It's been scaled up before from the X-40, and it's not unreasonable to think this could make a rapidly developed crew ferry vehicle with room for four persons.
Not worth doing. The whole stack has less thrust than a Delta IVH.Warning:20MB PDFhttp://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19940028594_1994028594.pdfYou need 6 SSMEs and to stage 2 of them. You get something like 40 tonnes to orbit.4 RS-68s is a better bet but then you are duplicating Delta IVH so why bother?
With all the discussions on saving Orion, promoting commercial crew, and which version of a shuttle derived vehicle has the greatest Messiah complex, the X-37B gets very little mention, and I find that odd. If it flies successfully next month, America has a real windfall. It's not capzble of human flight as is, no, but unlike most of the paper designs and boilerplate hardware, it already exists. It's been scaled up before from the X-40, and it's not unreasonable to think this could make a rapidly developed crew ferry vehicle with room for four persons. I suspect that if it has a successful test flight, and the news channels find interest in it, there are going to be questions asked about why we don't look at this vehicle.