get to the front of the line if you can't write simple English, Mooky.
============================================
> Meanwhile, our society rots as our Super Aryan Race stagnates while
> ignorance grows greater and greater every day.
Andy, you are a prime example of an arrogant clueless ass.
===========================================
Mooky, you are a prime example of an arrogant and clueless cunt
who cannot punctuate a sentence.
===========================================
> Hitler was an idealist.
Hitler was an unhappy, broken and bitter man who led all who followed
him to failure and destruction.
===========================================
Yes, he committed suicide. Clearly you cannot appreciate sarcasm
and irony. That's only to be expected from a clueless bastard like you.
Follow his example, Mooky, you are just as unhappy and bitter as
he was because you've been proven wrong, three SRBs will lift
the shuttle to orbit and then some.
===========================================
In short, he was as clueless as you
Andy.
===========================================
In short, he was as clueless as you (comma) Mooky.
===========================================
> The only power you really need, Mooky, is
> the power of persuasion.
The results of that power depends on your appreciation of reality.
===========================================
Reality is the shuttle is a piece of shit design and is being scrapped;
three SRBs are more tha capable of lifting the shuttle to orbit, dumbfuck,
since one SRB has more thrust (12.5 MN) than three engines (1.8 MN each).
Of course, a clueless shit like you is too stupid to figure that out.
===========================================
You see Andy, reality doesn't care what you think, it continues to be
what it is no matter what you believe about it.
===========================================
You don't see, Mooky, but reality doesn't care that you are blind.
It continues to be that 12.5 MN from one SRB is greater than 5.4 MN
from three engines, no matter what you believe about it.
===========================================
> You should write speeches for politicians,
> Mooky.
Why?
===========================================
Because you enjoy writing reams of ignorant crap about "King
Hubbert", Mooky. Someone might buy your shit.
Androcles
==================================================
That is the dumbest remark I've heard in a long time.
If I made a bottle rocket with a diameter of 1 cm and the same fuel
it wouldn't affect the exhaust speed by one iota. You are a complete
moron, Mooky.
<rest snipped, fault found>
William Mook
explaining that in addition to thrust one must consider final speed of
the rocket. I spent about 20 minutes calculating all the details, and
*bam* it never appeared. I redid it, and have tried posting four
times as I've said- so, I'm seeing if I can post it here.
* * * *
"William Mook" <mokmedi...@gmail.com> wrote in message
news:ec331fa9-
e771-4561-908...@t12g2000vbk.googlegroups.com...
On Dec 16, 8:40 pm, "Androcles" <Headmas...@Hogwarts.physics_q> wrote:
- Hide quoted text -
- Show quoted text -
> "William Mook" <mokmedi...@gmail.com> wrote in message
> news:2dc0abc2-234a-4048...@26g2000yqo.googlegroups.com...
> On Dec 16, 4:18 pm, "Androcles" <Headmas...@Hogwarts.physics_q> wrote:
> > "William Mook" <mokmedi...@gmail.com> wrote in message
> >news:7f437489-81ab-4cd8...@p23g2000vbl.googlegroups.com...
> > > The satellites have to be launched. This requires a launching
> > > infrastructure. Making a light-weight system on Earth and launching
> > > it is preferred.
> > > A vehicle built around a modified External Tank holding hydrogen and
> > > oxygen is the easiest way to go.
> > Being scrapped, a return to conventional multi-stage rockets is planned.
> So, the external tank is part of the space shuttle, which is a multi-
> stage rocket. Modifying the ET is still the easiest way to go.
> > > Take the Space Shuttle External Tank. It masses 26.5 metric tons
> > > empty and 760.0 metric tons filled. Equipped with a 19.6 foot
> > > diameter propulsive end cap made of a MEMs based propulsive skin that
> > > weighed 1 ton and produced 1,080 tons thrust, the revised tank would
> > > lift off with 1.4 gees.
> > It blew up Challenger.
> It wasn't the cause. A leaky seal in a section on the SRB cut through
> a support strut which caused the SRB to come loose and rupture the
> ET. The ET is a fabulous piece of engineering. Your statement is
> disinformation designed to leave someone with the wrong impression.
> ==================================================
> Three steerable re-usable SRBs producing 12.5 million newtons, EACH,
> of thrust would lift the shuttle to orbit without its 26.5 tonne tank,
No it wouldn't.
======================================
"Each engine can generate almost 1.8 meganewtons (MN) or 400,000 lbf
of
thrust at liftoff."
Ref: http://en.wikipedia.org/wiki/Space_Shuttle_main_engine
3 * 1.8 = 5.4 million newtons, less than half of the thrust of one
SRB.
Sure, it would lift off, but because of the lower performing fuels
used by the SRB - and the relatively massive structure to contain the
exhaust gases - the final speed of the configuration you mention would
be only 4.6 km/sec while orbital speed is over 6.9 km/sec.
>The 786.5 tonne filled tank has a greater mass than the vehicle, idiot
>Mooky.
That's the whole point Andy. High propellant mass - which means very
light weight structures. This is an advantage for the ET. A single
empty SRB wouldn't go faster than 5 km/sec. A single ET propelled by
three SSME at its base, would loft 78 tons into low earth orbit.
That's because 15% of the mass of an SRB is structure and only 4% of
the mass of an ET is structure. This is a good thing.
> If you want to argue that take it up with a clown of your
> own pathetic mentality.
Dude, I already did the thrust calculation and gave you gee forces at
lift off and at burn out. That will get you off the ground, but the
Shuttle will only hop across the Atlantic with the configuration you
mentioned.
Two SRBs as a first stage, with an upper stage made up of a shortened
SRB and a third stage with a solid upper stage - would loft no more
than 5.8 tons into LEO with a 1,400 ton lift off mass.
