Flyback boosters

On Tue, 04 Sep 2007 15:26:57 GMT, (Derek Lyons)
wrote:

Jim in Houston wrote:

My mind is far from made up. This group is about exchange of
information.

Then why am I the one providing information, and you are the one
posting dogma?

Isn't exchange of information people supplying information to each
other?

Failure to adress the points I raised noted. As I said, I'm the one
providing information and discussion and you - aren't.

Convince me otherwise, but offer up facts instead of conjecture.

ROTFLMAO. Consider taking this advice yourself. (And for someone who
takes me to task for my behavior, you toss around ad hominems pretty
freely.)
Derek learned a new word, and is able to use it in a sentence, see...
exchange of information!!!
Besides, I am not the one with a tag line resolving to be more
temperate in his posts.

Personal attacks noted, again with the lack of response to the points
I raised.

D.
Notation noted, move to kill file accomplished. Conversation too
energy consuming. Bye now.
Jim in Houston.

Contrary to popular opinion RN does not mean Real Nerd!
Teddy Roosevelt's mother said: "Fill what is empty,
empty what is full, and scratch where it itches"

--
Posted via a free Usenet account from http://www.teranews.com

Jim in Houston wrote:

Notation noted, move to kill file accomplished. Conversation too
energy consuming.

ROTFLMAO

Translated into English: "faced with facts that don't agree with my
preconcieved notions, and lacking the wit to actually discuss them or
the ability to refute them, I retreat from the field claiming
victory".

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

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

On Sep 4, 2:25 pm, "Jeff Findley" wrote:
"Jim in Houston" wrote in messagenews:1fmnd3t1jucnva5tofioaprnob2euc2b3j@4ax .com...

On Mon, 03 Sep 2007 00:26:40 -0000, wrote:

A dozen fully resusable vehicles fully interoperable ranging in
payloads from 1/2 ton to 1000 tons - ranging in speeds from suborbital
to solar system escape-
.
Way above my level of understanding, but thank you for trying.

Don't worry. Everything Mookie writes is beyond his level of understanding
as well. This is why he's living in my newsreader's killfile hell.

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)

Jeff has difficulty with reality. He likes to project his
inadequacies onto others. lol.

For the record, I am formally trained in Aeronautical and
Astronautical Engineering, I'm a memberr of The American Institute of
Aeronautics and Astronautics (AIAA) and here's a paper on a modular
approach using Shuttle infrastructure, to creating a low-cost flyback
booster system;

http://www.starbooster.com/AIAA-2001-3960.pdf

Check out the 650 Heavy launcher depicted on page 9.

Jim, the flyback booster concept has a long history.

When the Titan was being used to launch Gemini capsules into space,
engineers proposed the flyback Winged Titan. .

http://www.astronautix.com/lvs/wintitan.htm
http://www.astronautix.com/graphics/t/titnwing.gif

Before that, von Braun, who built the V2 rocket for Germany in World
War 2 - and was captured by the Americans and worked on the US rocket
program from the 1940s through the 1960s - and developed rockets at
Redstone Arsenal such as the Redstone, the Atlas, the Jupiter,and the
Saturn rockets - many of which are still in use today (the Jupiter
evoled into Delta, the Atlas is still flying)

Check out this 1956 plan by vonBraun -

http://www.astronautix.com/lvs/vonn1956.htm

Very much like the winged rockets described above..

Check out the wings on the first stage. I can't find the images I'm
looking for online, but back in the 1950s, there was a magazine
article that appeared in McCall's, and Walt Disney was inspired to
make a series of movies depicting them, which are not shown much these
days.

Anyway, I remember when these came out - very exciting. They showed
parachutes being deployed to recover all 3 stages - for reuse - to
lower costs.

Of course this was never done- again I don't know why. It makes a lot
of sense - if the engineering is done appropriately.

Here's a more complete run down of von Braun designs

http://www.astronautix.com/lvfam/vonbraun.htm

Von Braun was the principal author of the New Horizons study done
after World War 2. Von Kaman, von Braun, and other captured rocket
scientists wrote it. It was immediately classified, but was
declassified years later. Even so, I cannot find a pointer to it
anywhere...

Here he called on the US to mount an expedition to the moon and
construct a missile base there - to provide assured response in case
the US suffered a nuclear attack. Since it takes 4 days for a rocket
to get to the moon, an attacker would have to launch first against the
base signalling an attack on the US by 4 days - or suffer retaliation
from the moon after an attack against the US.

Just putting an object in orbit, would establish the US as the
preiminent scientific power of the age - and add depth to our mastery
of nuclear power. Putting a man in space would inspire global
cooperation with our goals and put us geopolitically leagues above
anyone else.

http://www.ascho.wpafb.af.mil/START/CHAP7.HTM

This idea languished until Sputnik, and even then, Eisenhower dragged
his feet. The idea of a bunch of former NAZI scientists with nuclear
weapons at an unassailable base on the moon may have frightened him!
lol.

