SpaceX set to launch

[D'kian]

This will be a tremendous undertaking even once we have the materials to do it. A *lot* of tonnage must be lifted to geosynchronous earth orbit (GEO), and the elevator tower built outwards from there (both up and down, the center of gravity of this thing must always remain at GEO). I seriously doubt that this will be financially possible without Single Stage to Orbit first.

We'll see. It's too bad we don't already have a space elevator, because using one would be the best and cheapest way to build a space elevator

So what you do, then, is build a rudimentary, least possible working system, just a string from GEo to the ground as it were, and use that to build the real thing that will carry passengers and cargo. It seems outrageous, but it isn't that different from putting up a skyscraper: first you build some structure and a crane taller than the building itself.

Remember that if you climb up this tower to an altitude of 150 miles, you are NOT in low earth orbit, you will have weight, and if you step off the tower you will fall to the ground. You could conceivably jump off the tower and light off a rocket to give you the 7 km per second you need to stay in orbit, but that won't save you much off of boosting from the ground.

Actually it would save you tons of fuel. If you start boosting outside the atmosphere with your weight reduced a bit and some angular momentum, your fuel requirements to LEO will be much lower. You could also climb all the way up to GEO altitude and boost from there (lots more room to fall, higher momentum and lower weight).

Eventually picture six or eight towers rising off the surface, like the spokes of a wheel, with a ring built on them taking up all the room in GEO. The Ring would take up all the GEO functions, and the towers a lot of LEO ones. For the rest you could dangle "satellites" any distance down from the Ring.

What this tower will be useful will be leaving earth entirely; go to the top somewhere way above GEO, and you only need a little extra thrust to break free of the earth. (It will depend on how tall the portion of the tower above GEO is.)

And then there's that. Of course the space elevator ultimately facilitates going off Earth more than it does getting into orbit. that's the point, eventually, to open up the Universe.

[D'kian]

There's a new video out of Flight 4 at http://www.spacex.com

Next launch may be March 2009, with as many as two more launches following that year. No word on when the Falcon 9 will debut. The Falcon 9 and Falcon 9 Heavy are heavy lifters, meant to orbit satellites into geosynchronous orbit or to carry passengers in Spacex's own Dragon capsule. (no word either on Dragon's status).

[Paul Lemke]

I worked on the spacex main stage turbopump. A turbopump is the main heart of a rocket engine. It is the pump that empties the tanks and pumps it into a nozzle block for the combustion chamber. Other main components are the nozzle, the nozzle block, gimble actuators and control, and the tanks.

My role was pretty minor I completed some modifications to the main RP castings and the aft seal carrier for the turbine was my design. Small stuff but I can say that we were one of the major innovative companies to help them get off the ground. Our turbopump successfully worked and did its job on all of the missions. It was other stuff that failed. The first launch was some plumbing a tech forgot to tighten which caused a fire, the second launch was thrust gimbling control, the third was a failure of the second stage tank design and the fourth was sucessful.

I think if Elon does fail it will be because of the FAA, Military or NASA.

[D'kian]

I worked on the spacex main stage turbopump. A turbopump is the main heart of a rocket engine.

Hey, that's neat!

to add tou what you said, a rocket's thrust depends on how much fuel it can burn in a given span of time. A rocket's turbopump moves fuel at astonishing rates.

BTW I've read the Falcon 1 and 1e first stage is supposed to be reusable. Are they in fact reusable? I suppose you'd know for sure.

Our turbopump successfully worked and did its job on all of the missions. It was other stuff that failed. The first launch was some plumbing a tech forgot to tighten which caused a fire, the second launch was thrust gimbling control, the third was a failure of the second stage tank design and the fourth was sucessful.

My understanding of the third launch is that there was too much residual thrust from the first stage, which bumped against the second instead of dropping as it was supposed to. Of course too much thrust can have a variety of cause.

I think if Elon does fail it will be because of the FAA, Military or NASA.

I'm not so sure about the FAA. the other two should be no problem. The military has its own interests ina reliable launcher, after all. NASA will need to outsource a lot of launch work if it intends to survive. Government acquisitions are inneficient, but it's still cheaper for NASA to outsource some work.

SpaceX also developed the Falcon 9 heavy lifter and the Dragon capsule. Dragon's supposed to be used for delivering cargo to the ISS, without any crew, but the potential for manned operations is there. More so is the desire and the ability. Mr. Musk's ultimate goal is a lot mroe ambitious than Earth orbit.