4.0 Earth based facilities |
The initial financial support of this project is based on
two industries - hydroponics and robotics. These two industries
can be initiated in any country around the world that wishes to
do so. The hydroponics industry requires a number of research
facilities whose job is to develop a detailed plan for the growing
of each of the crops judged to be appropriate. The building of
these facilities can begin immediately using current hydroponic
technology.
The android business clearly requires a few years of lead time
to develop the androids. Most of the hardware necessary to build
the androids is already available - such as color TV cameras for
eyes, microphones and speech recognition computer software for
hearing, speech synthesizers for voice output, pressure sensitive
materials for "skin", composits for "bones", and so on. The only
hard part is the brain. This will require a significant effort in
artificial intelligence both for image recognition and thinking.
It will also require a greater level of intercomputer communication
than is common today. We are confident that prototypes could be
produced within three years given a modest investment of say five
million dollars.
Space and nuclear fusion are the two industries which we plan
to develop in the future. Nuclear fusion will supply the power to
run our civilization in the twenty-first century and beyond. The
surface of the moon contains a resource called helium-3 which will
be used to generate power in fusion reactors. Since it is on the
moon, we must go there to get it. (We are aware that there are
sources of helium-3 which are of much higher concentration, namely,
Jupiter, Saturn, Uranus, and Nepture, but there are many reasons
why these sources are less attractive than the moon. Among them
are: (1) the very high cost of sending a large facility to Uranus,
(2) the delay of many years while the automated facility mines and
returns the helium-3, and (3) the fact that you have no lunar base
when the helium-3 is returned.)
In order to develop space we first need to find cheaper ways
to lift payloads into space.
4.1 The cost of payload in orbit So far rockets have lifted everything that has been put into space. The cost of lifting payloads is of paramount concern to any company that wishes to make a profit in space. Not surprisingly it is very difficult to get genuine numbers where the cost of launch vehicles is concerned. Consider the following: * Table 4.1-1 Costs of various boosters
Booster LEO cost GEO cost Source
$/kg $/kg
Shuttle 14,960 [28, p.50] Newsweek
Titan 4 11,220 "
Delta 7,205 "
Proton 1,650 "
Energia 660 "
Titan 34D/IUS 68,200 [97, p.132] OTA Atlas/Centaur 55,000 " Delta 52,800 " Ariane 3 44,000 " Ariane 4 41,800 " Titan 34D/TOS 37,400 " Shuttle 39,900 * Author (NASA data) Titan 4 35,133 [AW 58, p.79] GAO est. Long March 3 7,143 * 35,714 [AA 6, p.54] Titan 34D 4,333 [AA 1, p.6] Ariane 4 3,970 * [97, p.131] OTA Shuttle-C 3,446 [AW 63, p.18-20] OTA est. Energia 2,727 [AA 4, p.34] Proton 2,381 * Space Commerce Corp. . Which are the real numbers? (*) In general the higher costs are more believable. Art Dula of Space Commerce Corp quoted the Soviet Proton rocket at $50 million per flight. That works out to $2,381 per kilogram of payload. The Ariane 4 was quoted at $54 million per flight by the OTA in [97, p.131] which is in close agreement with a figure of $50 million seen elsewhere. This works out to $3,970 per kilogram. The Long March 3 was priced at $25 million according to Ad Astra, [AA 6, p.54]. That information combined with data obtained from the embassy of the People's Republic of China about their launchers yields a figure of $7,143 per kilogram for LEO and $35,714 per kilogram for GEO. Everyone knows that NASA is not charging space shuttle customers the full cost for placing their payloads in orbit, (neither is Arianespace, they charge 2/3 of cost [97, p.131]) but using NASA's own data it is possible to calculate how much the shuttle is costing the US taxpayer - and it is astronomical. It works out to $39,898 per kilogram in current dollars and more in 1990 dollars. 4.2 Alternatives to rockets for launching payloads from earth Entrenched special interests have succeeded in inhibiting the
development of cheaper alternatives to rockets. Many other and
cheaper alternatives exist if only they received enough funding to
allow them to succeed. Below we list some of these alternatives.
In all of the following, the costs given refer only to the
launch costs. Costs of satellites and their development are an
entirely different subject. No costs are included for insurance
or bureaucratic red tape (courtesy of the government) either.
