I didn’t know about this project until today and I have to say that it does look a lot smarter and cost saving than Ares.

First, Direct 3.0 Jupiter is not intended to perform the same missions as the Shuttle. The Shuttle as really only suited for simple LEO missions, such as ISS missions. Direct 3.0 Jupiter, by contrast, is primarily targeted for heavy lift to LEO and missions outside Earth orbit. In other words, Direct 3.0 isn’t replacing the Shuttle, EELV is. That’s true even for Constellation, because Ares I is crew-only and is likely to be canceled in favor of EELV (or rockets of a similar class) anyways.

Second, regardless of how it “feels”, the reality of the shuttle never lived up to the dream. It was never fully reusable, and you could never turn a shuttle around with any real speed. Two Delta IV Heavy rockets can lift nearly the same amount of cargo and the same number of crew (in an Orion capsule) as one Shuttle, and you don’t have the enormous transport costs involved in getting the Shuttle back to KSC.

I love the Shuttle, and I think someday we’ll return to it like we’re currently trying to return to the moon now. However, until we can build a true spaceplane that can takeoff unaided into space, land back on earth and take off again in a matter of days or even hours, shuttles just aren’t practical. It may not be sexy, but it’s the truth.

If you would like a future interview, drop me a line.

ARES, on the other hand, develops two completely different launchers that have almost nothing in common with each other, or with Shuttle. There will be two separate development efforts, two production lines, two sets of tooling and expertise, two different high-bay configurations in the VAB, two different mobile launch pads, two different launch towers, etc etc. Needless to say, all that duplication of effort costs tons of money and time.

The Jupiter cores are identical and can be interchanged as needed. The J-130 flies with three SSMEs, and the J-246 launches with four. Jupiter has much more in common with Shuttle, and does not require any engine development at all. The boosters are identical to the Shuttle, the core tank is closely derived from the Shuttle ET, the main engines are SSMEs, and LEO missions do not require an upper stage at all. In fact, the J-130 can launch 40 additional metric tons to LEO, with a fully functional six-crew Orion.

The J-246 adds an upper stage with six RL10B2 engines borrowed from Centaur, which gives it the ability to lift 110 metric tons to LEO. The DIRECT plan calls for two J-246 launches for Lunar missions, with a combined capacity of 220 metric tons. ARES, on the other hand, is planned to use an Ares-I and an Ares-V for Lunar missions, with a combined capacity of 218 metric tons to LEO, so they are very comparable.

And that’s not even taking into consideration all of the problems that the ARES development teams have been having! Three years in and Ares-I hasn’t even completed its PDR yet. We’re still waiting on a “delta” PDR to take into account the changes made to handle the Thrust Oscillation problem. And Ares-V is still very much in the “paper rocket” stage. NASA’s specifications for Ares-V simply list what it will be required to lift in order to fulfill its mission. They don’t really have a good handle on how to actually make it work.

This post is already too long, please go to http://www.directlauncher.com for more details.

Thanks,
Mark S.