Could the First Stage of an Atlas V be made Reusable?

[barrykirk]

What would it take to make the first stage of an<br />Atlas V resusable?<br /><br />Would that make it more or less expensive than the current Atlas V?

 

[shoogerbrugge]

My 2 cents:<br /><br />The RD-170, the grandmother of the engine currently used by the Atlas 5 was meant to be re-usable and they have tested this engine for endurance as well. I suspect that the RD-180 is different but that it should be possible to make it run longer as well. It was planned for the Energia liquid strap on boosters that used the RD-171 to be re-usable, although this has been done so in practice. <br /><br />There are a couple of issues though. The plumbing, don't know if it can deal with multiple runs as well. Recovery, salt water is not good rocket engines, and flying back is rather complicated. The costs of inspecition and overhaul, which is a major bottle neck on the re-usability of the SSME.

 

[vogon13]

IIRC, the burnout altitude and velocity are quite high for the Atlas first stage . . . <br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[scottb50]

The most powerful version of the Atlas V can put a little more than 20,000 pounds into LEO. Every pound of structure used to make it able to flyback would lessen the payload. Since the CCB weighs about 50,000 pounds it would take quite a bit of structure, all of the 20,000 pound payload and probably more.<br /><br />A couple thousand pounds of parachutes and airbags might be a better recovery method. <div class="Discussion_UserSignature"> </div>

 

[barrykirk]

Well, keep in mind that adding 20,000 LBS to the booster stage won't reduce the payload by 20.000 LBS or to zero.<br /><br />It would reduce the payload significantly though.<br /><br />I was thinking parachutes and airbags.<br /><br />If saltwater is a problem for the engines. Could inflatable floatation devices be used to prop the engines out of the drink?<br /><br />Would the reduction in payload capacity and the cost of recovery offset the reduction in cost of building a new booster?

 

[vogon13]

. . . and therefore it is going to splash into the water a considerable distance downrange. Also, heating could be a factor of some significance.<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[scottb50]

Well, keep in mind that adding 20,000 LBS to the booster stage won't reduce the payload by 20.000 LBS or to zero. <br /><br />Sure it would if you still use the same engine and carry the same amount of propellant. You could compromise somewhat by accepting a lower orbit, but then you would need a Tug to pickup the payload before it re-entered. If you have a given amount of thrust, or more correct Delta V available, you can't arbitrarilly raise the launch weight, or Mass Fraction.<br /><br />The Atlas does seem to be somewhat overpowered so you could probably carry some payload if it only took 20,000 pounds of structure to make it fly-back. But, the aerodynamics of wings need to be considered also, the drag would cause even more problems. <br /><br />One idea would be to use a composite LOX tank and put the parachutes at the bottom just above the engines. It would land straight down in the water and flooding the tank would keep the engine out of the water until it is recovered. <div class="Discussion_UserSignature"> </div>

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>But, the aerodynamics of wings need to be considered also, the drag would cause even more problems.<p><hr /></p></p></blockquote><br />My solution there would be to borrow a trick from the Tomahawk: Hide the wings inside the booster until seperation. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[shoogerbrugge]

I think it's not all that smart to save the plumbing and tank of a first stage. The real $$$ money is in the engine. Maybe they can design the first stage in such way that the engine compartiment seperates. This is a lot smaller and easier to control.