Sunday, May 17, 2009
To my mind, this rocket is a great replacement for the shuttle because it will be far cheaper and safer. It is a no brainer to chose large solid motors for a first stage of any rocket system. They don't get the high ISPs, and the per pound cost of propellant is quite high as well when compared to Kerosene or hydrogen, but the real savings come in simplicity. RnD, ground support, and complex engines cover most of the expense of any rocket system. Monolithic motors of any size can be produced at fairly low costs, and reused all the same. One great goal would be submarine hull style solid motors representing a first stage for a 1 million lbs to orbit rocket. The Sea Dragon would probably have worked well with such a first stage. A few of the rockets planned to replace the Saturn V (never produced due to a shift in funding and policy, as well as the Shuttle taking up a ton of resources) had solids as first stage motors.
But to put things simply, other than being a generally better design in every way, this rocket gets something right that the Shuttle got horribly wrong: You don't mix men and payload.