The IIS Express

[marcel_leonard]

It looks like OSP has won the race to that bid... <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[halman]

Even if you cancel 50 percent of the orbital velocity, you still end up entering atmosphere at a pretty high velocity, because the angle of descent has become much steeper. At least, that is the way that I understand orbital mechanics. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[marcel_leonard]

What about a ScramJet/VASIMR mix of plasma propulsion? <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[nacnud]

Well a scram jet can't get you from zero to hpersonic speeds alone and even when up to speed can't reach orbit. VASIMR is a purely space based technology.<br /><br />A scramjet/VASIMR powered vehicle wouldn't be able to get off the launch pad and if it could it wouldn't be able to reach orbit anyway, seems a bit useless to me. <img src="/images/icons/smile.gif" />

 

[marcel_leonard]

Not if you look at replacing the current use of rocket propulsion which consists of some type of chemical burn; and replace it with plasma, which has the potential to provide us with even greater thrust... <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[nacnud]

So what are you proposing to use in order to make this plasma?

 

[marcel_leonard]

That's the million dollar question, and I'm still working on a million dollar answer.... <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[marcel_leonard]

How about some retro-fitted Delta 4 HLRs w/ OSP functionality? <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[halman]

marcel_leonard,<br /><br />In terms of re-entry, plasma propulsion has some serious drawbacks, in that the direction of travel is also the direction of thrust. Flying into the exhuast of a plasma rocket is not advisable, I believe.<br /><br />Basically, unless you have the ability to cancel ALL of your orbital velocity, and then to balance the vehicle in on its tail, re-entry is going to involve moving through the atmosphere at high velocities, because you have the energy of orbital speed, plus the energy of the altitude to deal with. The whole concept of aerobraking on re-entry is to minimize the propellant requirements.<br /><br />By using a space anchor, the dangers associated with moving through the atmosphere at hypersonic speed is minimized. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[fatjoe]

I've been giving the whole plasma propulsion idea some thought, and I thought the first thing do would be to find natural occurrences of plasma in nature. Unfortuantly the only natural occurrences happen on the Sun... <br /><br />Unless someone out there knows how to reproduce this process in the laboratory?