Von Braun wanted to go to Mars, and saw his reusable launchers and a
space station as a stepping stone toward this end.

http://www.press.uillinois.edu/pre95/0-252-06227-2.html

He caught JFKs attention and imagination back in 1961, when Gagarin
beat Shepherd into space - which resulted in JFKs Rice speech where he
put the US on course to the moon, and to the other things - nuclear
space propulsion to support a moon base and mars expedition - until he
was killed in November 1963.

http://www1.jsc.nasa.gov/er/seh/ricetalk.htm

So, as far back as 1945 the US leadership was being urged by their
best and brightest to develop reusable space launch capacity -
centered around a flyback booster - either recoverable downrange,or
flyback to the launch center by some means
..
A well designed system has the potential to reduce costs
dramatically. A poorly designed system does not. The details of what
it takes to design a workable rocket to put things precisely into
orbit and bring them back safely, are classified. In fact the US is
dedicated to containing this knowledge - and so, unlike designing
processor chips, or bridges, or aircraft, this knowledge is not
generally appreciated or widely known.

http://www.osti.gov/energycitations/...sti_id=7242628

And when anyone speaks knowledgeably on this subject in public, they
are marginalized by a variety of means.

http://www.fas.org/irp/eprint/snyder/infowarfare.htm

And if they operate outside the confines of strict US control, they
may even be targeted for assasination.

http://en.wikipedia.org/wiki/Gerald_Bull

Eisenhower worried about the costs and intelligence risks of a large
civilian program in the context of the late 1950s. He felt it would
allow the Russians to steal our missile secrets, as they had stolen
with the help of the Rosenbergs, our nuclear secrets, while we spent
billions on useless space faring infrastructure, the Russians would
use our research results to build wmds that with which to destroy the
United States. So, even while bowing to public enthusiasm for space
travel, he had grave reservations about the wisdom of going down this
path - driven by unwarranted public enthusiasm and greedy aerospace
contractors.

http://space.au.af.mil/histpol.htm
http://mcadams.posc.mu.edu/ike.htm

In the end, the United States in particular, and humanity in general,
has not achieved what it might have this past half century in space
not due to any technical difficulties of achieving wonderous results,
but rather as von Braun described it to Kennedy during his meetings
with him at the White House - we lack the will and the imagination to
do it - and prefer instead to languish in the backwater of history
worried about the difficulties we cannot know,while ignoring the
benefits we will never see.

On Tue, 04 Sep 2007 23:42:54 -0000, wrote:

On Sep 4, 2:25 pm, "Jeff Findley" wrote:
"Jim in Houston" wrote in messagenews:1fmnd3t1jucnva5tofioaprnob2euc2b3j@4ax .com...

On Mon, 03 Sep 2007 00:26:40 -0000, wrote:

A dozen fully resusable vehicles fully interoperable ranging in
payloads from 1/2 ton to 1000 tons - ranging in speeds from suborbital
to solar system escape-
.
Way above my level of understanding, but thank you for trying.

Don't worry. Everything Mookie writes is beyond his level of understanding
as well. This is why he's living in my newsreader's killfile hell.

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)

Jeff has difficulty with reality. He likes to project his
inadequacies onto others. lol.

For the record, I am formally trained in Aeronautical and
Astronautical Engineering, I'm a memberr of The American Institute of
Aeronautics and Astronautics (AIAA) and here's a paper on a modular
approach using Shuttle infrastructure, to creating a low-cost flyback
booster system;
Whoo, Mookie!! If there was ever a case of be careful of what you ask
for, this must be it.
Seriously, thanks for all the info and the links. This fills my
reading list for at least a month! Thanks again.
Jim in Houston.

Contrary to popular opinion RN does not mean Real Nerd!
Teddy Roosevelt's mother said: "Fill what is empty,
empty what is full, and scratch where it itches"

--
Posted via a free Usenet account from http://www.teranews.com

"Jim in Houston" wrote in message
...
On Tue, 04 Sep 2007 23:42:54 -0000, wrote:
Jeff has difficulty with reality. He likes to project his
inadequacies onto others. lol.

For the record, I am formally trained in Aeronautical and
Astronautical Engineering, I'm a memberr of The American Institute of
Aeronautics and Astronautics (AIAA) and here's a paper on a modular
approach using Shuttle infrastructure, to creating a low-cost flyback
booster system;
Whoo, Mookie!! If there was ever a case of be careful of what you ask
for, this must be it.
Seriously, thanks for all the info and the links. This fills my
reading list for at least a month! Thanks again.
Jim in Houston.