Three SSME strapped to an ET with a second stage built of a shortened
ET with a single SSME and a third stage with a RL10 engine cluster and
a smaller version of the ET would loft 180 tons into LEO - with a
1,400 ton lift off mass.
> So... yes it would!
It would lift off - it would burn out at no more than 4.6 km/sec - and
that's way short of orbit. So, no it wouldn't.
> Your statement is a fuckin' lie
No its not.
> designed to leave someone with your
> dumbfuck impression and your inability to perform simple arthmetic is
>laughable.
I did the same arithmetic you did and agree with you three SRBs
configured as you say can lift off the Shuttle. But where you
stopped, I continued. What is the burn-out speed? The answer is no
more than 4.6 km/sec. This is far short of orbital speed.
Familiarize yourself with the rocket equation;
Vf = Ve * LN( 1 / ( 1 - u ) )
Vf = final velocity (9.2 km/sec)
Ve = exhaust velocity (2.5 km/sec for SRB, 4.5 km/sec for ET/SSME)
u = propellant fraction (84% for SRB, 96%for ET)
Androcles
> I've tried responding four times to Andy's comments about thrust
> explaining that in addition to thrust one must consider final speed of
> the rocket. I spent about 20 minutes calculating all the details, and
> *bam* it never appeared. I redid it, and have tried posting four
> times as I've said- so, I'm seeing if I can post it here.
>
> * * * *
That's because you are a moron who doesn't read and posted
to a newsgroup nobody reads, Mooky.
Saturn V was a better thing. Soyuz is a better thing.
That's the whole point, Mooky. The shuttle was a step backwards
and a lethal design, crew are less expendable than payload. That's the
whole point, Mooky. Spaceship One was a solid fuel rocket. That's
the whole point, Mooky.
>> If you want to argue that take it up with a clown of your
>> own pathetic mentality.
>
> Dude, I already did the thrust calculation and gave you gee forces at
> lift off and at burn out. That will get you off the ground, but the
> Shuttle will only hop across the Atlantic with the configuration you
> mentioned.
>
> Two SRBs as a first stage, with an upper stage made up of a shortened
> SRB and a third stage with a solid upper stage - would loft no more
> than 5.8 tons into LEO with a 1,400 ton lift off mass.
Your statement is disinformation designed to leave someone with
the wrong impression.
At present:
Fact: The first stage is the SRBs, the tank and the shuttle's three engines.
Fact: The second stage is the tank and the shuttle's three engines.
Fact: The third stage is the shuttle's own onboard fuel (without the ET)
and its three engines, not all of which are needed.
Replace the tank with a 700 tonne SRB for the second stage.
>
> Three SSME strapped to an ET with a second stage built of a shortened
> ET with a single SSME and a third stage with a RL10 engine cluster and
> a smaller version of the ET would loft 180 tons into LEO - with a
> 1,400 ton lift off mass.
>
>
>> So... yes it would!
>
> It would lift off - it would burn out at no more than 4.6 km/sec - and
> that's way short of orbit. So, no it wouldn't.
With you designing it, sure. Anyone babbling about exhaust velocity
when it's the same for a bottle rocket clearly knows nothing about
thrust. The correct design for an SRB is a cone, not a cylinder.
Maximum thrust at lift off, reduced thrust (and mass) at altitude.
>
>> Your statement is a fuckin' lie
>
> No its not.
Your statement is disinformation designed to leave someone with
the wrong impression.
>
>> designed to leave someone with your
>> dumbfuck impression and your inability to perform simple arthmetic is
>>laughable.
>
> I did the same arithmetic you did and agree with you three SRBs
> configured as you say can lift off the Shuttle. But where you
> stopped, I continued. What is the burn-out speed? The answer is no
> more than 4.6 km/sec. This is far short of orbital speed.
>
> Familiarize yourself with the rocket equation;
>
> Vf = Ve * LN( 1 / ( 1 - u ) )
>
> Vf = final velocity (9.2 km/sec)
> Ve = exhaust velocity (2.5 km/sec for SRB, 4.5 km/sec for ET/SSME)
Same for a bottle rocket.
To get lift-off the thrust must match the weight to be lifted.
This has nothing whatever to do with exhaust velocity, the
Harrier has a single Pegasus engine which drives a fan.
http://tinyurl.com/nt537w
The forward nozzles blow clean, unburned air, the rear
nozzles blow the exhaust.
Learn Newton's third law, discover what 'momentum' means and
learn simple calculus. A bottle rocket won't lift a shuttle even if
you doubled it's exhaust velocity, Mooky. Two SRBs doubles
the acceleration of one. Discover the difference between acceleration
and velocity, Mooky.
Your statement is disinformation designed to leave someone with
the wrong impression.
BradGuth
> "William Mook" <mokmedi...@gmail.com> wrote in message
>
>
> > I've tried responding four times to Andy's comments about thrust
> > explaining that in addition to thrust one must consider final speed of
> > the rocket. I spent about 20 minutes calculating all the details, and
> > *bam* it never appeared. I redid it, and have tried posting four
> > times as I've said- so, I'm seeing if I can post it here.
>
> > * * * *
>
> That's because you are a moron who doesn't read and posted
> to a newsgroup nobody reads, Mooky.
>
>
>
> > "William Mook" <mokmedi...@gmail.com> wrote in message
>
> > news:ec331fa9-
"designed to leave someone with the wrong impression" is a nice way of
putting it. However, from time to time our Mook has been a wealth of
published information and subsequent notions for alternative energy
and otherwise for various adventures or investments into off-world
matters.
I would agree that our Saturn V was and perhaps still is the best fly-
by-rocket technology, and try to imagine how much better once cutting
its inert mass by 15<25% (not to mention what a few SRBs can add).