4.2.1 High Altitude Research Project (HARP) William Lowther has written a fascinating book called "Arms
and the Man: Dr. Gerald Bull, Iraq, and the Supergun", [Ref 117],
which tells the story of Gerald Vincent Bull and the guns he designed
over the years. The following story is excerpted from Lowther's
book.
The great passion of Gerald Bull's life was to build a gun
which would fire satellites into orbit. His first real chance to
work on that project came in the early 1960s when he was a professor
at McGill University in Montreal. The High Altitude Research Project
(HARP) was a joint project of the Canadian government and the
US Army. The US Army supplied the guns to be used in the experiments.
The largest was a 40-centimeter (16 inch) gun built for the US Navy
in 1921. That gun was 21 meters long and weighed 125 metric tons
[117, p.73]. A spare 40-centimeter barrel was included and also a
10-centimeter gun for preliminary experiments. The big gun could fire
a 180 kg projectile at a velocity of 1800 meters per second [117,
p.85]. The gun was set up on the south east coast of Barbados at
Seawell Airport (13,04,28 N, 59,28,37 W) in 1962 and the project got
under way [127, p.157].
HARP was always in trouble. Bull had made lots of enemies in the
Canadian government who were trying to kill his project. But Bull
wasn't the only one in trouble. The US Army had problems too. There
was a squeeze play at the Pentagon which forced the Army out of the
satellite business. So the Army was funding research for sub-orbital
trajectories while the Canadian government was funding the satellite
part - on paper anyway. The Pentagon was really interested in the gun
for use as a cheap anti-missle point-defense system.
On January 21,1963 Bull's second shot reached 26 kilometers
in altitude. On June 18,1963 one of Bull's 170 kg shells set an
altitude record of 92 kilometers. In spite of the horrific
accelerations that the shells were subject to "ways had been found to
fire delicate guages and timing devices without damage" [117, p.83].
In 1965, Bull had a 16 meter extension attached to the gun and
with that he was able to reach 150 kilometers in altitude. Eventually
the Army set up another 40-centimeter gun and research facility
at its Yuma, Arizona proving grounds to protect themselves against
the possibility of the Canadian government pulling out of the
project. The night of November 18,1966, the Yuma gun fired one of
Bull's projectiles to a height of 180 kilometers [117, p.93]. The
Canadian government halted funding June 30,1967 after having invested
a total of $4.3 million. The US Army had invested somewhat more,
but the project total was less than $10 million. The shells cost
$3,000 to $5,000 each.
Gerald Bull and Charles Murphy wrote a book called "Paris Kanonen
- the Paris Guns and Project HARP" [Ref 127] which gives copious data
on long large artillery. It contains many pictures of the Barbados
installation and the guns and projectiles used.
4.2.2 Hydrogen gas gun Lawrence Livermore National Laboratory (LLNL) is working on
a hydrogen gas gun as a possible alternative to current launch
systems. In an article by B.W. Henderson in Aviation Week and
Space Technology [AW 24, p.78-9], J.W. Hunter of LLNL revealed
some of the details of this scheme.
The gun's major components are two large tubes: the pumping
tube which is about 800 meters long and 3.6 meters in diameter
and the launching tube which is about 700 meters long and 1 meter
in diameter. The two tubes are joined end to end by a diaphragm.
Inside the pumping tube is a 400 ton piston which is positioned
about 700 meters from the diaphragm. The projectile to be fired from
the gun rests inside the launching tube close to the diaphragm.
In order to fire the gun, the following sequence of events
occurs: (1) A combustable gas is pumped into the first 100 meters
of the pumping tube behind the piston, (2) hydrogen is pumped into
the 700 meters of the pumping tube in front of the piston, (3) the
launching tube is evacuated beyond the projectile, (4) the
combustable gas is ignited which causes the piston to be driven
down the pumping tube thus compressing the hydrogen, (5) the
compressed hydrogen gas ruptures the diaphragm which separates
the two tubes, (6) the hydrogen then expands against the projectile
in the launch tube causing it to accelerate along the launching
tube, and finally, (7) just as the projectile reaches the end of
the tube an iris opens to allow the projectile to exit the tube at
high speed. Additional particulars include the following. The whole
gun would be about 1500 meters long and would be built up the
side of a mountain at an elevation of 6000 feet and at an angle of
25 degrees to the surface of the earth. The projectiles would
weigh about 2000 kilograms each and would exit the gun at a velocity
of 6 kilometers per second.
