First up is the SpaceX Dragon, which is arguably the front runner in the CCP given it’s successful unmanned cargo mission to the ISS. The Dragon, of course, is designed to launch atop SpaceX’s own Falcon 9.

Next up is SNC’s Dream Chaser lifting body design. SNC isn’t producing a booster, the Dream Chaser is intended to launch atop a ULA Atlas V, though it could possibly be lofted by other man-rated boosters as well.

Next is the Boeing CST-100. While Boeing does have their own booster, the Delta IV (currently produced via the ULA joint venture with Lockheed Martin), there are currently no plans to man-rate it. At this time the CST-100 is planned to launch atop the Atlas V, though it may also use the Falcon 9.

Next is ULA with the Atlas V. Now, the Atlas V is an established launch platform for satellites and unmanned probes, but the CCP work will involve man-rating the launcher so that it can carry vehicles such as the Dream Chaser and CST-100 safely.

And lastly we have the ATK Liberty. Liberty looks an awful lot like the Ares I from NASA’s now-defunct Constellation program, and with good reason. ATK was developing the first stage of the Ares I, which was basically going to be a five segment evolution of the four segment Space Shuttle Solid Rocket Booster. When the Constellation program was cancelled, ATK was well along in the design and testing of their first stage, so they decided to go forward with the work on their own. As NASA was going to develop the second stage of the Ares I they needed to replace it. Rather than design something from scratch they turned to an existing design, the European Ariane 5. The second stage of Liberty is the core first stage of the Ariane 5, with modifications of course.

ATK has also decided to develop their own crew capsule, rather than using Boeing’s CST-100 or the NASA/Lockheed Martin Orion. ATK’s capsule will be based on a composite demonstrator they produced for NASA as part of the Orion project during Constellation. While it was decided not to use a composite structure for Orion, ATK has decided to use their experience building the demonstrator to produce their own capsule. So they’re looking to produce a complete end-to-end system, like SpaceX with the Falcon 9 and Dragon.

There is another participant that doesn’t seem to have a video, yet anyway, and that’s Blue Origin. They’re working on yet another capsule design, this one with a unique biconic shape, which they’re simply calling Space Vehicle. It will initially launch atop the Atlas V, but Blue Origin plans to produce their own Reusable Booster System in the future.

The SLS will initially use the RS-25D, also known as the SSME – or Space Shuttle Main Engine. NASA has a stockpile of these from the shuttle program. Later this will change to a cheaper RS-25E, or expendable, version. Whereas the RS-25D was reused on multiple shuttle flights, engines used on the SLS will be discarded. So there is no need to build the engines to higher standards for reusability. NASA is only using the RS-25D initially since they already have a stockpile of them and with the retirement of the shuttle they have nothing else useful to do with them. The RS-68B the Ares V was to use would’ve been a version of the RS-68/68A already in use on the Delta IV launcher, designed to be expendable.

Most of the increased lift from the evolved version of the SLS will come from new rocket boosters. NASA is expected to compete the design of the new boosters, which could be liquid or solid fueled. But that is still a ‘when and if’ question, since they need to get the initial design off the ground first.

I’m disappointed because I grew up with one program after another promising great leaps. The X-30 National Aerospace Plane – cancelled. The DC-X Delta Clipper – cancelled. (Though Jeff Bezo’s Blue Origin New Shepard program looks to be the spiritual successor.) The X-33 VentureStar – cancelled. The X-34 – cancelled. The X-38 Crew Return Vehicle – cancelled. And, of course, the Constellation Program was cancelled.

At least the Air Force picked up the X-37 after NASA dumped it.

With each cancellation the programs have seemed to get less ambitious. No more space planes, reusable launch vehicles, etc. We’re back to the gumdrop on a stick capsules. Much of the technology in the SLS can trace its development right back to the Apollo program, and the rest is a pretty direct link to the shuttle. There’s not much that can be considered new. That’s safe and (relatively) cheap, but not all that inspiring, at least to me. The first generation SLS reminds me very strongly of the aborted Ares IV concept, which would’ve been kind of a combination of the lower stages of the Ares V and the upper stages of the Ares I.

Frankly I’m a lot more inspired these days by what’s going on in the commercial sector. And I don’t me the traditional giants like Boeing, Lockheed, Ariane, the Russians, etc. But the space start ups that are doing new things. Blue Origin and their New Shepard, as well as their other projects. Sierra Nevada and their Dream Chaser space plane (based on concepts from the cancelled NASA HL-20). But most especially Elon Musk’s SpaceX and their Falcon launchers and Dragon capsule.

SpaceX’s Falcon Heavy is being designed to lift 53 metric tons to LEO. With concepts for the Falcon X Heavy and Falcon XX lifting 125 and 140 metric tons, respectively. While those are still concepts the Falcon 9 has already flown, and the Falcon Heavy is a direct evolution of the Falcon 9 (it was formerly known as the Falcon 9 Heavy) and it is in active development. While it won’t lift even as much as the first generation SLS, I find it more inspirational because it is a small private company developing everything from scratch. There is no legacy technology in the Falcon program, they’ve been inventing a new generation of rocket technology. And so far they’ve been very successful.

While the SLS will surely be a very impressive vehicle if it ever flies, don’t get me wrong, right now that is a very big if given NASA’s track record with programs. I’m not sure we wouldn’t be better off giving the money to companies like SpaceX to accelerate development of vehicles like the Falcon XX. Given their track record on the Falcon 1, Falcon 9, and Dragon to date we might get more for less.

Via CNET Crave.