"unlike other rocket-less plans for space entry, each relevant technology is advanced enough that tests could take place in 10 years" Meaning a decades-long he

"unlike other rocket-less plans for space entry, each relevant technology is advanced enough that tests could take place in 10 years" Meaning a decades-long hellishly-expensive program. Compare that to the light-gas gun, which is a proven concept and works with current technology. http://en.wikipedia.org/wiki/Project_HARP http://en.wikipedia.org/wiki/Project_HARP A startup working on the concept: http://quicklaunchinc.com/ http://quicklaunchinc.com/ According to the Quicklaunch people, a completed cannon should cost in the vicinity of $400M.