Sorry, but anyone with a decent aerospace background knows that such AIAA
papers are a dime a dozen. Dragging out the old *nine* page StarBooster
paper from 2001 doesn't impress me. The devil is in the details and that
paper is decidedly lacking in details.

I earned my B.S. in Aerospace Engineering from Purdue University and was a
member of the AIAA for years after I graduated. That doesn't necessarily
mean much, so I leave it as an exercise to the reader to judge if the papers
Mookie cites are more fluff or substance.

Let me guess, Mookie is still pushing is 7 ET with propellant crossfeed
"design" that he's been pushing for years, right? That will be cheap to
develop and fly, NOT!

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)

On Sep 5, 7:17 am, "Jeff Findley" wrote:
"Jim in Houston" wrote in messagenews:7u3sd3ph7qrptbc2uvuntha3dden8e7c8i@4ax .com...

On Tue, 04 Sep 2007 23:42:54 -0000, wrote:
Jeff has difficulty with reality. He likes to project his
inadequacies onto others. lol.

For the record, I am formally trained in Aeronautical and
Astronautical Engineering, I'm a memberr of The American Institute of
Aeronautics and Astronautics (AIAA) and here's a paper on a modular
approach using Shuttle infrastructure, to creating a low-cost flyback
booster system;
Whoo, Mookie!! If there was ever a case of be careful of what you ask
for, this must be it.
Seriously, thanks for all the info and the links. This fills my
reading list for at least a month! Thanks again.
Jim in Houston.

Sorry,

You are, but what am I? haha.. I just had to say that, lol.

but anyone with a decent aerospace background

And you have one? Interesting, you are impuning my sources without
ever saying why, and implying things about yourself without saying
specifically what your background is... - all very dishonest
techniques.

knows that such AIAA
papers are a dime a dozen.

Really? Are you implying thereby that the editorial and review
policies of the AIAA publications do not meet minimum academic
standards? Are you saying anything specifically about the paper I
cited? No, you are not saying anything of substance - you are merely
mouthing dismissive bull**** while saying as little as possible.

Dragging out the old *nine* page StarBooster

And this is a problem for you because? How about dragging out the
old Tittan flyback booster, or the old vonBraun flyback booster? The
flyback booster was described in the New Horizons study that Hap
Arnold asked for back in 1945. It has been consistently derailed and
marginalized since then. Now because the space shuttle was camel of a
rocket designe by committee, the same folks who marginalized a
properly designed flyback booster are pointing to the shuttle as the
best we can do and we shouldn't even try.

There are two possibilities here;

(1) Aerospace contractors who want throw-away rockets so that they
can reuse their weapons systems factories for space launch - and
continue to steal money from the civilian programs to fund weapons
research they'd rather not go before Congress and discuss.

(2) Missile proliferation folk who don't want space launch to fall
off their plate - a reusable booster would achieve that.

Which camp are you in?

paper from 2001 doesn't impress me.

What would?

The devil is in the details and that

YES!

paper is decidedly lacking in details.

Just like your response. Excepting your response is lacking in even
more details than the paper. Remember, Jim is not an engineer, and
this oft cited Starbooster paper is oft cited for a few good reasons,
its easily understandable by the public, and the data and design is
sold. It asks questions in a way that people can understand. Of
course self-appointed experts such as yourself, ridicule the paper -
and count on lack of public knowledge about winged titan or von
Braun's commentary going as far back as 1948 - without providing any
cogent details yourself.

I earned my B.S. in Aerospace Engineering from Purdue University and was a
member of the AIAA for years after I graduated.

I hosted regional conferences in Ohio when I went back to grad school
at Ohio State. I likely reviewed your paper for inclusion if you
submitted one.

That doesn't necessarily
mean much,

Knowledge is what you make of it. As you said, the details count.

so I leave it as an exercise to the reader to judge

Your desire is to have readers judge me and an oft cited peer reviewed
paper that clearly discusses important aspects of reusable boosters
negatively without really giving us a clear and cogent reason why -
except that you graduated from Purdue and are speaking as the ultimate
authority on usenet. haha..

if the papers
Mookie cites are more fluff or substance.

This is what you want readers to believe - and worse. What was it you
said at the outset, you were warning people not to take me seriously?
lol. This is your goal obviously. Clearly you are unable to provide
any clear and cogent rationale for your conclusions. The one
promoting fluff and no substance is you sir.

Let me guess, Mookie is still pushing is 7 ET with propellant crossfeed
"design" that he's been pushing for years, right? That will be cheap to
develop and fly, NOT!

Any detailed budgetary analysis to back up that opinion Jeffy?

No? I didn't think so.