~ BG
William Mook
> Andy wrote;
>
> > > Three steerable re-usable SRBs producing 12.5 million newtons, EACH,
> > > of thrust would lift the shuttle to orbit without its 26.5 tonne tank,
>
>
> > No it wouldn't.
>
> William notes: (my explanation of the rocket equation is deleted)
>
> Andy replies:
>
> > ======================================
>
> > "Each engine can generate almost 1.8 meganewtons (MN) or 400,000 lbf of
> > thrust at liftoff."
>
>
> Sure, Andy, the SRBs will lift the Shuttle and themselves off the
> pad. I even carried out the calculation determining the gee forces at
> lift-off and the gee-forces at burn-out.
>
> That's not the issue. The issue is final speed.
>
> An object must move at around 6.9 km/sec to maintain a stable orbit
> around the Earth. Throw a ball - it follows an arc. Throw it faster
> and the arc flattens out and the ball goes farther. Without air
> resistance, you could throw a ball so that its arc has a radius of
> curvature equal to the radius of the Earth - this is orbital speed;
>
> Vo = sqrt(G*M/r)
>
> Where G = gravitational constant
> M = mass of the Earth
> r = radius of orbit (must be greater than radius of
> Earth)
> Vo = orbital velocity
>
> Like I said you need to go about 6.9 km/sec
>
> http://en.wikipedia.org/wiki/Orbital_velocity
>
> Now, the velocity of a rocket propelled projectile is given by the
> Tsiolkovsky equation
>
> Vf = Ve * LN(mi/mf)
>
> Vf = final velocity
> Ve = exhaust velocity
> LN( ) = natural log function
> mf = final mass
> mi = initial mass
>
> The Ve of the SRBs is around 2.6 km/sec
> The mi/mf of the SRB/Shuttle configuration is 5.2
>
> So, the Vf of the configuration is 2.6*LN(5.2) = 4.3 km/sec
>
> This is LESS than orbital velocity. So, you cannot get into orbit
> using three SRBs attached to a shuttle. The best you can do is lift
> off, and arc over the Atlantic and land somewhere in the Indian Ocean.
>
> > Ref: http://en.wikipedia.org/wiki/Space_Shuttle_main_engine
>
> > 3 * 1.8 = 5.4 million newtons, less than half of the thrust of one SRB.
>
> Shuttle off the pad, they cannot however place it in orbit. They
> cannot even place themselves in orbit. That's because the SRBs have
> an exhaust velocity of 2.6 km/sec and they must achieve 6.9 km/sec
> minimum - with air and gravity drag losses - 8.3 km/sec or so. It
> cannot be done - which is WHY NASA used an ET to carry the higher
> performing oxygen/hydrogen fuel which when burned in the SSME has an
> exhaust velocity of 4.5 km/sec.
>
> > The 786.5 tonne filled tank has a greater mass than the vehicle,
>
>
> The SRB when filled with solid rocket fuel has greater mass than the
> vehicle too!
>
> That's the point!
>
> Propellant weights many times that of the payload are needed to attain
> orbit.
>
> Grok this and you are well on your way to understanding how rockets
> work.
>
> It is useful to compare and contrast two rocket types a solid rocket
> with an exhaust speed of 2.6 km/sec and a liquid rocket with an
> exhaust speed of 4.5 km/sec.
>
> We'll fashion BOTH rockets which will be designed to attain a stable
> orbital speed after air and gravity drag losses - both will therefore
> achieve a final ideal speed of 9.2 km/sec - the same now achieved by
> the Space Shuttle.
>
> Alright, how much of the rocket must be propellant? This is the point
> you missed Andy.
>
> For the solid rocket the propellant fraction (u) is;
>
> u = 1 - 1/EXP(Vf/Ve) = 1 - 1/EXP(9.2/2.6) = 0.97094
>
> 97.1% of the rocket must be propellant, leaving only 2.9% of the
> rocket as structure and payload.
>
> The Shuttle SRBs which are the best in the business have a propellant
> fraction of 0.8539 - 85.4% - so they cannot attain orbit! Since they
> cannot attain orbit lifting nothing - they cannot attain orbit lifting
> something.
>
> Gross Mass: 589,670 kg (1,299,990 lb).
> Empty Mass: 86,183 kg (190,000 lb).
>
>
> This is why staging is used.
>
> When we divide the rocket into three stages, we take the cube root of
> the dimensionless propellant fraction - so, things get considerably
> better.
>
> Its best to go back to basics and figure out things by dividing the
> velocity by the number of stages. So, we wanted to design a rocket
> that achieved 9.2 km/sec therefore dividing that figure by 3 gets us
> 3.07 km/sec. This is the design speed for EACH of the 3 stages.
> (we'll leave optimization aside since this takes calculus of
> variations to solve it -lets get the basics first)
>
> The SRB propellant has an exhaust velocity of 2.6 km/sec so the
> propellant fraction needed to achieve this reduced speed is;
>
> u = 1 - 1/exp(3.07/2.6) = 0.6929575
>
> that's abut 69.3% propellant. Since 14.6% is structure, this leaves
>
> 1 - 0.693 - 0.146 = 0.161
>
> 16.1% of the original mass as payload!
>
> So going back to the SRB we have 589,670 kg. The SRB lifts a SMALLER
> mini-SRB atop its nose, and fires it after it burns out.
>
> What's the size of it?
>
> 0.161 /(0.693 + 0.146) - 0.191895 ~ 0.191
>
> It's 19.1% of the SRB weight or 112,626 kg.
>
> 589,670 * 0.191 = 112,626
>
> This is the second stage third stage and payload.
