A Conversation for The Bussard Ramjet - an Interstellar Drive?

American spaceflight technology

Post 41

Researcher 208766

Orion uses massive Pneumonic shock absorbers behind
its intertial plate to absorb, and store all the momentum
that is given to it by the expanding debris from a
nuclear weapon explosion behind the inertial plate.
Then this momentum is slowly released at an
acceleration rate for Orion of 1 G by the expansion.
Orion would operate only in space and thus the
radioactivity released by it, is not a threat to
the Earth. The crew would be safe from all the
radiation because Orion would be made of heavy thick
steel that will shield the crew from all the nuclear
radiation released by the nuclear detonations that drive

Interstellar ramjet design

Post 42

Researcher 208766

Here is a way to make a nuclear electric ion drive ramjet to
propell a robot star probe to Alpha Centauri.
1.The vehicle will be launched into leo as a single
20,000 kilogram mass module.
2.The mass ratio is 2/1
3. The vehicle is powered by a nuclear fission reactor
that uses thermionic thermocouples to convert heat
directly into electricity. Its output before power conditioning occurrs is 1000 amps of dc current at a maximium ev of 11,000
4.The nuclear reactor is a breeder type fission reactor
, that breeds new fission fuel in its core at the same rate
that it fissions its initial atomic fuel load.
5.The vehicle carries a propellant load of 10,000 kilograms of
liquid hydrogen that is stored inside of a kevlar insulated
2000 kilogram mass titanium metal tank.
6.The nuclear reactor has a mass of 5000 kilograms .
7.The nuclear reactor is designed to generate up to 2000
watts of electric power for each kilogram of its mass.
8. The vehicle has 1 ion ramjet engine, and two ion rocket
engines.All 3 engines have a specific impulse of 14,000 seconds
9.The exchaust velocity of all three of the ion engines is
designed to be 140 km/sec, and the engines accelerate a
maximium mass of 1 gram of ionized hydrogen gas per second.
10. When the vehicle operates in rocket mode the two ion engines accelerate .5 Grams of ion mass per second, per engine.
11. The Ion ramjet engine accelerates 1 gram of ionized
hydrogen gas per second.
12.1 gram of Ions expelled at an exchaust velocity of 140
kilometers per second will generate a thrust of 924 pounds.
13. This will accelerate the craft at 924/44,000 Gs.
14. This is .021 Gs. On earth the pull of the earths gravity
would be 44,000 pounds on this ship. This 44,000 pounds
of gravitys pull would make it fall toward the earth at
9.8 M/sec.
15.The thrust of the ion drive is the fraction .021 of
this force. That is where I get the .021 Gs accleration
16.In each of the ion rocket engines there is an electric
discharge between the anode, and the cathode.This will
strip away the electron from each of 3.01 * 23 power
hydrogen atoms, and turn them into + ions.
17. Then here are two negatively charged 10 meter *
by 10 meter aluminium screens which are .34
meters from each other.The first screen has a voltage
of - 1000 Ev on it and the second screen has a voltage of
- 11,000 Ev on it.
18. The ion ramjet engine has three aluminium screens in
a line . Screen 1 has - 100 ev, and is placed directly in the
mouth of the Electromagnetic bussard ion collector.
Then behind screen one there are two more screens.
Screen 2 has a charge of -1100 ev on it, and screen 3 has
a charge of -11000 ev on it.