For the record, the launcher Jeffy speaks of was actually designed
over several years in response to market demand for it.

So, since you brought it up Jeffy, I went to graduate school at Ohio
State and specialized in the design of heavy lift launchers. Before I
got my Phd I started a company to build a launcher back in the 1990s
when Teledesic and Motorola announced their desire to put up large
satellite networks,

Following a meeting with both of the folks in the field at the time I
realized they were counting on economies of scale that weren't there.
That is, they figured if they bought a lot of rockets all at once,
they'd get a discounted price.

They figured wrong because every space rocket built is heavily
subisidized and when you start buying lots of them, you run out of
your subsidy and prices go up.

Now, the government likes this subsidy because it hides the true cost
of space launch from potential acquirers of ICBMs, and it also gives
absolute control to the government of who gets those rockets. Now
strictly speaking this level of control has evolved out of missile
proliferation concerns, and is not a direct consequence. In fact,
when the Challenger accident happened, the Reagan administration wante
the private sector in the US to develop commercial space launch in
direct contravention of missile proliferation concerns. Even so,
power once gained in Washington, is rarely given up freely - not
matter what the cost to the nation.

Anyway, back to the satellite networks of the 90s - The only way to
get prices down I argued was to factor your vehicle development for a
reusable into the price - and continue with a commercial space launch
provider - not a traditional civilian aerospace contractor.

Teledesic said they were prepared to take a risk on the satellite, but
not the risk of satellite multiplied by launcher. So, they pulled
back and said they would wait until launchers caught up with their
vision. They never spent more than $60 million on their system..

Motorola continued on to flight hardware but slowed their launch
schedule and redesigned their satellites and network to accomodate
launch limitations. Meanwhile, development in ground based cell phone
systems wiped out nearly all advantages of the Iridium system by the
time it flew.

Now, before I could offer my launcher for sale I went through the
review and licensing process demanded by the DOT at that time required
for all space launch providers. My design went through a detailed
review at NASA in Huntsville in their space launch group, before I
could offer it to Teledesic or Motorola.

Since that time I have been beset by two groups that seem intent to
marginalize what I have to say;

(1) Space enthusiasts who can be characterized as crazy - folks who
believe variously in anti-gravity, invisibility fields, warp drive,
alien abductions, or some combination of these as the savior of
mankind.

(2) Space 'experts' - such as the present writer - who seek to
discredit me and my designs and ideas without realy saying
specifically what their issue is with me, or promoting bizarre and
outlandish 'solutions' to 'problems' that they make up. A case in
point - I prposed a TSTO-RLV and was attacked by proponents of SSTO-
RLV because I had a staged system. I was attacked by TSTO-RLV
proponents at that time because my Greenspace launcher was inline -
not parallel. I have since increase the size of my launcher and moved
to parallel staging - and I have been attacked for that. haha..

And of course, they work in concert. If I am at a conference and say
good day to someone who does UFO research, that is duly noted by those
who despise such folks - as if saying hello to someone somehow makes
one less of an engineer.

The most interesting was the time I was asked by a very famous MIT
professor to help save a nuclear propulsion system from extinction. I
was the only one who could help. (always beware of that plea! haha)
The NEBA III was a distant cousin of the old Rover program. It was
controlled by folks who worked for the DOE. At their request I used a
NEBA III engine in a reusable automated tug to increase payload
weights for existing launchers to high orbit. (Which undercut the
advantages of a large reusable I wanted to build) - since nuclear
rockets are about twice as efficient as chemical rockets. I figured,
well you can test fly a reusable, and so there is a certainty of
performance the first time you launch a nuclear payload that a throw-
away doesn't have. But of course, associating yourself with anything
nuclear is bad news. haha.. In the end, I ended up at the White
House arguing for privatization of nuclear propulsion and asking
President Clinton for Presidential approval of my right to launch a
nuclear rocket in space - to save this program from extinction.

Well it turns out the program wasn't near extinction, and the whole
thing was a put up job. And at very high levels of government I have
since been known as that crazy guy who wants to buy a nuclear rocket!
haha.. Which marginalized whatever I had to say from there on out.
Even if I was talking about reusable launchers, I'd have to explain my
irrational enthusiasm for privatization of nuclear reactors to be
launched into space carrying hundreds of pounds of weapons grade
plutonium! haha..

Some of my ideas at that time have seen the light of day though with
that work on NEBA III - the idea of using nuclear propulsion and power
systems for large planetary probes to Jupiter and a flight to Pluto
have been adopted albeit slowly, by NASA.