>
> 19.1% of THAT weight is the third stage, and 19.1% of that payload is
> the payload you can put on orbit with SRB technology;
>
> 705,207 kg - at lift off
> 589,670 kg - stage 1 (SRB adapted to first stage)
> 94,494 kg - stage 2 (Castor series adapted to 2nd stage)
> 18,132 kg - stage 3
> 2,911 kg - payload
>
> So, this is how you can do it. And thrust isn't a problem as you
> pointed out. Shaping the cavity so that burning surface is reduced as
> the solid burns allows us to control thrust - so, you're wrong in
> saying that you cannot control the thrust of a solid rocket. You can
> - you program it in by controlling burn rates and shape of the burning
> surface in the solid. This lets you maintain optimal thrust as you
> fly your Goddard ascent curve.
>
> Now, lets look at the liquid fuel technology represented by the ET and
> SSME combination.
>
> Exhaust velocity is 4.5 km/sec for this system and final velocity is
> the same 9.2 km/sec. Applying the same rocket equation as we did
> before using these performance figures obtains;
>
> u = 1 - 1/exp(9.2/4.5) = 0.8705479 ~ 0.871
>
> 87.1% propellant fraction.
>
> The external tank figures are;
>
> Gross Mass: 750,975 kg (1,655,616 lb).
> Empty Mass: 29,930 kg (65,980 lb).
>
> So, u = (750,975 - 29,930) / 750,975 = 0.9602
>
> around 96%
>
> The SSME produces 6,834.303 kN (1,536,412 lbf) thrust. So, TWO SSME
> can lift an External Tank with sufficient acceleration to be useful.
> Three SSME can do an even better job.
>
> So, this is interesting. You only need 87.1% propellant fraction and
> structure fraction is 4% - this leaves;
>
> 1 - 0.871 - 0.04 = 0.089
>
> or 8.9% of the lift off weight to orbit. This is
>
> 0.089/(0.871+0.04) = 0.097695 ~ 0.097
>
> 9.7% of the ET by itself - so,
>
> 750,975 * 0.097 = 72,884 kg
>
> Taking away the 16,600 kg for the three SSME this leaves 56,244 kg
> payload - which is 20x more than the 3stage SRB based system.
>
> Now lets do the same calculation for a 3 stage system using SSME/ET
> technology. We want to design three stages, with the ET/SSME first
> stage, each stage to achieve 3.07 km/sec.
>
> Going back and calculating propellant fraction;
>
> 1 - 1/exp(3.07/4.5) = 0.49450757 ~ 0.495
>
> 49.5% propellant fraction. So, the total vehicle weight is
>
> Gross Mass: 750,975 kg (1,655,616 lb).
> Empty Mass: 29,930 kg (65,980 lb).
>
> (750,975-29,930)/0.495 = 1,456,656 kg
>
> So, the three SSME can lift the whole 3 stage assembly off the pad at
> 1.435 gees - which is nearly optimal.
>
> But what we're interested in is how does staging affect payload to
> orbit for a vehicle this size?
>
> Well, subtract off the fully loaded first stage to get the remaining
> stages
>
> 1,456,656 - 750,975 = 705,681 kg
>
> A single SSME drives this to 0.99 gees - which at 3.07 km/sec -
> downrange, and flying horizontally - is sufficient to carry the stage
> through its flight cycle.
>
> Multiply by 50.5% to get the third stage plus payload
>
> 705,681 * 0.505 = 353,369 kg
>
> Subtract the two figures to get second stage weight
>
> 705,681 - 353,369 = 349,312 kg
>
> Multiply the third stage plus payload mass by 50.5% to get the payload
> portion
>
> 356,369 kg * 0.505 = 179,996 kg
>
> 1.8 TIMES the payload of the Saturn V moon rocket!!!
>
> And nearly 100x the payload lofted to orbit by an SRB based vehicle.
>
> Subtract the two figures to get the third stage weight
>
> 356,369 - 179,966 = 176,403 kg
>
> Okay so lets put this in a table side by side, after doubling up the
> SRB - using two SRBs for the first stage, and this doubles the
> payload;
>
> Vehicle Type SRB ET/SSME
>
> One Stage to Orbit infeasible 72,884 kg
> Take off mass - 823,859 kg
>
> Three Stage to Orbit 5,822 kg 179,996 kg
> Take off mass 1,410,314 kg 1,456,656 kg
>
> So, for comparable sized vehicles, 31x the mass to orbit could be put
> up by an ET/SSME system when compared to the SRB system.
>
> Andy continues;
>
> >idiot
> > Mooky.
>
> Not at all. I computed take off gee forces and burn out gee forces -
> which do not tell you what the burn out speed is! The rocket equation
> gives you that.
>
> You repeated the gee force calculation and erased the rocket equation
> calculation that gives you final speed.
>
> > If you want to argue that take it up with a clown of your
> > own pathetic mentality.
>
> a rocket go? The rocket expels material out the back to push the
> rocket forward. How fast and how much determines how fast the rocket
> goes. Using Newton's laws and looking at the problem of an
> accelerating rocket we have
>
> F = dm/dt * Ve = m * dV/dt
>
> Where F = thrust
> dm/dt = mass flow rate of propellant
> Ve = exhaust velocity
> m = mass of the rocket
> dV/dt = acceleration of the rocket
>
> re-arranging terms we have
>
> (dm/dt)/m = (dv/dt)/Ve
>
> and integrating we have
>
> ln(m(t)/m) = V(t)/Ve + C
>
> Starting at lift off for the initial point, and ending at burn out at
> the last point - we solve this equation to obtain
>
> ln(m(empty)/m) = V(final) / Ve
>
> rearrange to obtain the form
>
> Vf = Ve * ln (mf/mi)
>
> to calculate the speed of a stage
>
> rearrange to obtain the form
>
> (mi-mf)/mi = u = 1 - 1/exp(Vf/Ve)
>
> and there you have it.
