The performance of Daedalus was set by a decision, early in the study, that flight to Barnard's Star (less than 6 light years distant) must be accomplished within the lifetimes of the people involved with the project, about 50 years. This meant that Daedalus must reach a velocity of some 24,000 miles/sec (38,600 km/sec).
1 Pellet injection gun
2 Superconducting field coils (4)
3 Electron beam generators
4 Plasma exhaust jet
5 Magnetic field
6 Energy extraction coils
7 Frozen nuclear pellet
8 Nuclear explosion
9 Reaction chamber
After a full examination of possible propulsion techniques, it was concluded that the best candidate was the nuclear pulse rocket. The engine concept is based on studies of controlled fusion in which pellets of deuterium and helium 3 are injected into the centre of a magnetic field.
As they reach the target point they are hit simultaneously by high-power electron beams. The explosion repetition rate is an incredible 250 per second. Principles of the engine which might become practicable in the 21st century are shown in the diagram.