Each projectile will follow a ballistic trajectory and
therefore will not go into orbit unless an on board rocket is used
to circularize its orbit and increase its horizontal velocity
component. In order to keep costs down a cheap solid propellant
will be used (we have assumed a specific impulse of 250). Using
the above data we have calculated that the projectiles will reach
an altitude of about 240 kilometers with a horizontal velocity
of about 4532 meters per second. At that altitude an additional
2830 meters per second of velocity are required to attain orbit
assuming about 400 meters per second due to the earth's rotation.
This implies a mass ratio of 3.17 between the initial mass of the
rocket which we assume to be 1900 kg at that time and the final
mass of 600 kg (consisting of the payload, the rocket engine and
the rocket casing which is now empty).
The projectile mass would be divided up as follows:
* Solid rocket propellant 1300 kg
Payload 340 kg
Rocket casing & engine 260 kg
Nose cone & sabot 100 kg
--------
2000 kg
.
The cost of $600 per kg of payload is based upon Hunter's
estimates of 3000 projectile launches per year for 10 years.
This would put 10,000 metric tons in orbit assuming a loss
rate of 2%. (3000 * 10 * 340 = 10,200 MT - 2% = 10,000 MT)
Hunter estimates a total 10 year cost breakdown as follows:
* Research and build gun $ 2.0 B
30,000 projectiles $ 3.7 B
Operating costs for 10 yrs $ 0.3 B
-------
$ 6.0 B
.
The cost per payload kilogram would then be:
* $ 6 B / 10,000 MT = $600/kg
.
The incremental cost per projectile would be:
* $ 3.7 B / 30,000 = $123,333 per projectile
$ 0.3 B / 30,000 = $ 10,000 per launch
--------
$133,333 per projectile launch
.
The cost per kilogram of payload would then be:
* $133,333 / 340 kg = $392/kg
.
There are some very serious questions about whether this
system will work and whether it is cheap enough to compete
against alternative launch methods (other than the space
shuttle which is arguably the most expensive of all launch
methods). The claimed working pressure of the piston is
80,000 psi. That is a very high pressure for a pneumatic
piston. Imagine the technical problems of building a 400
ton piston which is 3.6 meters in diameter with a tolerance
of a ten thousandth of an inch. And the same goes for the tube,
all 700 meters of it. What about the frictional forces as the
piston moves in the tube? Will they damage either the piston
or the tube?
4.2.3 Two stage hydrogen gas gun In order to overcome some of deficiencies of the LLNL gun,
John Hunter et al. have proposed a two stage hydrogen gas gun
which would give the payload two pushes instead of just one. This
gun could launch 2000 kilograms at 7.1 kilometers per second and
would cost about $500 million to build [122, p.18].
We have a program which calculates the various parameters
of gun launched projectiles. The following table was prepared
with this program. It shows the approximate cost of rocket
assisted projectiles fired from a two stage hydrogen gas gun in terms
of both total cost and cost per kilogram of payload. One can see
from the table that the cost is extremely sensitive to the specific
impulse (Isp) of the propellant.
* Table 4.2.3-1 Cost of gun launched projectiles
Mass Launch Isp mass Payload ( % ) Cost Cost
(kg) angle (s) ratio (kg) 1000s per kg
1600 30 250 2.40 574.4 35.9 $ 84.6 $ 147
275 2.21 635.1 39.7 $ 80.2 $ 126
460 1.61 934.5 58.4 $ 58.4 $ 62
1800 29 250 2.28 690.3 38.3 $ 90.7 $ 131
275 2.11 757.8 42.1 $ 85.8 $ 113
460 1.56 1086.6 60.4 $ 61.9 $ 57
2000 28 250 2.18 810.1 40.5 $ 96.6 $ 119
275 2.03 884.2 44.2 $ 91.2 $ 103
460 1.53 1241.1 62.0 $ 65.2 $ 53
2200 27 250 2.10 933.1 42.4 $102.1 $ 109
275 1.96 1013.5 46.1 $ 96.3 $ 95
460 1.50 1397.5 63.5 $ 68.4 $ 49
Assumptions:
1. Muzzle velocity of 7100 meters per second.
2. Launch altitude is 1500 meters.
3. Launch latitude is 5 degrees or less.
4. Single stage booster
5. Tanks and engines weigh 10% of the propellant
6. Fuel cost = $20 per kilogram
7. Tanks and engines cost = $600 per kilogram
8. Additional launch cost of $10,000 per shot
Column
1. Mass of projectile in kilograms
2. Optimal launch angle in degrees
3. Isp - specific impulse of rocket propellant carried
4. Mass ratio of projectile and propellant
5. Weight of payload in kilograms
6. Percentage of payload in projectile
7. Cost of each shot - no amortization of gun cost
8. Cost per kilogram of payload.
4.2.4 The Boeing gas gun The Boeing Company is working on an improved version of a
hydrogen gas gun too. The operation of the gun is similar to the
Livermore gun but has been improved in several ways. First, the
pumping cylinder will run down an incline so that the methane
explosion behind the cylinder will not be necessary. Second, high
pressure will be maintained on the projectile for a longer period
by opening the access valve before the pumping piston reaches the
end of the pumping cyclinder. In the Livermore design the projectile
receives only one push and thus the gas pressure falls off
substantially as the projectile moves down the launch cylinder. In
the Boeing design the pumping cylinder will still be compressing the
gas while the projectile is moving down the launch cylinder. The
pressure of the gas between the piston and the projectile can be
controlled to stop the piston and launch the projectile at the same
time. Since there will be no explosion, that part of the pumping
cylinder need not be nearly as strong as the corresponding portion
of the Livermore gun. Thus it will be cheaper.
Boeing plans to launch a series of projectiles which contain
primarily propellant and small boosters. After each projectile is
launched it will rendezvous with the others and will join together
to assemble a multi-engined booster. Finally the actual satellite
will be launched and will be attached to the booster. Under control
from the ground, the booster will be ignited and will lift the
satellite to GEO.
4.2.5 Electromagnetic "coil gun" Sandia National Laboratories are developing an electromagnetic
"coil gun" which could be an inexpensive alternative to current
launch systems. In a report published by Sandia in October 1991
the project is described in great detail [Ref 107].
The full scale gun would be 960 meters long and about
0.720 meters in diameter. It would be built on the side of a
convenient mountain and would slope upward at an angle of about
25 degrees. This gun is an example of what has been referred to
elsewhere in this book as an electromagnetic projectile launcher
or EMPL. Electromagnetic fields which are produced by current
flowing through coils of wire are used to accelerate projectiles
to high velocities. The velocities anticipated for this gun are
about 6 kilometers per second. In this gun the projectiles
have the following major components:
* Component Mass(kg) Purpose
Armature 600 accelerate the projectile
Aeroshell 370 protect the projectile as it passes
through the atmosphere
Rocket engine 40 to boost the payload into orbit
Propellant 610 fuel for the rocket
Tankage 100 framework to hold the propellant
and the engine
Payload 100 what is to be placed in orbit
----
1820 kg
.
Since this gun is basically a ballistic launcher, the
projectiles will fall back to earth unless on board rockets
are used to adjust the trajectories of the projectiles and to
increase their velocities by the proper amounts to permit the
projectiles to assume standard orbits.
* Cost estimates are as follows [107, p.5]. Item Cost ($ B)
Research and development $ 0.41
Full-scale gun and launch facility $ 2.30
4000 projectiles $ 1.88
Operating costs for 7 years $ 0.35
----
$ 4.94
.
The cost per kilogram of payload would then be:
* $ 4.94 B / ( 4000 * 100 ) = $12,350
.
The incremental cost would be approximately:
* $ 1.88 B / ( 4000 * 100 ) = $ 4,700
+ $ 0.35 B / ( 4000 * 100 ) = $ 875
-------
$ 5,575 per kilogram
.
M. Bill Cowan, manager of Sandia's Advanced Energy Conversion
Systems Department told me in a brief phone interview that the
costs could be reduced significantly. He said the above estimates
were based on available (and very expensive) equipment used by
the DOD for ballistic missiles. All such components are mil-spec
and therefore cost about twice as much as need be. Cowan stated
that the costs could come down to $200 - $500 per pound or
$440 - $1100 per kilogram.
4.2.6 Railguns The Strategic Defence Initiative Organization (SDIO) has
invested millions of dollars in railgun research over the past
few years. Aviation Week [AW 15, p.42] of 8/22/88
reported SDIO funding at $11 million in 1987 and $12 million in
1988. Most of their work has been done at Eglin AFB in Florida.
Eglin has 16 railguns in six bays which point out over the
Gulf of Mexico [AW 15, p.41].