I'll just close by observing that the External Tank for the space
shuttle has a lot going for it as a space launch vehicle - and as a
model for a space launch vehicle. the recent problems with
reformulated foam not withstanding. The advanced thermal protection
systems already developed for the ill fated SSTO program, is perfectly
suited for application to the ET. And a subscale ET isn't that hard
to build to do development work using smaller engine sets..

A stretched self propelled ET - with extra spacer rings between the
LOX and hydrogen tanks is a perfect place for a payload. And with
two SRBs strapped on to the sides, and an aerospike engine and heat
sheild ringing the base - you would have a very interesting launcher
capable of orbiting 50 tons.

Replacing the SRBs with two self propelled ET based LRBs, that, yes,
cross feed propellant into the core booster, just like the ET now
feeds propellants into the orbiter, to operate as two chemical stages
- capable of orbiting 150 tons

And finally adding four more self propelled ETs to create a 3-stage
system - from 7 elements

From above,

(1)(2)
(3)(4)(5)
(6)(7)

Where 1 and 6 feed propellant to 3
Where 2 and 7 feed propellant to 5
Where 3 and 5 feed propellant to 4

And 4 is a stretched ET carrying 500 tons of payload!!
Why do this?

Because at launch, 1,2,6,7 drain first - as a first stage
Then, 3 and 4 drain second - as a second stage
And 4 continues to orbit - as a third stage

With the ET sized airframe - and five RS68 rocket engine pumpsets -
built into an aerospike nozzle ringing the base each ET - with the
base of the elements spread relative to the top, so that there is a
slight dihedral - avoiding exhaust interference and improving flight
dynamics - the way pronation on tires improve steering.

Anyway..

One could take the ET airframe and rework it into a resuable flight
element and with it build a substantial lift capacity very quickly -
and cheaply.

50 tons - 1 element + srb
150 tons - 3 elements
500 tons - 7 elements

The 'smaller' vehicle could orbit 20 satellites at a time in a single
orbital plane - which would make it ideally suited for deploying
networks of 300 to 900 satellites.

A satellite network has the capacity to revolutionize communications
on Earth. A phased array antenna system on each satellite, controlled
by GPS signals, allow each moving satellite to paint millions of
stationary viritual broadband cells across the Earth to communicate
with any IEEE803 complaint device. Laser beams communicate at tens of
terabits per second between satellites and provide a global backbone.
Each satellite acts like a router in the network. 50 billion
broadband channels are available - and USNews and World Report in the
1990s reported that such a system could capture $80 to $90 billion per
year!! At $100 million per sattellite and 400 satellites - that's $40
billion.
..
A launch provider that received 33% of the revenues from such a system
(which has no recurring costs to speak of and a 10 to 20 year life
span) receiving he $3 billion out of pocket costs against for vehicle
development as a draw against its 33% stake in a satellite net - would
be in the catbird seat as far as rocket development was concerned. It
would raise its $3 billion - build 3 modified self-powere ETs - and 6
advanced SRBs - and launch the fleet of 400 satellites in 20
launches. Then sit back and collect $14 billion per year for 10 to 20
years. And use that money to design bigger satellite networks and
bigger launchers to serve them.

Leading ultimately to powersats.. and a global power network.

lol.

http://en.wikipedia.org/wiki/Solar_power_satellite

The world spend $2 trillion per year on energy today, and that is
growing by 4% per year. In places like China and India growth rates
are double digit! The world uses energy at a rate of 10 trillion
watts.

Sunlight in space delivers 100,000 trillion watts
Sunlight on earth delivers 50,000 trillion watts usable
Wind, tides, currents, rivers - deliver 330 trillion watts
Photosynthesis delives 40 trillion watts
Human farms deliver 2 trillion watts

You can see the advantage of using space based power - the fact you
have no clouds no night - is a plus.

On Aug 24, 8:46 am, Aaron Lawrence
wrote:
Has anyone ever flown flyback boosters on any vehicle?

--
aaronl at consultant dot com
For every expert, there is an equal and
opposite expert. - Arthur C. Clarke

On Aug 24, 8:46 am, Aaron Lawrence
wrote:
Has anyone ever flown flyback boosters on any vehicle?

--
aaronl at consultant dot com
For every expert, there is an equal and
opposite expert. - Arthur C. Clarke

Did Arthur Clarke actually say that? haha..

There have been lots of re-entry vehicles flown - and studying the
requirements for them tells you a little bit about flyback booster
designs.

http://en.wikipedia.org/wiki/Atmospheric_reentry
http://en.wikipedia.org/wiki/Thermal_barrier_coating
http://en.wikipedia.org/wiki/Superalloy
http://www.usace.army.mil/publicatio...2-3401/c-2.pdf

The big problem with flyback boosters is their rather large area per
unit weight - this makes their drag very high. This is a good thing
in that you can reach subsonic speeds rather easily.. but since you
want your structural fraction at an absolute minimum - you don't want
to overstress the balloon like tank. So most designs pressurize the
tank to stabilize it during re-entry - and have a pretty high lift/
drag ratio to stay in the upper atmosphere - low density -to reduce
gee forces during re-entry to low levels. A two gee deceleration
profile appears possible from orbit with lift/drag ratios of 1.6 or
so.