>
> Rockets
>
> SRB Ve=2.6 km/sec
> SSME Ve=4.5 km/sec
>
> Missions
>
> Orbital Vf= 9.2 km/sec
> Escape Vf=12.0 km/sec
>
> > So... yes it would!
>
> The SRBs certainly have enough thrust to lift the Shuttle as you
> describe, but the configuration you have outlined would only achieve
> 4.6 km/sec by the time they burned out. So, this would not be enough
> for orbit. It would be enough to loft the Shuttle on a sub-orbital
> trajectory over the Atlantic, and by gliding - it would land somewhere
> in the Indian ocean.
>
> The only way an SRB technology will send something to orbit is to
> divide the task into stages. Two SRBs would loft 5.6 metric tons into
> orbit by adding two more stages to solid stages to them as described.
>
> The ET/SSME technology will send something 78 metric tons into orbit
> without staging. If the same staging system is applied to the ET/SSME
> that payload to orbit increases to nearly 180 metric tons -
> interestingly the three SSME are enough to do the job and the size of
> the rocket at take off is nearly the same 1,400 metric tons for
> each.
>
> This is a good example of how important exhaust velocity and mass
> ratio is to good rocket design. The ET is an incredible system - and
> so is the SRB. The ET though is hands down winner for large launcher
> capability. The SRB derived vehicle can be used to loft smaller
> vehicles payloads reliably as well. Given the cost of solids versus
> hydrogen/oxygen - not cheaply however - assuming fully reusable
> systems.
>
> > Your statement is a fuckin' lie
>
> the gee forces at lift off and burnout. That's not the issue. The
> issue is the speed needed to maintain orbit and the speed the rocket
> is capable of imparting to the shuttle. Thrust is one factor. The
> other factor is the amount of time that thrust can be delivered. An
> SRB can deliver 1 pound of thrust for 260 seconds using 1 pound of
> propellant. An SSME/ET can deliver 1 pound of thrust for 455 seconds
> using 1 pound of propellant. haha - are you getting it? - The rocket
> equation lets you calculate how fast a rocket will go given the
> propellant fraction and exhaust speed of the rocket.
>
> Exhaust speed is related to specific impulse by;
>
> Vf = g0 * Isp
>
> g0 = 9.802 m/sec/sec in SI units
> = 32.2 ft/sec/sec in english units
>
> > designed to leave someone with your
> > dumbfuck impression and your inability to perform simple arthmetic is
> > laughable.
>
> configured as you describe. It will not attain orbit, it will achieve
> at most 4.6 km/sec which will take it as far as the Indian ocean when
> launched from Florida in an Easterly direction.
>
> Two SRB lofting two smaller SRB stages is capable of putting up 5
> metric tons to LEO with a 1,400 ton lift off mass.
>
> A single ET by itself with 3 SSME at its base, is capable of putting
> up over 70 metric tons to LEO with a 750 ton lift off mass.
>
> A single ET operating as a first stage, with 3 SSME lifting it,
> pushing two smaller stages - the second stage with a single SSME, and
> the third stage with another SSME or some smaller system - like RL10
> or J2 - is capable of putting up nearly 180 tons to LEO with a 1,400
> ton lift off mass.
William Mook
> On Dec 18, 10:18 pm, "Androcles" <Headmas...@Hogwarts.physics_q>
> would indeed lift the configuration you mentioned. That's not the
> issue. The issue is the speed they attain. Orbital speed is 6.9 km/
> sec and the speed 3 SRBs attain with a Shuttle attached is 4.3 km/
> sec. This means the Shuttle configured as you mention would be tossed
> across the Atlantic from Florida, and glide to a recovery in the
> Indian Ocean.
>
> SRB technology can make it to orbit. In stages. A three stage
> rocket, consisting of two SRBs as the first stage, a short SRB second
> stage, and a solid upper third stage can loft 5.8 tons into the same
> orbits as the shuttle. The entire vehicle masses 1,400 tons at lift
> off.
>
> ET/SSME technology can make it to orbit in a single stage. An ET with
> three SSME at its base, can toss 78 tons into the same orbits as the
> Shuttle with a 760 ton lift off weight. Done in stages this increases
> to 180 tons into LEO, and the same 1,400 tons at lift off. Which
> provides a good comparison with the SRB approach.
>
> This is all due to differences in SPECIFIC IMPULSE - how many seconds
> of thrust can a unit of fuel produce? A rocket producing a pound
> force of thrust burns through a pound of fuel in 260 seconds in the
> SRB and 455 seconds in the SSME/ET - this difference in time provides
> for tremendous difference in performance.
William Mook
> On Dec 18, 10:18 pm, "Androcles" <Headmas...@Hogwarts.physics_q>
> attached to the Shuttle would burn out at 4.6 km/sec and it would be
> lofted into a sub-orbital flight - coming down on the other side of
> the Atlantic, gliding across Africa to the Indian ocean when launched
> from Florida.
>
> This is because the mass ratios and the exhaust speeds of the SRB are
> not sufficient to achieve the speeds needed.
>
> The shuttle ideally attains 9.2 km/sec. To have the same performance
> any rocket would need to achieve the same final speeds.
>
> The rocket equation gives us a way to calculate a rocket's speed.
>
> Vf = Ve*LN(1/(1-u))
>
> or
>
> u = 1 - 1/EXP(Vf/Ve)
>
>
> Ve = 2.6 km/sec for the SRB
> Ve = 4.5 km/sec for the ET/SSME
>
> Two SRBs strapped together carrying a second stage mini-SRB and a
> third stage micro-SRB - would weigh 1,400 tons at lift off and carry
> 5.8 ton to the same orbits as the Shuttle.
