Many studies have examined the engineering requirements for an interstellar fusion propelled mission for the 21st Century, including a comprehensive NASA study in the early 1990s. These same studies considered variations in specific power from 1-100 kW/kg for mission profiles lasting 100-100s of years and examined 1-4-staged engine designs for both flyby and rendezvous type missions with specific impulses varying up to 1 million seconds and with varying jet power ratings.
In the 1970s members of The British Interplanetary Society (BIS) designed an interstellar flyby spacecraft called Daedalus. The design aim was to produce a design with a specific power of 100 MW/kg which corresponded to the optimum mass ratio, but is a million times higher than the NASA studies had examined. However, due to a longer mission profile than originally planned the design for Daedalus ended up having a specific power of around 40 MW/kg.
This paper considers the range of specific powers for an interstellar mission in the application of inertial confinement fusion propulsion type systems using propellant combinations such as D/D and D/He3. These methods are being examined for the recent Project Icarus which aims to evolve the Daedalus probe to an improved design.
Due to the ability of antiprotons to an-nihilate with ordinary matter with 100% efficiency, antiprotons serve as an exceptionally high-energy density storage mechanism. Upon annihilation, sufficient energy can be generated to trigger fusion reactions. In this paper we study a variety of ways that antiprotons can be utilized as drives for fusion ignition. In addition, we explore a number of specific anti-proton driven fusion propulsion concepts. This includes volumetric ignition, hotspot ignition and fast ignition. We also explore various antiproton driven magnetically insulated inertial confinement fusion schemes, including antimatter driven P-B11, anti-proton driven inertial confinement fusion and gas core antimatter rockets. The technology maturity of such concepts is examined, and considered in the context of Project Icarus, a theoretical engineering design study for an unmanned interstellar probe.