Of course, if you slow from speeds less than orbital - then conditions
are improved.

A simple biconic system with scissor wings - like that being flown on
small munitions today -

http://stinet.dtic.mil/cgi-bin/GetTR...c=GetTRDoc.pdf

could be adapted to a very flexible flyback booster of reasonable
structural fraction.

The External Tank on the space shuttle

http://en.wikipedia.org/wiki/Space_S..._external_tank

is an interesting prototype for a reusable stage...

Consider, that if you remove the foam, and replace that with a more
permanent thermal protection system - as described above, and change
slightly the profile of the nose and tail section (we're talking new
construction here and using the ET as a starting point) - we can
create a biconic system with a 1.6 lift to drag ratio during the re-
entry phase of flight. Then, equip it with fold-away scissor wings
near the CG of the empty ET - to increase its Lift/Drag to about 2.5
to 3.0 in subsonic flight.

Empty Weight: 58,500 lb (26,559 kg)
Gross Liftoff Weight: 1.680 million lb (762,136 kg)

So, we're talking the ET empty is 26.6 metric tons and full 762.1
metric tons - so it carries about 735.5 metrict tons of propellant.

Remove the foam thermal protection system, and replace with a more
permanent thermal protection system, and you increase the tank mass by
about 20 metric tons. Add five RS-68 pumpsets and an annular
aerospike nozzle - at the base adds another 33 tons - or just 5 RS-68
engines attached to the base of an ET (with flared conical tail
section)

http://en.wikipedia.org/wiki/RS-68_(rocket_engine)
http://upload.wikimedia.org/wikipedi...-Aerospike.jpg

Burns a 1:6 liquid hydrogen / liquid oxygen ratio.
The specific impulse is 410 s (4 kN·s/kg) in a vacuum
and 365 s at sea level at maximum thrust.
The engine's mass is 14,560 lb (6,600 kg) and has a thrust to weight
ratio of 51.2.
The RS-68 is gimbaled hydraulically and is capable of throttling from
57% to 102% thrust

Each one at full-thrust at lift off produces 301 metric tons of
thrust. So, five engines produce 1,505 tons at lift-off - and are
lifting about 810 metric tons of vehicle + payload.

What would such a system's final velocity be?

Well, the rocket equation tells us...

http://en.wikipedia.org/wiki/Tsiolko...ocket_equation

Ve = Isp"g0 = 410 sec x 9.82 m/s/s = 4,062.2 m/s
M0 = 810
M1 = 75

Vf = 9,666.2 m/s (ideal)

Ideal because about 2.2 km/sec is subtracted due to air drag and
gravity losses during ascent. These may be reduced if higher gees -
up to 5 - can be sustained by the system during ascent. But this has
an impact on structural fraction as well.

A throttable system - like the RS-68 - permits one to maintain
controlled gee forces while the system is expending propellant - .

A target M1 of 74 tons, and a Vf of 9.2 km/sec (ideal) would allow 10
metric tons to be placed on orbit with a SSTO that was built around an
ET sized system just described.

Now add another ET to the first one, and feed propellant from one to
the other - just like the ET feeds propellant to the Space Shuttle,
leaving the second stage - full when the first stage is emptied - and
what do you get?

Well, one is 810 tons and the other 810 plus payload...

Ve = 4.0 km/sec
M0 = 1620
M1 = 810

Vf = 2.77 km/sec

for the first stage, and 9.6 km/sec for the second stage...as before -
for a total delta vee of the entire vehicl of 12.37 km/sec which
allows you to project payloads to the moon on a lunar free return
trajectory ... and recover both sections.

Subtracting 2.7 km/sec from 9.2 km/sec - needed after losses to attain
orbit - obtains 6.5 km/sec. Dividing this figure by four and taking
the exponent obtains a mass ratio of 5.1 - which starting with 810
tons obtains a structure + payload of 158.8 tons - subtracting 74 tons
- obtains 84.8 tons payload.

NOTE these are preliminary boe calculations. Actual calculations use
calculus of variations - and will permit higher payloads. Numerical
methods runnings detailed codes will extract even more accurate
performance estimates - allowing higher figures. Variations will
allow higher figures as well - for example, adding an SRB pair to the
core booster - and throttling it way back before separation - or
starting it mid-flight, or taking the parallel stage that separates at
2.5 km/sec and adjusting its thermal protection to save a few tons of
weight and so forth..

