From its inception, NASA's Constellation Program (CxP) has been an ungainly mess. Tasked with making lemonade from the remaining gnarled lemon bits of the Space Shuttle, the CxP was President Bush's crack at doing something memorable (Moon, Mars, and Beyond). But like all rocket plumes and a good deal of political rhetoric, this plan was full of hot air from the start.
When Shuttle Columbia disintegrated in the morning of Feb. 1, 2003, US human spaceflight policy was thrown for a loss. With two Shuttle disasters in the first 113 missions, the system was a demonstrable failure in many respects. Over budget, unable to meet mission readiness requirements, and now known to be fragile and lethally unreliable, calls for Shuttle's retirement became too obvious to ignore. Thus, concurrent to preparations for Shuttle's Return to Flight, NASA and the Bush Administration set about developing their Vision for Space Exploration. This program was unveiled in January of 2004, and called for completion of Space Station and retirement of Shuttle by 2010, development of a Crew Exploration Vehicle (CEV) by 2008, a new rocket for ISS resupply by 2012, and a return to human US space exploration by 2014.
By 2006, the Vision established in 2004 became the Constellation Program, and consisted of several interdependent parts. The CEV became the Orion "capsule", to be used for crew transport and support. Ares I was the launch vehicle for Orion, and its design concept had moved further away from the Shuttle-derived hardware of the original Vision. Ares V was the new heavy launch vehicle, intended for launching the new Altair lunar module into low Earth orbit (LEO).
Fast-forward to now, and Constellation has accomplished the completion of its Systems Requirements Review (SRR) phase, and launch of the Ares I-X technology demonstrator. Certain flight-ready hardware is built, but there isn't a major aspect of the program in the beginning of 2010 that is beyond the development stage and into flight test. The Augustine Commission's view has the program schedule moving to the right to the tune of 2017-2019 before Human rating on Ares I is achieved and flown. With Shuttle retirement planned for the end of 2010, that's seven to nine years without a man-rated launch capability in the US inventory.
The sad fact is that, despite the skill and determination of NASA's employees, there has not been sufficient resolve on the part of the US Government (and hence, the US people) to create and then fully fund a rational human spaceflight capability since the Apollo era. We have time and again lurched from the new and shiny to the less-new and less-shiny, and have left a whole host of half-baked technology laying about unused. In my lifetime the X-30 National AeroSpace Plane, the X-33 / VentureStar, the Space Launch Initiative, the X-37 / Orbital Space Plane, and now Constellation were the intended Shuttle replacements, and each has burned through a pile of cash on the way to obsolescence. Now we look like we're going back to SLI-like commercial contracting, probably piggy-backing on COTS, for the LEO stuff. And who knows about the future for heavy lift?
The one good thing about this time around is an admitted focus on developing capabilities and technology first instead of establishing missions and then figuring out how to get there. As NASA's predecessor, NACA worked first to establish and then to further the state of the art in aeronautics through research. NASA has tinkered in human spaceflight development from countless directions over the past four decades. But with some overarching and constantly shifting (Mars! No, Space Station! No, Hypersonics! No, Space Station again! No, the Moon again!) destination throwing the whole plan into disarray with every new administration, there's been no way to focus on significant long-term goals. Buckle down and focus on the big research problems. Develop solutions. Partner with industry. And then plan some kick-ass trips to new and interesting places, and get back to where we've never been before.