Timeline

SKY RAMP TECHNOLOGY

      Sky Ramps require no major research since all technologies have been proven.   If fully funded and developed by a competent team, inexpensive space launches could begin within five years.  The first step require site surveys to analyze the terrain at potential locations .  This is inexpensive and should begin immediately.

*construction of a mountainside Sky Ramp        

      Since the entire RLV and sled are completely reusable, the only direct cost per mission is the fuel burned.  An X-33 taking off with 211,000 lbs of fuel, plus almost 100,000 lbs burned by the big sled rockets, times a fuel cost of almost a dollar a pound, results in  around $300,000 per mission.  However, modern liquid fueled engines are advertised to last only 100 missions, so that cost must be figured into each mission.  Since the rockets on the sled will burn for only  ten seconds per mission, they may last 500 missions.  The sled's fuel tanks and "flight" control systems can be reused thousands of times.  

      After initial start-up costs and problems are resolved, an automated sequence will allow launches every hour, while proposed fly-back and fall-back boosters will require days, if not weeks, of preparation and repositioning.  Therefore, one sled can a launch more RLVs each month than dozens of reusable boosters, and will never crash.  Of course there are costs of maintaining the spaceport as well, but there are no costs from replacing expended rockets, expended fuel tanks, or the recovery and lengthy rework of fly-back or fall-back boosters, so this is the simplest and lowest cost method of viable space launch envisioned. This $300,000 direct cost per mission launch cost compares to the average of $700 million per Space Shuttle mission, and the Department of Defense average cost of $90 million per mission using expendable rockets.