Three elements - a core surrounding by two outer liquid boosters -
built around the same element - 3 x 810 = 2,420 at launch, and the
'second' stage is 810 - so a mass ratio of 3:1 - the natural log of 3
is 1.1 multiply by 4.0 km/sec and obtain - 4.35 km/sec - subtract this
from 9.2 km/sec and obtain 4.85 - divide by 4 and obtain a velocity
ratio of 1.2125 - take the exponent and obtain a mass ratio of 3.36 -
and divide that into 810 - and obtain 241. (Calculus of variations
would allow you to figure the optimal trade off of adding payload and
subtracting propellant to the system of equations you'd set up to get
a higher and better estimate - but this procedure is a good back of
envelope estimate - low end - of performance)

So, we have an interesting array of cross-fed tanks...

1 ET sized tank - 10 tons leo
2 ET sized tank - 85 tons leo
3 ET sized tank - 240 tons leo

(the last figure is 3x that of Apollo's Saturn V rocket!)

We can continue with this sort of estimatint procedure;

Four ET - with one core and three outer tanks, spaced 120 degrees
apart around the core - set up to feed two - into two - for a first
stage - then one into one for a second stage, and the core as a third
stage;

First Stage

m0 = 810 x 4 = 3,240
m1 = 810 x 2 = 1,610
m0/m1 = 2
ln(2) = 0.6931
Ve = 4.0 km/sec
Vf = Ve*0.6931 = 2.77 km/sec

Second Stage

m0 = 810 x 2 = 1,610
m1 = 810
m0/m1 = 2
ln(2) = 0.6931
Ve = 4.0 km/sec
Vf = Ve * 0.6931 = 2.77 km/sec

Third stage

Vf(target) = 9.20 km/sec
Vf(revised) = 9.20 km/sec - 2.77 - 2.77 = 3.66 km/sec
Vf/Ve = 3.66 km/sec / 4.00 km/sec = 0.9150
m0/m1 = exp(Vf/Ve) = exp(0.9150) = 2.497
m0 = 810
m1 = m0/(m0/m1) = 324.4
payload = m1 - structure = 324.4 - 74 = 250.4 tons


4 ET - 250 tons

five ETs - a core with four peripheral boosters 90 degrees apart -
two, then two then the core forming three stages...

Six - a core with five peripheral boosters - 72 degrees apart - three
then two then one
Seven - a core sith six peripheral boosters - 60 degrees apart - four
then two then one

A detailed analyis shows that up to 500 tons can be placed into orbit
using this sort of system...

Now on re-entry... You have 74 tons of structure - that has a body
size of;

Length: 153.8 ft (46.9 m)
Diameter: 27.6 ft (8.4 m)

A volume of a cylinder this size is 2600 cubic meters approximately -
a nose cone subtracts from the total, and a flared tail adds to it...
so, lets say 2,500 cubic meters as an estimate. The mass is 75 tons
lets say - just to make the numbers easy, so we're talking about a
density of 75 tons over 2500 cubic meters - or 3/100 - a density
about 1/33rd that of water!!!!

The ballistic coefficient is;

http://en.wikipedia.org/wiki/Ballistic_coefficient

C = d x L / Cd

d = 0.03
L = 46.9
Cd = 0.6

C = 0.03 * 46.9 / 0.6 = 2.345

This is a low figure so heating need not be that bad but acceleration
would - unless lift to drag is low enough to loiter in the upper
atmosphere to control deceleration... and limit structural
requirements... and thermal requirements...

Once subsonic speeds were reached - and at lower altitudes - in the
troposphere -altitudes airliners can reach - 10 km or so - the scissor
wings pop out and the shaped ET type tank increases its L/D ratio to
2.5 to 3.0 which means that the drag of the vehicle at a speed to
maintain 75 tons of lift - will be around 25 to 30 tons of drag...
this is easily handled by a 747 or 737 aircraft.

http://en.wikipedia.org/wiki/Corona_%28satellite%29
http://upload.wikimedia.org/wikipedi..._recovery..jpg
http://upload.wikimedia.org/wikipedi...v_film_pod.jpg

But instead of snagging it and bringing it on board - the 737 airliner
will capture a tow line the booster will drop - and tow it the way
they towed lifting bodies back to the airfield in the old days;

http://www.centennialofflight.gov/es...s/Tech29G3.jpg

Using GPS receives and bluetooth type communications between the
booster and recovery aircraft will allow the 737 to loiter near the
recovery point, dash in and snag the booster while in slow speed
flight - with a sink angle of 20 degrees - and an altitude of 30 km -
dropping to 10 km - allows a cross range of about 90 km - at around
200 kph. The 737 can travel at 900 kph - and so can close on the
booster in the 17 minutes it reaches 10 km altitude (32,000 ft) - and
you have a window of opportunity of about 6 minutes to execute capture
and tow of the booster before it glides into the ocean or ground...