The largest gun at Eglin is 5 meters long and has a 5
centimeter square bore [AW 16, p.71]. This gun has fired 150
gram projectiles at speeds of up to 2 kilometers per second.
It is clear that these guns are orders of magnitude too small
to be of any use in launching payloads into low earth orbit.
They have other problems too. "A major problem with rail
guns is minimizing wear on the rails and insulators caused
by the high currents and plasmas that present an 'arc welder'
environment" [AW 16, p.71]. This necessitates discarding the
barrel after only a small number of shots. In addition "the
technology has run into an unexpected barrier at 6 kilometers
per second" [AW 46, p.51].
This barrier may not be that unexpected. In a report by
William Salisbury published in 1958 [Ref 121], the following
statement regarding railguns appeared on the first page -
"sliding contact or rail guns [have] produced somewhat better
velocities than we have achieved, but experiments in a vacuum
[have] led us to the conclusion that a fundamental limitation
to about four to six thousand feet per second exists in the
sliding contact." Salisbury goes on to say that "such contacts
cease to function when the relative velocity of the contacting
elements exceed the shock wave velocity in the arc ion gas at
the contact." In short, they won't work!
The interested reader may wish to review the following
additional articles in Aviation Week and Space Technology:
[AW 2, p.92], [AW 9, p.28-9], [AW 14, p.29]. See also
[106] Aerospace and Defence Science of Nov/Dec 1990.
4.2.7 Scram gun The University of Washington is working on a projectile
accelerator device which works like a ramjet and which may
be a candidate for launching small payloads into low earth
orbit. In an article by B.W. Henderson in Aviation Week and
Space Technology [AW 46, p.50-1], the scram gun was described
as follows.
The gun consists of a rather standard barrel filled with
a fuel/oxidizer mixture at 10-30 atmospheres. The projectile
fits loosely inside and is conical at both ends. The fuel is
ignited behind the projectile. This causes the projectile to
move forward through the fuel which compresses the mixture
around the projectile as in a ramjet. The fuel then ignites
behind the projectile accelerating it more.
Professor A. Hertzberg, who originated the scram accelerator
concept in 1983, and A.P. Bruckner and others at the University
have built an accelerator 40 feet long and 1.5 inches in diameter.
Their accelerator has fired 70 gram projectiles at velocities
of up to 2.6 kilometers per second.
It is clear that this type of gun will have a lower peak
acceleration than the hydrogen gas gun described above; however,
it may have a higher average acceleration because the hydrogen
gas gun provides only one push on the projectile while the
scram gun provides continous acceleration. This implies that
the scram gun will be much longer. Indeed preliminary
specifications call for a launch tube 5 kilometers long and 1
meter in diameter. It would slope up a mountain as in the
hydrogen gas gun and the coil gun. It would fire 1 ton
projectiles of which about 50% would be payload [AW 46, p.51].
A large scale gun of this type should be easy to build.
The real worry is will it work at speeds in the range of 6 - 10
kilometers per second which are required for orbiting payloads.
The problem is the heating of the nosecone of the projectile
as it rams through the fuel/oxidizer mixture. If the nosecone
becomes hot enough to ignite the mixture in front of the
projectile, it won't work.
Estimates of the cost per kilogram of payload are in the
range of $330 [AW 46, p.51].
4.2.8 Gerald Bull's Superguns William Lowther's book, "Arms and the Man: Dr. Gerald Bull,
Iraq, and the Supergun", [Ref 117], also tells the story of the
superguns Bull was building for Iraq for the purpose of launching
satellites. The following data are excerpted from Lowther's book.
In March of 1988, Bull contracted to build two full sized
guns and one smaller development prototype for a total of $25
million. It was called Project Babylon and was managed by a
British engineer named Christopher Cowley. The small gun was
called Baby Babylon, but it was 46 meters long, had a bore of
35 centimeters (13.78 inches), and weighed about 113 tons [117,
p.187]. Preliminary estimates placed the range at about 750
kilometers (466 miles) [117, p.223]. By May of 1989, Baby
Babylon was being fired regularly in Iraq [117, p.226]. The gun
was mounted horizontally and simply fired into a hillside for
experimental purposes.
The superguns, as specified by Cowley, would be nearly 200
meters long, have a bore of 1 full meter, and would weigh about 2100
tons each. The barrels would have 26 six-meter sections and would
weigh 1665 tons. The tube would be 30 centimeters thick at the
breech, dropping to 6.5 centimeters at the end [117, p.186-7].
