tag:blogger.com,1999:blog-8062571400334852082.post1972256641690077988..comments2015-03-06T12:15:29.825-08:00Comments on Armchair engineering: SLS Block 1 missions: Returning to the Moon using only the basic SLSMarijn Molemanhttp://www.blogger.com/profile/10374646748718489690noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-8062571400334852082.post-56385514409830175752013-09-21T11:38:52.333-07:002013-09-21T11:38:52.333-07:00Thanks for that. I also concluded that the Block 1... Thanks for that. I also concluded that the Block 1 SLS will have significantly more than a 70 metric ton payload capability. I discuss on my blog getting a lunar mission using all cryogenic in-space stages.<br /> If you assume the payload capability of the SLS is at 90 mT or above then you can do it with hypergolic stages. To save on development costs, I favor adapting existing stages. For instance the Ariane 5 has a hypergolic upper stage that has a very good Isp and mass ratio. Two or three of these should suffice, with a hydrogen-fueled Earth departure stage.<br /> Again to save on development costs I suggest using NASA's SEV at about a 3 mT dry mass as the lunar crew module, since NASA wants to develop it anyway.<br /> Also, since NASA, and the ESA are not completely decided on Orion's service module, I only use the Orion capsule itself's dry mass then estimate some values for the mass of the service module based on the Ariane 5's hypergolic stage.<br /><br /> Bob ClarkRobert Clarkhttps://www.blogger.com/profile/16114043697010364282noreply@blogger.com