Defense Intelligence Reference Document Aneutronic Fusion Propulsion(1)

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• Antimatter drives:
- Antimatter/fission.
- Antimatter, propellant and Laval nozzle.
- Antimatter, electrical generation, ion drive.
- Antimatter, electrical generation, photon drive (Sanger).
• Speculative technologies:
- Heim graviphoton drive.
- Black hole energy source.
To look at the role of fusion propulsion over the next 30 years and beyond, we can
envision four kinds of missions: surface to LEO (low-Earth orbit); LEO to Mars; LEO to
Saturn; and LEO to Alpha Centauri A, B, or C. While technical hurdles will certainly be
at the forefront for each mission, safety factors and fuel concerns will also contribute to
the optimal propulsion technology chosen.
SURFACE TO LOW-EARTH ORBIT (100 MILES)
The energy required to move one kilogram of mass into LEO 100 miles above the
surface of the Earth is about 30 MJ (8.5 kW-hr). The energy required to move this
same mass from LEO to lunar orbit significantly smaller, yet the transit time can be
very long. Chemical rockets, such as the Saturn V, have successfully launched
satellites and the Apollo missions into earth orbit using RP-1 and LOX (liquid oxygen),
along with LH2 (liquid hydrogen) in the second and third stages).
Proximity to the Earth's surface requires propulsion systems that are safe to the
population and to the environment. The Rover Project in the 1950s explored the use of
nuclear fission NERVA (Nuclear Engine for Rocket Vehicle Application) rockets, but
ejection of radioactive debris made these rockets untenable for use on Earth. Fusion
and antimatter systems suffer the same problem. Chemical rockets will continue to
move humans into local space until another technology is available. Given sufficient
technical and financial support, additional systems may be explored over the next 30
years:
• The Space Tether: This involves a carbon nanotube tether that connects a
spaceport on the Earth's surface to a station in geosychronous orbit above the
equator. Carbon nanotubes are extremely strong, yet fibers of sufficient length to
fabricate into a tether are not yet available. This is an active area of research
(http://www.spaceelevator.com) with scientific progress presented at regular
conferences. Cargo and passengers would be moved into LEO using an elevator
attached to the tether.
• SSTO (Single Stage to Orbit): Multistage rockets are now used to attain Earth
orbit since most of the energy expended by the rocket is used to lift the rocket and
its fuel. The space shuttle is based on an earlier design by Eugen Sanger in 1930s
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