Additional recoil cylinders (4 each) would weigh 240 tons and the
breech would weigh 182 tons [117, p.186]. The gun would recoil with
a force of 30,000 tons [117, p.259]. The guns would have no rifling
because the projectiles would be rocket assisted and they didn't
want them to spin. (This of course greatly reduces the cost of the
barrels.) Each shot would require 10 tons of special propellant.
Bull personally briefed both MI6 (the British equivalent of
the CIA) and the Mossad (the Israeli equivalent of the CIA) about
his project. He wanted them to know that this gun was not a military
weapon because otherwise they would stop the project. Since the
barrels were being made in England, the British could have stopped
the project at any time. The key to this argument was that the
guns were so big that they were immobile. Thus they would be
completely vulnerable to air attack. The location of the gun would
become obvious after the first shot. If and when the gun was
fired (in Iraq), the shock would be so great that it would register
on seismographs in California [117, p.188]. Each firing would
produce a 90 meter flame that could be picked up by all of the
orbiting spy satellites. Within minutes everyone would know exactly
where the gun was and it could be bombed out of operation very
easily. The gun's alignment was so sensitive that a bomb landing
within a quarter mile of it would put it out of commission.
Bull intended to launch payloads of two tons [117, p.185].
The initial acceleration of the gun would be in the range of 10,000
to 20,000 gees. Many people, including the Israelis, thought Bull
wouldn't be able to launch anything delicate, but Bull had found
ways to launch delicate guages and timing devices without damage
[117, p.83]. On March 22,1990, the Mossad assassinated Gerald
Bull in Brussels [117, p.281]. On April 11,1990, British customs
seized eight sections of the superguns on the docks in Teeside,
England [117, p.278].
Bull had estimated that his gun could put payloads into orbit
for $600 per kilogram [117, p.219]. Bull was of course aware of
LLNL's hydrogen gas gun, but he had experimented with gas guns
before and considered them inferior to standard propellant guns
[117, p.218].
The projectiles were only in the drafting stage at the time
of Bull's murder. But they were intended to boost the payload
from its ballistic trajectory into orbit with rocket engines in
a manner similar to other launch systems mentioned above.
We have a program which calculates the various parameters
of gun launched projectiles. The following table was prepared
with this program. It shows the approximate cost of rocket
assisted projectiles fired from Bull's gun in terms of both total
cost and cost per kilogram of payload. One can see from the table
that the cost is extremely sensitive to the specific impulse (Isp)
of the propellant.
* Table 4.2.8-1 Cost of gun launched projectiles
Mass Launch Isp mass Payload ( % ) Cost Cost
(kg) angle (s) ratio (kg) 1000s per kg
1600 21 250 6.20 123.7 7.73 $117.4 $ 948
275 5.25 174.9 10.93 $113.6 $ 650
460 2.70 492.8 30.80 $ 90.5 $ 184
1700 20.5 250 6.15 133.9 7.88 $123.9 $ 925
275 5.22 188.5 11.09 $119.9 $ 636
460 2.68 526.6 30.97 $ 95.3 $ 181
1800 20 250 6.11 144.1 8.01 $130.4 $ 905
275 5.18 202.1 11.23 $126.2 $ 625
460 2.67 560.5 31.14 $100.1 $ 179
1900 20 250 6.07 154.4 8.13 $136.9 $ 887
275 5.15 215.7 11.36 $132.5 $ 614
460 2.66 594.4 31.29 $104.9 $ 177
2000 19.5 250 6.03 164.8 8.24 $143.5 $ 871
275 5.12 229.5 11.47 $138.8 $ 605
460 2.66 628.5 31.42 $109.7 $ 175
Assumptions:
1. Muzzle velocity of 3500 meters per second.
2. Launch altitude is 1500 meters.
3. Launch latitude is 5 degrees or less.
4. Single stage booster
5. Tanks and engines weigh 10% of the propellant
6. Fuel cost = $20 per kilogram
7. Tanks and engines cost = $600 per kilogram
8. Additional launch cost of $10,000 per shot
Column
1. Mass of projectile in kilograms
2. Optimal launch angle in degrees
3. Isp - specific impulse of rocket propellant carried
4. Mass ratio of projectile and propellant
5. Weight of payload in kilograms
6. Percentage of payload in projectile
7. Cost of each shot - no amortization of gun cost
8. Cost per kilogram of payload.
.
