Re:A question for the Rocket Scientists on /. (Score 1)

The other reply to your question is misleading. Yeas you need to get to Mach 25 to achieve LEO, but there is no benefit to accelerating the entire craft to that speed. Why would you send people to LEO? You send satellites to LEO. Satellites don't weigh that much relative to a launch vehicle, so a third stage rocket used to boost the satellite from the "edge of space" to LEO wouldn't have to be that big. The only real issue with the third stage is integration with the first two stages. External mounting would add a lot of drag during the low-altitude flight segment. The thrid stage could be held inside the second stage craft which would protect the satellite and reduce performance penalties to the first and second stages. Ideally, the third stage could be launched out the front of the second stage, but the use of a human pilot prevents that because the cockpit is in the front. I would say that you haven't completely missed something. A lot of people can't shake the Shuttle paradigm of accelerating the entire vehicle to orbit and not just the payload. Thanks for the good question! -Robert