>
> An ET powered by 3 SSME carrying a mini ET atop it, powered by a
> single SSME and a micro ET atop that, powered by J2, would weigh
> 1,400 tons at lift off and carry 180 tons to the same orbits as the
> shuttle.
>
> A laser lightcraft powered by a solar pumped laser in space has an
> exhaust speed of 20.0 km/sec - and uses air when low in the atmosphere
> - to achieve 3.07 km/sec with zero fuel - using laser energy to create
> a laser powered rocket - massing 1,400 tons at lift off, can carry 840
> tons to orbit.
>
> Type SRB SSME/ET LASER
>
> Ve 2.6 km/sec 4.5 km/sec 20.0 km/sec
> Vf 9.2 km/sec 9.2 km/sec 9.2 km/sec
> TOW 1,400 tons 1,400 tons 1,400 tons
> LEO 5.6 tons 180 tons 840 tons
>
>
>
> > Your statement is a fuckin' lie
>
>
> > designed to leave someone with your
> > dumbfuck impression and your inability to perform simple arthmetic is
> > laughable.
>
> calculation to determine speed.
William Mook
> absolutely no sense. Exhaust speed is related to specific impulse by
>
> Ve = g0 * Isp
>
> Where Ve = exhaust speed in m/sec
> g0 = gravity constant 9.802 m/sec/sec
> Isp = specific impulse sec
>
> The SRBs have a specific impulse of 260 seconds exhaust speed of about
> 2.5 km/sec
>
> The SSME/ET have a specific impulse of 455 seconds exhaust speed of
> about 4.5 km/sec
>
> The LASER light craft have a specific impulse of 2,200 seconds exhaust
> speed of about 20.0 km/sec
>
> This has dramatic impact on final speed, since
>
> Vf = Ve * LN(1/(1-u))
>
> or
>
> u = 1 - 1/exp(Vf/Ve)
>
> Where Vf = final speed of the rocket
> Ve = exhaust speed of rocket
> u = propellant fraction
>
> The SRBs are about 86% propellant. The ET is 94% propellant. Orbital
> speed is 6.9 km/sec but the Shuttle achieves 9.2 km/sec - enough to
> fly in higher orbits, even with gravity losses and air drag.
>
> So, Vf = 9.2 km/sec.
>
> Its obvious that the higher the Vf the lower the u - propellant
> fraction.
William Mook
> but what its the speed of the configuration when the SRBs burn out?
> The answer is given by the rocket equation - and given the masses
> involved, not counting losses, that's 4.6 km/sec. This is not orbital
> speed Andy, its enough to toss the Shuttle across the Atlantic, and
> let it glide over Africa to land in the Indian Ocean.
>
> > > You should write speeches for politicians,
> > > Mooky.
>
> > Why?
> > ===========================================
> > Because you enjoy writing reams of ignorant crap about "King
> > Hubbert", Mooky. Someone might buy your shit.
>
> curve as it relates to oil. Hubbert did that in the 1950s. The
> logistic curve applies to anything you look for in a field of other
> things. Look for dimes in a coin jar filled with lots of different
> type coins and you will get a logistic curve. Look for red marbles in
> a jar filled with white and red marbles and you will get a logistic
> curve. Look for oil in a geographic region and you will get a
> logistic curve.
>
> What's a logistic curve? Its a curve that is produced when you are
> extracting a thing from a fixed reserve. There are only so many dimes
> in the coin jar. Only so many red marbles in the marble jar. Only so
> much oil in the world. So, the first coin, the first marble, the
> first barrel of oil is easiest to find. The next one easy. Things
> get harder each time you take one from the field of exploration.
> After you reach the half way point, things get considerably harder -
> this is the peak production point - whether its dimes in coin jars,
> red marbles in a marble jar, or oil from Earth.
>
> http://mathdemos.gcsu.edu/mathdemos/logistic/logistic.html
>
> There is nothing ignorant about any of this Andy.
William Mook
> On Dec 19, 6:06 pm, "Androcles" <Headmas...@Hogwarts.physics_q> wrote:
>
>
>
> > "William Mook" <mokmedi...@gmail.com> wrote in message
>
> > On Dec 19, 4:58 pm, William Mook <mokmedi...@gmail.com> wrote:
>
> > > On Dec 17, 5:09 am, "Androcles" <Headmas...@Hogwarts.physics_q> wrote:
>
> > > > "Sylvia Else" <syl...@not.at.this.address> wrote in message
>
> > > >news:00a27e96$0$1567$c3e...@news.astraweb.com...
>
> > > No, Andy, Sylvia is right. The SRBs should never have been added to
> > > the shuttle system. The original fly back booster would have been
> > > preferred. I calculated for you Andy a 1,400 ton three stage to
> > > orbit rocket around SSME/ET technology - with the ET composing the
> > > first stage - this system will place 180 tons into LEO.
>
> > > Two SRBs strapped together as a first stage, with SRB style second and
> > > third stage, would mass 1,400 ton at lift off, but put up only 5.8
> > > tons into LEO.
>
> > > This is a consequene of SRB having an exhaust speed of 2.6 km/sec and
> > > SSME having exhaust speed of 4.5 km/sec - and both must achieve 9.2 km/
> > > sec.
>
> > ==================================================
> > That is the dumbest remark I've heard in a long time.
> > If I made a bottle rocket with a diameter of 1 cm and the same fuel
> > it wouldn't affect the exhaust speed by one iota. You are a complete
> > moron, Mooky.
> > <rest snipped, fault found>
>
> combustion chamber. The temperatures and pressures achieved with
> solid rocket propellants is far less than those achieved with liquid
> rocket propellants. This is a function of specific energy and
> molecular weight. That's why the SSME runs hydrogen rich - to lower
> the molecular weight. Stoichiometric ratio is 8 to 1 oxygen to
> hydrogen - and the SSME runs 6 to 1.