19. The bussard collector has two uv lasers attached to it.
These uv laser beams fire periodicly to ionize all the gas
that floats in space within its ion collection radius.
20. The bussard elecroagnmetic ion collector consists of a hollow stainless steel cylinder that is open on both ends.
This steel cylinder has 100 high gauge stainless steel
solenoid coils wrapped around it symmetricly.They are
charged with 1000 amps of dc current.They are cooled by
the direct thermal radiation of their waste heat into the
cyrogenic cold of space whose temperature is like -400 K
21.The elecromagnetic bussard collector generates a 100,000
gauss or ten tesla field.The Strength of the Icm natural
magnetic field is 10 to the - 6 power gauss.
22. The maximum magnetic ion collection radius is the
distance in meters at which the ramscoop is greater then
then the Icm field. The magnetic collection field declines
by the inverse sqaure of the change in distance measured in
meters from its source. The product of 100,000 * 1,000,000
is 100,000,000,000,000. The sqaure root of this number by
the inverse square meters is the magnetic ion collection
radius in meters.This number is 10,000,000 meters whch is
1000 kilometers which is 600 miles.
23. The hydrogen ion density of the Icm is held here to be
1,000,000 ions (protons) per cubic meter of space.
24.The stength of the Icm electric field is 1 * 10 to the
the - 27th power ev. The -100 ev electric field will draw ions
into the bussard collector from a distance in meters = to
the sqaure root of 10 to the -29th power .The electric field
like the magnetic field declines by the inverse sqaure law.
25. The electrostatic ion collection radius is 3 * 10 to the
14th power meters which is 10 to the 11 power kilometers which
is 100,000,000,000 kilometers or 60,000,000,000 miles
25. This proves beyond a doubt that this ramjet will get at
least 1 gram of ions per second from space. It might get
much more then this in fact which might make it necessary
to use much weaker electrostatic, and elecromagnetic ion
collectors fields if the ion drive drive system is used.
26.Larger amounts of ion collecton mass can best be accomadated
, however by using a magnetic plasma drive instead of an
ion drive.
27.To find out exactly how many ions will get scooped you
may Calculate the exact number of cubic meters of space
in the collection area, and the multiply them by 1,000,000
ions per cubic meter. Then calculate the grams of protons
collected by deviding this number by 6.02 * 10 the 23 ions
which is derived from the use of avagadros mole atom
calculation formula. The devide by 1000 to find out how
many kilgrams of protons will be collected from space.
28. I invite everyone to use your ramjet math skills
to perform these calculations et el in order to improve
the concrete calculation of ramjet design performance.
29.At an acceleration of .021 Gs the ramjet will achieve
21% of light velocity in ten years of acceleration.
30 The ramjet may achieve up to 80% of light velocity
within 50 years of acceleration, and within 100 Years of
acceleration it might do something like 99.99 % of light
31. The ion rockets are used to send the craft out of
the solar system at about 100 kilometes per second.
32. Then the Ramjet is switched on to accelerate the
craft to higher velocities.
33. The magnetic scoop makesthe ions in space spiral around
its magnetic field lines. The motion of the vehicle
through space scoops the ions up, and the -100 ev electric
field on the grid at the ramjets mouth serves as an
electrostatic pump to pull all the ions efficiently inside
of the ion ramjet engine.
34.For those who want to make the greatly overrated drag
arguement against ramjets the electrostatic pump ensures
that any drag generated by the ion scooping process will
always be very much less then the amount of thrust that
the ion ramjet engine will generate.This means there will
always be a net vehicle acceleration that gradually pushes the
ram ship velocity closer , and closer to light speed over time.
35. The power source is a breeder reactor that may start out
with say 4% enriched Pu239 or U235 or U233 , and will breed
36. fission fuel generations before the reactor is totally
burned out. If each fuel geeration last for 10 years then
the reactor can potentially maintain maximium power output
for about 260 years of continous ion ramjet engine thrusting.
37.Even when all fissiles are burned up the reactor core will
remain intensely radioactive for still centuries more after
that, and it will generate enormus amounts of radioactive
decay heat that the thermocouples will continue to turn
into electric power indefinitly .So how close to C
(light speed)will we get?
38. For how for many centuries, and mellinea will there still be enough electric power to run the ramjet engine at a useful
level the instruments, and communicatons et el?
239. I invite you all to flex your mathematical
muscles to find out.

40. Questions comments, math calculations et el anyone?

Timothy J Mayes 2-2-2003 A D
From State of Texas , United States Of America

could up 99.99% of light speed + in delta v.

American spaceflight technology

Post 43

Researcher 226295


Proton fusion isn't impossible, but it is really, really slow. Within the Sun's core (an extreme place 150 times denser than water and a toasty 15,000,000 K) protons have a half-life of ~ 5 billion years. Fortunately for life on Earth, but unfortunately for practical interstellar rockets. To get higher performance the reaction temp has to be incredibly hot (a billion K or more), and as a result it starts losing energy from the fusion plasma as x-rays and even gamma-rays. The plasma cools way faster than it is heated by proton-proton fusion.

In other words it's too hard for our limited imaginations and physical knowledge. But perhaps there are other ways. One VERY speculative prospect is 'catalysis' by mini-black holes or lumps of degenerate quark-matter. Hard to do, yes, but not utterly impossible.

American spaceflight technology

Post 44



Thanks for that, 226295 (or can I call you 226? smiley - winkeye)

I hope you stick around and use the site some more - it's given me a lot of entertainment for a good couple of years now. Hope to see you around - we can always use someone who really knows their stuff.


American spaceflight technology

Post 45

Researcher 234037

The fact that protium fusion procedes very slowly is why it
is not practical to base a fusion propulsion system on protium
fusion from the engineering point of view.
It is however practical to base a nuclear fusion drive on duterium/dueterium fusion or duterium/tritium fusion.

American spaceflight technology

Post 46


Yes political, still political and decided at levels ordinary citizens are not privy even presidents of the united states are not privy to. See the military industrial complex speech where president Eisenhower explains the facts of life.

Key: Complain about this post

American spaceflight technology

Write an Entry

"The Hitchhiker's Guide to the Galaxy is a wholly remarkable book. It has been compiled and recompiled many times and under many different editorships. It contains contributions from countless numbers of travellers and researchers."

Write an entry
Read more