4.2.9 Sub-orbital gun
Orbital Transport Services is a small company located in Phoenix, Arizona. They are building conventional guns similar to Gerald Bull's guns to do the same thing that HARP did back in the 1960s. Their brochure offers to launch payloads of up to 50 kilograms to altitudes of over 180 kilometers at prices under $100,000 per launch. Bruce and Paul Roth, the founders, believe that they can break even on a mere 8.33 tons of payloads. Payloads will be launched for about $880 per kilogram or $400 per pound. 4.2.10 Summary of exotic launch systems There are two targets we are aiming for: low earth orbit and the moon. It is very likely that one launch system cannot accomplish both tasks cost effectively. The following choices are available for LEO: * Technique Development Available Payload Cost Incr
cost ($ B ) (kg) $/kg $/kg
Hydrogen gas gun 6.0 10 yrs? 340 600 392
Coil gun (EMPL) 4.94 7 yrs? 100 6,000? 1,000?
Railgun(won't work) - - - - -
Two stage gas gun 1.0? 10 yrs? 1000 119 53
Scram gun (work?) 0.5? 6 yrs? 450 ? 330
Supergun 0.1? 3 yrs 300? 600 175
.
It is clear that the supergun should be developed for the
purpose of placing small payloads in low earth orbit because of
its exceptionally low development cost. At $10 million each, the
superguns are so cheap that they could be located at many sites around
the world. If its rocket boosted projectiles were fueled with liquid
oxygen and liquid hydrogen, the cost could drop to less than
$200 per kilogram or $91 per pound or less than 10% of the cheapest
rocket boosted payloads and less than 1% of the cost of the space
shuttle.
The two stage hydrogen gas gun should also be studied to see if
it can really be built within budget and if it will perform as
advertized.
4.3 Current earth launch sites The Soviet Union has launched by far the largest number of satellites and other space missions. The US follows in a distant second place. The ESA and Japan are another order of magnitude behind, but both are expanding their space programs. The following is a list of the locations of the world's major launching centers. * Table 4.3-1 World's major launch centers Site Latitude,Longitude Country Tyuratam 45.6 N, 63.4 E CIS Plesetsk 62.6 N, 40.1 E CIS Kapustin Yar 48.4 N, 45.8 E CIS Kennedy Space Center 28.5 N, 80 W USA Vandenburg AFB 35 N, 121 W USA Wallop Is., Va. 38 N, 76 W USA Kourou, French Guiana 5.2 N, 52 W ESA Shuang Cheng-tzu 41.2 N, 100.1E China Xichang 28 N, 103 E China Taiyuan 38 N, 112 E China Tanega shima, Japan 31 N, 130 E Japan Uchinoura, Japan 32 N, 130 E Japan Sriharikota 13 N, 80 E India Source: [125] Space Activities of the US, Soviet Union, and Other
Countries/Organizations, p.55,71,74,81.
.
4.4 Earth to moon direct
Considering that the cost per kilogram of payload landed on the
moon is about 7 times the cost of the same kilogram in LEO [LB1,
p.66], the minimum cost of payload landed there would be about
$2381 * 7 or $16,667 per kilogram (using the Soviet Proton rocket).
Using the superguns suggested above, the cost might be reduced
to $200 * 7 or $1400 per kilogram. But that would require some very
"smart" facilities in LEO to collect payloads coming up from earth
and to reassemble them into something which could be launched from
LEO to the moon.
Our recommendation is to build an EMPL about four times as long
as the Sandia launcher. With the same acceleration one could then
achieve a launch velocity of about 13 km per second. This would be
sufficient to throw projectiles all the way to the moon.
The following table shows the earth launch velocity necessary
to throw projectiles through the atmosphere and all the way to the
moon. The first column specifies the velocity of the projectile
when it reaches the moon. The other columns indicate the projectile
mass in kilograms. All velocities are in meters per second.
* Table 4.4-1 Earth-to-Moon EMPL launch velocities Lunar Velocity Projectile mass in kilograms
(m/s) 2000 3000 4000 5000 6000
1500 13588 12615 12208 11983 11840
1600 13608 12632 12224 11998 11855
1700 13629 12650 12241 12015 11871
1800 13651 12669 12259 12032 11888
1900 13674 12689 12278 12051 11906
.
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