>
> Then, once you have a given specific energy per unit weight of
> reaction gas in a combustion chamber a convergent nozzle accelerates
> the gas to local sound speed, and then diverges once supersonic flow
> is achieved, to further accelerate it to 3 to 5 times sound speed at
> the exhaust.
>
> A bottle rocket wouldn't be able to withstand the pressures and
> temperatures achieved by either solid or liquid rocket propellants.
>
> So, your comment doesn't make any sense Andy.
>
> Vf = Ve*ln(1/(1-u))
>
> Vf=final velocity
> Ve=exhaust velocity
> ln(..) = natural log function
> u = propellant fraction
William Mook
> On Dec 20, 10:51 pm, "Androcles" <Headmas...@Hogwarts.physics_q>
>
> > > I've tried responding four times to Andy's comments about thrust
> > > explaining that in addition to thrust one must consider final speed of
> > > the rocket. I spent about 20 minutes calculating all the details, and
> > > *bam* it never appeared. I redid it, and have tried posting four
> > > times as I've said- so, I'm seeing if I can post it here.
>
> > > * * * *
>
> > That's because you are a moron who doesn't read and posted
> > to a newsgroup nobody reads, Mooky.
>
> > > "William Mook" <mokmedi...@gmail.com> wrote in message
>
> > > news:ec331fa9-
> the heat shield tile is better per unit weight than ablative systems,
> the structural fraction of the ET is superior to the structural
> fraction of the Saturn V.
>
> > Soyuz is a better thing.
>
> superior to it.
>
> > That's the whole point, Mooky. The shuttle was a step backwards
> > and a lethal design,
>
> with Kennedy and he wanted something the public would associate with
> him. He put Agnew in charge of a committee to review space travel
> post-Apollo. NASA gave him a laundry list, thinking they would do ALL
> of it. He turned around and said PICK ONE! The Shuttle was the first
> item on the list, and that's what got picked. Max Faget and others
> proposed a very low-cost version of the Shuttle, that reused a lot of
> the Apollo era hardware. F1s in the first stage, ablative heat
> sheild, J2s in the upper stages, in a fly-back configuration - that
> would have cost less than Skylab and gotten done in three years.
>
> http://www.astronautix.com/graphics/b/bsts70b.jpg
>
> With FULL reusability, and NO throw-away parts.
>
> DOD pissed in the pot, and didn't like the cross-range limits of
> Faget's design. They wanted to 'push the envelope' in design - and
> over designed the SSME and heat shield. Then, after wasting tons of
> money on stuff that only delayed things, NASA faced a cutback and the
> Stage and one-half Shuttle was born - with SRB add-on which was a
> terrible choice for the vehicle - which Challenger later proved - and
> an expendable ET which blew the recurring budget.
>
> NASA quoted figures in 1969 based on a certain design and flight
> rate. Then, they were beat over the head for the next 30 years about
> how wrong they were - even though it was never mentioned publicly
> that
>
> a) Congress changed the design;
>
> b) Congress radically reduced the flight-rate;
>
> c) Congress never authorized improvements at launch site to reduce
> costs - in fact due to budget constraints, they outsourced propellant
> which increased costs dramatically
>
> Its as if there were a contingent in Congress that wanted to kill NASA
> and thought by saddling the agency with the Shuttle and spouting off
> about the failings of the agency in that regard, the could do it.
>
> > crew are less expendable than payload.
>
> are designed as safely as they can be. There is nothing inherent in
> the Saturn V design that made is unsafe. In fact, there was never a
> single loss of a Saturn launch vehicle EVER.
>
> >That's the
> > whole point, Mooky.
>
> clueless prejudices and showing just how ignorant you are about things
> you claim to care a lot about.
>
> > Spaceship One was a solid fuel rocket.
>
> liquid oxidizer; (rubber and nitrous oxide)
>
> http://www.msnbc.msn.com/id/5226424/ns/technology_and_science-space/
>
> http://www.astronautix.com/craft/spaipone.htm
>
> Which had a specific impulse of 250 seconds - a little less than the
> SRB, and given the propellant fraction quoted, is only enough to do
> suborbital flights.
>
> > That's
> > the whole point, Mooky.
>
> by the rubber/nitrous oxide combination were easily handled by the
> ablative nozzle? That the high molecular weight of the exhaust
> product were relatively unaffected by the high molecular weight
> ablative material in the nozzle?
>
> hmm..
>
> > >> If you want to argue that take it up with a clown of your
> > >> own pathetic mentality.
>
> > > Dude, I already did the thrust calculation and gave you gee forces at
> > > lift off and at burn out. That will get you off the ground, but the
> > > Shuttle will only hop across the Atlantic with the configuration you
> > > mentioned.
>
> > > Two SRBs as a first stage, with an upper stage made up of a shortened
> > > SRB and a third stage with a solid upper stage - would loft no more
> > > than 5.8 tons into LEO with a 1,400 ton lift off mass.
>
> > Your statement is disinformation designed to leave someone with
> > the wrong impression.
>
>
> > At present:
> > Fact: The first stage is the SRBs, the tank and the shuttle's three engines.
>
> Variations you will see why SRBs during the FIRST FEW MINUTES OF
> FLIGHT reduce vehicle size. SRBs used throughout reduce payload
> fraction to orbit as I've calculated several times.
>
> > Fact: The second stage is the tank and the shuttle's three engines.
>
> enters its programmed role maneuver, it doesn't need as much thrust.
> Notice that when the SRBs fall away the Shuttle is moving nearly
> horizontally, so nearly all the energy is going to accelerate the
> craft, not lift it.
