Electromagnetic Earth-to-orbit launch concepts - One strategy in achieving reductions in launch costs beyond the 'next generation'

Abstract

Significant reductionsin the costs of space launch are a prerequisite for the expansion of commercial activities into space. Since the earliest days of space exploration and exploitation, the costs of Earth-to-orbit (ETO) transportation have restricted the use of space to government missions - large!y science, prestige, military, and weather observations - and selected high-leverage commercial activities - predominantly in telecommunications. Current launch costs using US. systems range from approximately $7,500 per pound to $15,000 per pound to low Earth orbit (LEOJ, depending on the size of the payload being launched and the vehicle being used. Recent changes in nationa! space launch policy have established leadership in enhancing Force (USAF), and for NASA in developing the technology for a new reusable launch vehicle (RLV). These developments, which wi!! require considerable private sector investment, are likely to achieve reductions of 3:l to 5:i in US. launch costs - Le., down ~ ~ ~ to $1,500 to $2,500 per pound for launch to LEO. These improvements will dramatically governmentspace activities while overall government space budgets remainw?ssentially flat. However, the additional reduction of another 3:l to 5:l - i.e., down to less than $500 per pound to LEO - that is needed to stimulate a privately-financed commercial space ~~~~ Electromagnetic (EM) launch - in combination with other systems - represents one possible strategy for achieving the factor of 340-5 additional improvement that is needed. Since the early decades of the 20th century, accounts of EM gun launch to space have existed in fiction. The appeal of directly using electrical energy to achieve extremely low- cost ET0 transportation is intuitive. Such concepts flourished in the 1960s andW370s drivers' for applications in space. Euring the 1980s, EM guns were intensively studied as large, robust in space operational infrastructure to justify the !aunch of inert payloads such as water. Neither event will occur in the near future. Neverthetess, recent developments suggest it may be time to reexamine EM approaches, with a new focirs-on low-speed catapults (poteiidially in combination with higher muzzle velocity EM guns)and~ hybrid EM-rocket systems as a s!rategy for achieving very low cost space launch. This paper provides a cursory view of the topic of electromagnetic ET0 launch concepts, and suggests directions for the development of these technologies so that they will be available for application in the years immediately beyond the next generation of space launch systems. ~~~~~~ ~ ~~ ~~~ ~ expendable launch vehicle (ELVs) for the Department of Defense (DOD) in the US. Air ~~ ~~ ~ enhance U.S. competitiveness in the space launch market and wirl allow real growth in c ~~ expansion is not likely to be achieved by these next generation systems. ~~~ ~~~~~ ~ with the invention of superconducting magnetic levitation and the development of 'mass ~~ ~ ~~ ~~~~~ a potential ~muiZ,e element c velocity of EM a ~systems~require~ future Strategic Defense Initiative c~a~n~~es (SDIldeployment. i~nspa~cec~raft~d~esig~n~and/o~r However, a .- ~~~~~