DIRECT Evangelistas Just Won't Give Up

Constantly referring to him as a "fan boy" rather than, for instance, an "advocate" seems inconsistent with your earlier call for us all to just get along.

Keith, being relatively new to NASAWatch, I have to ask- on what grounds do you consider DIRECT unfeasible? Is it really too good to be true? Since my background is primarily in astrobiology and not engineering, I don't know enough to be able to really evaluate it.

The fundamental problem with the DIRECT concept is that it quickly and cheaply solves the problem! Its a potentially cheaper replacement for the Space Shuttle plus it provides heavy lift capability for returning to the Moon.

But government programs that work are a danger to the anti-government philosophy that government is evil and inherently inefficient.

Ironically, the region where this anti-government philosophy is most prevalent are the regions that appear to love NASA the most (at least NASA related jobs) along with their love for other big government programs such as the US military and a government energy corporation called the TVA!

Marcel F. Williams

Giving up doesn't get it done! But, in truth the consistent refusal of the big players that have gotten involved "inDIRECTly"(!)to acknowledge the worth of what is - after all - originally a NASA scheme, has played against the team all along.

As indeed has the fact that the people that did the "donkey work" felt compelled to remain anonymous for VERY obvious reasons. Leaving team members open to remarks of the "...Who are you guys?" ilk. Personal denigration is always the resort of the technically incompetent usually. But in this case, I consider it was fear that the ATK/NASA Top Brass collusion would come out into the open: so closed ranks are the order-of-the-day.

That closed ranks situation being strongly characterized by Shannon's side-mount SD-HLV proposal, which in a sense forstalled what looked like a logical choice leaving politics aside once the Augustine report began to be divined as to - sorree(!) - directions!

Since DIRECT was intended to slot into the place of ARES, the cancellation of Constellation/STS and the "invention" of Commercial HSF, in favor of SPACE X in particular, have left the concept as high and dry as ARES, even though DIRECT is the only viable means to retain an STS-based HLV capability which has the capacity for growth for future in a way side-mount designs do not.
I shall be VERY sad to see it's demise; if only because:had NASA begun with just such a scheme, it would be currently launching large Cargo modules at least to ISS at a cheaper price than the Shuttle, and VSE would be too far down the road to cancel. Along with that other truly promising LV design, the Kistler K-1, R.I.P

Wow ,I have never been one to critique you " Keith" but I guess unbiased journalism was out the window on that Kieth's note eh?..

Damn the Gravity!

I like Keith's anti-DIRECT reporting, actually. It serves as much-needed cold water -- a good balance. Too much of the Internet Space Community has been blindly pro-DIRECT for too long, so much so that NASASpaceflight.com practically had to be put on suicide watch when the FY11 budget was released.

... even though DIRECT is the only viable means to retain an STS-based HLV capability which has the capacity for growth for future in a way side-mount designs do not. ...

(a)"Retain an STS-based HLV capability"? There is no existing STS-based HLV capability, unless one re-defines Shuttle payloads as Heavy Lift.

(b) Please explain why an STS-based HLV capability would be better than a Delta IV-based HLV capability.

A lot depends on exactly what bits of paper and what modifications NASA wants done to make a rocket a human launch vehicle. ULA have said that it would take them about three and a half years to human-rate Delta-IVH (to their standards - I don't know what NASA's are or whether any rocket could meet them).

Could a SD-HLV be quicker and cheaper? That I don't know. Certainly, the DIRECT team would suggest that their machine could be available sooner than an EELV-based 100t lifter. What I do know is this: The highest theoretical IMLEO payload for Delta-IV is in the 70t-80t range, and that only after the deployment of the ACES upper stage system. An SDLV-Inline can lift that same amount in its basic configuration. Add an upper stage and the figure goes over 100t. You also have a bigger PLF.

