As before, fly up to a suitable ignition altitude, then light the rocket on the mothership and spacecraft. The mothership’s motor could perhaps throttle to minimize the load on the pylon. Since we have a clean-sheet design, we’ve probably dealt with the issue of rocket exhausts. Alternatively, we could extend the pylon, placing the spacecraft further away from the mothership; this would also help with the pitch-up.
As the pair accelerates, they pitch up, converting horizontal velocity to vertical velocity. Once the desired launch angle is reached, the craft separate. Now the spacecraft is developing little or no lift, but the mothership is still developing lots of lift. As well as this, the pair are still pitching up as separation occurs, so they naturally ‘fly apart’, in much the same way as fighter-bombers ‘toss’ bombs towards a target. So separation is no issue.
The spacecraft continues on it’s own trajectory now, but the mothership continues pitching over onto it’s back, probably with some thrust still coming from the rocket (to avoid slowing down and stalling over the top in the thin air). Once level, it rolls back upright, shuts down the rocket, and returns to base.

This should provide good flexibility of launch angle, launch speed (by using an appropriate pitch rate), and makes separation a non-issue.

But then I’m just a pilot, not an engineer…

~Jon

Googaw’s point, I think, is that space already is open. We’re using it right now. What we’re not doing is living up there. Similarly, we’re not living in Antarctica, the bottom of the ocean, or the Mojave desert (wait, nevermind, some are)… Space is a ridiculously difficult environment to live in; it puts the harshest environments here on the surface to shame, minus perhaps the interiors of active volcanoes and the bottom of the Mariana trench.

We tend to congregate in places conducive to human life, and we generally only use extreme environments in ways that enhance that life. For instance, in mountainous areas, most homes are built in the valleys, and we locate transmitters and radar on the mountain peaks. It’s certainly fun to go to Sunrise Peak overlooking Las Vegas, but quite conspicuously, nobody lives there.

That is not to say that there can’t be an advantage to manned space flight. There are some very productive things I’d like to do in space that are not very conducive to automation with a 10 minute communication lag. Getting into space in creatively cheap ways could very well stimulate demand that we haven’t imagined yet.

Settling low-earth orbit is kind of like settling Sunrise Peak. Unless you’ve got some real competitive advantage in LEO that justifies the cost of sustaining life, besides the fact that you like it there, you can’t sustain it. And the only way it will become cost competitive is with a huge breakthrough in access to orbit, which quite frankly will not happen by optimizing rockets. That doesn’t mean using other space-based resources can’t be economical within a much shorter timeframe. It just means that living there will be like living on an off-shore oil rig, rather than being a nice vacation. Like an outpost.

1-It isn’t “attitude” per se that you care about, but “flight path angle”. Flight path angle is the angle from the horizontal to the *velocity vector*, whereas attitude could just be which way the nose is pointing.
2-Ideally the flight path angle at separation isn’t purely vertical or purely horizontal. I’m not positive about this (Kirk’s the air launch trajectory guru on the blog), but I think what you want is the flight path angle you would’ve gotten had you ground launched and built up to that speed and altitude. Basically somewhere into the gravity turn portion of the flight. My gut feeling says something in the 30-50 degrees range.
3-Ideally your attitude and flight path angle at separation would be really close to or identical to each other.

Not sure if the inversion is necessary or not. It would be interesting to simulate and see which is better. I don’t have really good intuition for how wingy things work…

~Jon

What does survival of the species have to do with the recession? And what part of wasting resources (i.e. using more than you produce) will help real economic activity increase? It’s hard to follow an argument that jumps from make-work for some people in three or four states (Shuttle, Ares) to surviving what would otherwise kill us all.

Yes, the amount of money spent on military is too much. Also, Americans spend a lot of money on video games. Both of these facts are red herrings, distractions from the question of how best to use the fixed resources allotted to NASA, and whether the new allotment achieves better results compared to the old allotment.