>
> > Fact: The third stage is the shuttle's own onboard fuel (without the ET)
>
> little. It is lower performing than SSME/ET propellant, but really
> doesn't matter since its for maneuvering only - and storeability and
> ease of ignition and so forth are the issues there.
>
> > and its three engines, not all of which are needed.
>
> they're all needed, with about 10% over - as the ET drains thrust is
> cut back to keep acceleration down which reduces structural mass - as
> I said you need to know Calculus of Variations to compute an optimal
> system.
>
> I do agree with you that the Shuttle is a kludge. What should have
> been done is to use F1s - Lox-Kerosene for a first stage fly back
> booster and J2s - Lox-Liquid Hydrogen for the second orbiter stage and
> use a NERVA reusable deep space stage for lunar and mars operations.
> This could all have been done in less time and less cost than the
> Shuttle.
>
> The 'wet-stage' modifications to the S-II and S-IVB could have been
> applied to a nuclear stage to provide a lunar base and mars base at
> very low cost.
>
> > Replace the tank with a 700 tonne SRB for the second stage.
>
>
> > > Three SSME strapped to an ET with a second stage built of a shortened
> > > ET with a single SSME and a third stage with a RL10 engine cluster and
> > > a smaller version of the ET would loft 180 tons into LEO - with a
> > > 1,400 ton lift off mass.
>
> > >> So... yes it would!
>
> > > It would lift off - it would burn out at no more than 4.6 km/sec - and
> > > that's way short of orbit. So, no it wouldn't.
>
> > With you designing it, sure.
>
>
> > Anyone babbling about exhaust velocity
> > when it's the same for a bottle rocket clearly knows nothing about
> > thrust.
>
> out that's the important figure and that's given by the exhaust
> velocity and propellant fraction.
>
> > The correct design for an SRB is a cone, not a cylinder.
>
>
> > Maximum thrust at lift off, reduced thrust (and mass) at altitude.
>
> better solutions - it doesn't change the specific impulse
> unfortunately.
>
>
>
> > >> Your statement is a fuckin' lie
>
> > > No its not.
>
> > Your statement is disinformation designed to leave someone with
> > the wrong impression.
>
> provided.
>
>
>
> > >> designed to leave someone with your
> > >> dumbfuck impression and your inability to perform simple arthmetic is
> > >>laughable.
>
> > > I did the same arithmetic you did and agree with you three SRBs
> > > configured as you say can lift off the Shuttle. But where you
> > > stopped, I continued. What is the burn-out speed? The answer is no
> > > more than 4.6 km/sec. This is far short of orbital speed.
>
> > > Familiarize yourself with the rocket equation;
>
> > > Vf = Ve * LN( 1 / ( 1 - u ) )
>
> > > Vf = final velocity (9.2 km/sec)
> > > Ve = exhaust velocity (2.5 km/sec for SRB, 4.5 km/sec for ET/SSME)
>
> > Same for a bottle rocket.
>
> or SSME/ET. You can get an idea about how specific impulse changes
> performance by propelling a bottle rocket in a variety of ways.
>
> This is a good page to follow to learn a little more about rockets and
> how they work;
>
> http://www.mrp3.com/bobf/pepsi_rocket0.html
>
> Use bleach and hydrogen peroxide - the rocket will fly differently
> than when pressurized by air - even though they both give the same
> amount of thrust. Why? Because they have different specific
> impulse. Same with the SRB and SSME/ET
>
> > To get lift-off the thrust must match the weight to be lifted.
>
> question. That requires Calculus of Variations was well to answer
> properly. For most rockets its 1.4 to 1.8 gees at lift off.
>
> > This has nothing whatever to do with exhaust velocity,
>
> propellant;
>
> F = mdot * Ve
>
> F=newtons
> mdot = kg/sec
> Ve=m/sec
>
> So, if you have so many pounds you're lifting you need lift fewer
> pounds of propellant with a higher mdot to get the same final speed
> see?
>
> That's why
>
> Vf = Ve * ln (1/(1-u))
>
> Vf=final velocity
> Ve=exhaust velocity
> ln(..) = natural log function
> u=propellant fraction
>
>
> >the
> > Harrier has a single Pegasus engine which drives a fan.
> > http://tinyurl.com/nt537w
> > The forward nozzles blow clean, unburned air, the rear
> > nozzles blow the exhaust.
>
> energizing the air by burning a fuel. Here, the fuel is only
> providing a portion of the mass flow - so, you get an increase in
> specific impulse - to about 2,000 seconds of thrust per pound of fuel
> burned in this way.
>
> > Learn Newton's third law, discover what 'momentum' means and
> > learn simple calculus.
>
> it isn't the most important one here. The first law as it applies to
> variable mass systems (you're throwing propellant out the back so its
> variable mass) is the ticket;
>
> http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Variable-mass_...
>
> > A bottle rocket won't lift a shuttle even if
> > you doubled it's exhaust velocity,
>
>
> > Mooky.
>
> Andy.
>
> > Two SRBs doubles
> > the acceleration of one.
>
> derived 3 stage rocket - which gives a neat demonstration of the
> importance of exhaust velocity.
>
> > Discover the difference between acceleration
> > and velocity, Mooky.
>
> integrated over time yields velocity. Notice the importance of time
> here? So, a pound of propellant that provides the same thrust for
> MORE TIME than another propellant delivers a rocket that has a higher
> final velocity than the lower performing propellant. Simple Calculus.
>
> > Your statement is disinformation designed to leave someone with
> > the wrong impression.
>
>
> > > u = propellant fraction (84% for SRB, 96%for ET)
>
>
> Higher propellant fraction higher Isp means the ET provides the bulk
> of the orbital energy while the SRB only lifts the Shuttle off the
> pad.