Ultimately, it depends on what you want to do with your program. You could run a human BEO exploration program using just the EELV-heavies, if you don't mind multiple launch, in-orbit assembly and propellent transfer as an early prerequisite. I will defer to those who know more than me as to whether a DIRECT-like SDLV-Inline would be cheaper, because it can carry more per flight and its bits are technically already crew-rated, than something derived from the EELVs.

Oh, BTW - the shuttle stack lifts about 110t to LEO - Not all as usable payload, granted, that's about 25t + 7 crew, but that figure is definately heavy lift.

> on what grounds do you consider DIRECT unfeasible? Is it really too good to be true?

It doesn't matter anymore. DIRECT is a fix for a problem that no longer exists. (What problem? Ares I was too small, Ares V was too big, both were too expensive, the NASA center districts were too politically powerful, KSC and Florida were too politically important, and no president could cross them all.) Obama's gumption surprised everyone and the DIRECT fix is now a small quirk of history.

You could run a human BEO exploration program using just the EELV-heavies, if you don't mind multiple launch, in-orbit assembly and propellent transfer as an early prerequisite.

That is the architecture I favor, used together with a refuelable space tug that could move between Earth and lunar orbits.

With a space tug, what would need to be assembled in orbit? ( Unless one re-defines orbital rendez-vous, docking, or refueling as in-orbit assembly. )

According to all the "hand waving as fact" engineer wannabees, ANYTHING (including paper airplanes) is cheaper and faster than Constellation.

"With a space tug, what would need to be assembled in orbit?"

That depends exactly on what your mission is going to be and the exact mission profile. In any case, a space tug is slow and can only transport non-radiation-sensitive cargo, not crew (for reasons of radiation exposure during passage through the Van Allen belts).

Initial multi-EELV launched BEO missions would need to have rendezvous between the mission module (lander or whatever) and a fuelled EDS in either LEO or wherever it is you want the mission vehicle assembled. Depending on the masses involved, this may remain the case, even if you use in-orbit refuelling of a dry EDS, post-launch. You can only really get away with launching with a dry EDS if you have only one mission module. Once the spacecraft grows beyond about 45-50t dry mass in-orbit assembly becomes inevitable again. For example: NASA's baseline Phobos mission would seem to require at least five launches.

DIRECT always seems to be referred to as the replacement for this or the fix for that. Why can't DIRECT just be judged and developed on its own merits? Or will it just not work and accomplish goals that we'd all like to see accomplished? Who cares what it is called and what it replaces? Call it FRED for all I care, get it built, and continue the U.S. manned spaceflight program. Before it's too late. Before America is paying $50 million for coach seats on a Soyuz. Perhaps I have a naive view of the subject, but I merely would enjoy seeing more frontiers conquered while I'm still young enough to enjoy and appreciate it. At 48, I look back fondly on the days of Apollo. Sadly, after 130 flights of the shuttle, I couldn't tell you more than a handful of the astronauts names. And if they are riding in that thing in the first place, they are all heroes. I hope John Q. Public still believes in heroes (even if they are going to get kicked off Dancing With the Stars). I do, and would love to see human boots on the Moon again. And ... dare I even dream it? ... on Mars someday.

... Once the spacecraft grows beyond about 45-50t dry mass in-orbit assembly becomes inevitable again. For example: NASA's baseline Phobos mission would seem to require at least five launches.

Mettic tonnes or short tons? Either way, I assign a very low priority to a manned Phobos mission.

It is harmful and counter-productive to daydream and blab about Phobos missions, asteroid missions, or Mars missions before making realistic plans to return to the Moon.

Please tell me what unitary 45-50t dry mass is required for travel to the Moon and back.

Why can't DIRECT just be judged and developed on its own merits?

Please explain why a new very heavy lift missile is required for travel to the Moon and back.

Do your reasons boil down anything to aside from, "We have to do things just like Project Apollo half a century ago, except maybe with a bigger ballistic capsule, so we gotta have a missile as big or bigger than Saturn V"?