So, you'd be getting flight data telemetered to the recovery aircraft,
and the spacecraft - so that you'd be within 10 km of the terminal
point - and while the booster sank from 30 km to 10 km - you'd effect
closure - and when you got within 500 m of the booster you'd slow, the
booster would drop its snag line - and the aircraft would drop its
pickup line, and you'd capture the booster for towing back to the
launch center... at about 200 kph rising to maybe 400 kph - by
pulling in the scissor wings a little...

So, that's how you'd do it.

Landing gear weight - forgot that! haha..

http://www.aoe.vt.edu/~mason/Mason_f/M96SC08.pdf

Well, this is a special case, the 'vehicle' is empty -and masses 75
metric tons that way - and 810 metric tons full! - that's 165,000
pounds - about the size of a DC9 landing weight - according to
parametic models -this is about 3% of the flight weight - so we're
talking 2.25 metric tons for landing gear weight - which is included
in the totals already mentioned -

The 10 ton payload is inserted in the intertank space between the lox
and liquid hydrogen tank. This section can be extended by inserting
'rings' there 'stretching' the airframe.. which could change this -
causing us to beef up the landing gear. A 250 ton payload - having a
density of 100 kg per cubic meter - the same as the 747 large cargo
freighter

http://en.wikipedia.org/wiki/Boeing_...argo_Freighter

184 tons useful payload - 1,840 cubic meters..

would have a volume of 2,500 cubic meters - and with a vehicle
diameter of 8.4 meters - a payload section 45.1 meters long would have
the same volume to weight ratio as a modern cargo plane...doubling the
length of the core booster - a 500 metric ton payload section would
be 90.2 meters long... tripling the length of the core booster...
likely adding another 50 tons and 100 tons respectively to the
structural weight.. subtracting from the payload worst case - prior
to the application of calculus of variation or numerical methods.

Awesome performance though, with off-the-shelf technologies.

Estimating vehicle development costs, based on costs of comparable
programs - this program of inter-operable boosters - to provide a
variety of launch capacities - from 10 tons to 500 tons to LEO - would
cost around $6 billion to develop in a four year period. An
additional $10 billion would result in a fleet of 14 launch elements
that could operate in a variety of modes - everwhere from launching
500 tons as a 7 element 3 stage system every month - to launching 10
tons on an SSTO every 2 days.

This includes a fleet of 10 recovery aircraft - 737s - outfitted to
snag boosters downrange - and fly airframes around for service and so
forth.. (and deliver parts and personnell)

Each airframe would be good for 9,300 flight cycles (same as the
Concorde) - the engine sets would be good for 200 flight cycles - so
45 engine change outs would be needed - about $100 million per set -so
that's . $4.5 billion for 9,300 flights - $500,000 per flight - $713
million per airframe, $77,000 per flight for airframe costs add in
other recurring costs - and you have about $2 million per launch per
element. 7 elements - $14 million per launch - 500 tons - $28 per
kg. 1 element - $2 million - 10 tons - $200 per kg.

A 2,500 kg satellite at $250,000 - would be interesting - and quite
profitable.
A 500 kg payload per passenger - at $50,000 - would be interesting -
and equally profitable

A satellite network with 600 satellites communicating with one another
to make of the world a single wireless hotspot. Large phased array
antennae - on each satellite paint millions of stationary doppler
corrected virtual cells across the surface of the Earth- controlled by
GPS signals. The virtual cells communicate with billions of IEEE803
compliant devices. The satellites communicate with one another using
open optical laser communications

http://lasers.jpl.nasa.gov/

Creating 50 billion channel wifi network that earns between $90
billion and $120billion per year. The satellites at $50 million each
would cost $30 billion - and the launcher system - described here -
would cost $16 billion. The costs of the system would be nil to
operate it for 20 to 30 years on orbit. The system would cost 25% of
the first year's income to put up.

An aerospace company that agreed to build this sort of launcher system
and satellite network for a 25% stake in a global hotspot and borrowed
from the investor group the $46 billion construction costs of the
network - would position itself to not only have a very low cost
launcher system, but would earn $22.5 billion to $30.0 billion per
year in free cash flow - without having to do additional launcher
work. This would be sufficient to upgrade the launcher system to
include manned vehicles and expand the marketplace for space faring.
This includes space hotel, space tourism, lunar settlements, mars
expeditios, mars settlements, asteroidal survey, asteroidal capture
and development, deep space robotic network, powersats, laser
propulsion, space colonies, personal space station, personal
spacecraft, etc.