That's one giant leap backward for Mankind...
In 1993, at Huntsville, Alabama, USA, at the Space Programs and Technologies Conference and Exhibit, a few Boeing engineers presented a fairly old concept; a two stage reusable spacecraft. Page one of the paper can be seen at http://pdf.aiaa.org/preview/1993/PV1993_4161.pdf
Safety issues with the Shuttle orbiter have *always* involved damage caused by the archaic solid rocket boosters, or foam shedding from the external fuel tank. The concept of discarding half your space vehicle at every launch has led directly to the loss of Challenger and Columbia, along with 14 astronauts.
And now NASA wants to discard the *entire* launch vehicle again.
It's time for a total replacement of the NASA administration. These people are without vision.