Have I thus summarized the DIRECT concept of operations? Please correct me if I am wrong.

Please explain why a new very heavy lift missile is required for travel to the Moon and back ...

I agree a new very heavy lift launch system isn't required to get to the Moon. As a matter of fact, how about we leave the Moon to private industry? Let SpaceX get them there and they can mine Helium-3 (or any other valuable resources they can find) to their hearts content. A new heavy lift launch system is needed, however, to get humans to Mars. Mars represents the next frontier for human spaceflight to conquer. That is what some people interested in the space program long to see. Apollo did the Moon and did it well. But ... it's a big lifeless rock. A planet that may have been very alive at one time is a much more interesting proposition. And I do happen to think DIRECT could be one way to go. Humble opinion, of course.

BTW, I wouldn't presume to correct you, since I doubt you've ever been wrong ...

I agree a new very heavy lift launch system isn't required to get to the Moon. As a matter of fact, how about we leave the Moon to private industry? Let SpaceX get them there and they can mine Helium-3 (or any other valuable resources they can find) to their hearts content. A new heavy lift launch system is needed, however, to get humans to Mars. Mars represents the next frontier for human spaceflight to conquer. ...

Do you expect that Mars will have no valuable natural resources?

If free free free and private enterprise can exploit Moon resources, why isn't the same true for Mars?

So why not leave heavy lift missile development to free and private enterprise?

So why not leave heavy lift missile development to free and private enterprise?

Now you're talking ... leave it all to the private sector. It might just get done. NASA = politics. Politics = inertia. Therefore ...

Do you expect that Mars will have no valuable natural resources?

No doubt Mars will present exploitable resources. But we haven't gone there yet. Probably should have been able to get there by the mid-80's. But NASA (Politicians) shied away from the whole heroic exploration model. The public (bless 'em ...) lost interest in where NASA was going. And who could blame them.

Humble opinion alert ...I just don't see NASA doing anything of historic proportions without big-time political support ($$$), and public interest wouldn't hurt. Real public interest ... not a handful of us typing on our laptops. Ahh, humans to Mars will happen eventually. Just would like to see it in the 21st century, that's all. And it could happen now. It really could. Except for that whole politics/inertia/$$$ problem, it really could.

DIRECT may not be as bad as Ares, but no praise could be fainter. WE'RE NOT GOING TO DO ANYTHING WORTHWHILE BEYOND EARTH ORBIT WITH CHEMICAL PROPELLANTS. WE'RE NOT GOING TO DO ANYTHING WORTHWHILE, EVEN IN EARTH ORBIT, WITH EXPENDABLE ROCKETS. For some reason that quite eludes me, no one but me is interested in building real spaceships. Until that changes, I wish we would just forget the whole thing. Money spent on expendable chemical-propellant rockets is money wasted, just as surely as if it had been spent on "wind turbines".

Not a totally idiotic idea. Certainly, it seems to offer a 'milestone'-based competition similar to how the COTS program is administered:

Milestones:
1. 50t to LEO/20t through TLI launch capability;
2. Robotic lunar free-return flyby in crew-rated capsule;
3. Robotic lunar orbital insertion in crew-rated vehicle;
4. ROI and re-entry from lunar return orbit;
5. Crewed lunar orbit (inc. orbital science and EVA capaibility);
6. Rendezvous and docking in LLO;
7. Robotic lunar lander;
8. Robotic crew-rated lunar lander;
9. Robotic lunar sample return;
10. Crewed lunar landing.

This aside, the answer to the "Why is DIRECT needed?" is:"it can do it sooner", if funded, of course. It probably has a shorter development path than any other lunar-capable launch vehicle. IMHO, at least, the DIRECT concept (D-SDLV in-line) is the only LV that that has sufficiently small required development that money would be available to build lander in the near term. I think that DIRECT is the only serious hope to get lunar landing capability before 2020. The key question is: Does America really want it?