Feasibility of Baker's Ares today?

[najab]

The 5-segment booster would, I believe, be man-rated already since it incorporates all the redundant features and inherits the wall/joint/nozzle design from the 4-segment. I can't remember off-hand, but I don't think the RS-68 has as sophisticated health-monitoring as the SSME. That, if I am remembering correctly, would indicate that it isn't man-rated.<p>But, considering that we are talking about a HLLV, man-rating is not important: if you're putting your crew on a HLLV, there's something <b>seriously</b> wrong with your mission architecture.</p>

 

[mrmorris]

<font color="yellow">"But, considering that we are talking about a HLLV, man-rating is not important: "</font><br /><br />You stole my thunder, Naja -- I was going to ask the same thing. Why in the world do you need (or want) to send your people up with the cargo? To man-rate your HLLV *right* -- there's going to have to be an LES option, along with health monitoring, etc. -- which cuts significantly into your cargo capacity. The HLLV should be designed to maximize the tonnage you can get into orbit. You then have a second, smaller booster designed to maximize the chances of getting your crew safely into orbit. Combining the two is not an optimal solution. Getting people and cargo into orbit is such an expensive operation that using a solution that is known from the beginning to be non-optimal is simply "a bad idea".

 

[smradoch]

>> Why in the world do you need (or want) to send your people up with the cargo? <<<br /><br />To get 3 men directly to Moon without any equipment you would need at least 60t to LEO (with LM refueling at Moon). That's the reason to human rate HLV. Other reason is more launches for new vehicle. One launch delivers cargo and habitat directly to Moon, another launch delivers crew in CEV to LLO and in simple LM to Moon. After refueling of LM with hypergolics (cca 1-2t) delivered in cargo flight you can go back to the CEV at LLO. <br />Otherwise you would need a randezvous with EDS or TEI stages at LEO or at LLO or refueling lot of cryogenics at the Moon base. That's much more complicated mission. <br /><br />One important note - I'm talking about 80t SDV vehicle with cargo or CEV at the nose. (2xSRB,2xRS-68 under moifiedET and upper stage serving as EDS - 1x RL-60?)

 

[smradoch]

I suppose that human-rate SDV would be easier than human-rate EELV. On the other side Crew escape system can be the same, CEV can be the same and safety improvements for RS-68 can be the same. The problem is that EELV would be suitable for LEO, GEO or light cargo operation only if this would happen.