The ships should have various modes of acceleration. here are a few I can think of from largest DeltaV to smallest. * Brussard Ramjet (uses interstellar hydrogen as fusion source, not useable everywhere) * Fusion Thruster * Orion Thruster (nukes with push plate) * Fission Thruster (reactor heating a propellant which is ejected to create thrust) * Chemical Solid Propellant (like space shuttle boosters) * Chemical Liquid Propellant (normal rocket) * Ion Thrusters (https://en.wikipedia.org/wiki/Ion_thruster) * Lorentz force thrusters (only useable in a magnetic field) https://en.wikipedia.org/wiki/Lorentz_force * Resonant Cavity Thruster (https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster) * Solar Sail (https://en.wikipedia.org/wiki/Solar_sail)
The ships should have various modes of acceleration. here are a few I can think of from largest DeltaV to smallest.
Brussard Ramjet (uses interstellar hydrogen as fusion source, not useable everywhere)
Fusion Thruster
Orion Thruster (nukes with push plate)
Fission Thruster (reactor heating a propellant which is ejected to create thrust)
Chemical Solid Propellant (like space shuttle boosters)
Chemical Liquid Propellant (normal rocket)
Ion Thrusters (https://en.wikipedia.org/wiki/Ion_thruster)
Lorentz force thrusters (only useable in a magnetic field) https://en.wikipedia.org/wiki/Lorentz_force
Resonant Cavity Thruster (https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster)
Solar Sail (https://en.wikipedia.org/wiki/Solar_sail)