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DIRECT Post-Shuttle Plan Pitched To Obama Team
FleaPlus writes "Popular Mechanics reports that a 'renegade' group including NASA engineers has met with President-Elect Obama's space transition team to present information on the DIRECT architecture for launching NASA missions after the Space Shuttle is retired. According to the group, DIRECT's Jupiter launch system will be safer, less expensive, better-performing, and be ready sooner than the Ares launch system NASA is currently developing, while still providing jobs for much of the existing shuttle workforce. Meanwhile, it's expected that current NASA head and adamant Ares supporter Michael Griffin will be replaced by a new NASA administrator."
The Direct Launch approach, which you can look at in detail here at their website sounds like some people are trying hard to come up with a smart solution, but it isn't clear to an amatuer like me how the current safety issues of the Shuttle would be avoided. I guess maybe because there is no Shuttle for falling foam to hit, for one ?
And yeah, Griffin does come off as a real jerk, esp. when discussing the Shuttle accidents.
They are 'renegade' engineers, and they are 'bucking' their bosses. I'm not sure what part of the factually-correct description you have a problem with.
And knowing the kinds of engineers who work at Marshall Space Flight Center, I wouldn't be surprised if some of them did ride Harleys.
First chance to see if Obama is a retard or not
NASA-engineer: "So Mr. President, will you fund our project?"
Obama: "My Momma always said life is like a box of chocol..."
NASA-engineer: "FFS, not again!"
If you quote this signature there'll be 72 copies of Windows ME waiting for you in Heaven.
That's part of it. Having the capsule mounted on top of the fuel tanks also tends to add extra safety. And because of the relatively low weight of these capsules, you can afford to stick extra safety equipment on them. The DIRECT folks are even talking about possibly putting a tank of water between the fuel tank and the crew module, in order to absorb blast and fragmentation. That has the added benefit of providing a lot more water for use in space than the crews would normally have.
The DIRECT system is estimated to have a Loss-of-Crew rate of 1 in 1100-ish, which is something like 10 times better than the shuttle fleet. It seems like a really good idea, but then IANARS, so don't quote me.
Then comes the Columbia disaster and the subsequent investigation which recommended that shuttle be retired by 2010.
In 2004 Bush announces the Vision for Space Exploration clearly defining our country's goal to resume our manned exploration of the moon and Mars.
NASA conducts an extremely detailed study into literally hundreds of architecture design alternatives known as the Exploration Systems Architecture Study. It is a fantastic report - read it here. The study rejects using EELVs (due primarily to safety concerns)and recommends a shuttle-derived re-using shuttle and Apollo technology across the two launch vehicles (then called CLV and CaLV). The recommended architecture becomes the basis of the Constellation architecture. (Which later replaces Space Shuttle Main Engines (SSMEs) on the CaLV with RS-68 engines and extends teh CLV from 4-seg to 5-seg (which was actually in the original trade space). This configuration was chosen as it was both the safest configuration as well as having one of the lowest O&M costs (particularly compared with alternatives that leveraged SSMEs more heavily.) NASA is finally on a path to returning to a capability beyond LEO as well as dramatically reducing its workforce with the looming retirement of shuttle a somewhat simpler to maintain replacement
Therein lies the problem... as retirement looms and irreversible decisions begin to be made (reconfiguring pads, not-ordering certain long-lead items for shuttle, etc..) that huge workforce of shuttle support finally realize what Constellation means to their job security. Without shuttle and its extremely complex reusable sub-systems, many of these people will be out of a job and their pet projects in jeopardy.
Not surprisingly, there becomes no shortage of personnel at Shuttle-oriented NASA sites who begin advocating against Constellation and for an extension of Shuttle. Adding to the detractors are of course the disgruntled "establishment" consortium of launch providers, ULA, advocating using EELVs. Then there are the Direct guys who are brilliant NASA engineers but this concept was in essence already considered in the ESAS study and deemed less favorable than the CLV approach.
Add to the mix the political baggage that comes with the program's genesis stemming from an unpopular president and the oncoming president's commitment to "change" at all levels of government and you have a perfect storm of opposition - much of it which has absolutely nothing to do with the actual merits of the current design.
People who have not worked on Constellation simply don't understand how much work has gone into it compared with any of the above mentioned alternatives. Of course they look good now. They have been studied by small groups of engineers for months. Compare with the thousands who have been working on Constellation for years. Despite what anyone says about their program being cheaper or faster - any change at this point will result in
"It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
If I'm not mistaken, most people accept that the meaning and use of words change over the centuries, so no, it doesn't matter if they're working for another employer or not.
Both Mercury and Gemini spacecraft have been boosted into space by converted ICBMs (Atlas in the case of Mercury and Titan for Gemini).
While not a NASA engineer, I am a rocket engineer, and I've worked indirectly with NASA. I've also been following Ares and the DIRECT plan in some detail. I believe I'm qualified to say that the DIRECT plan looks better now than Ares did at a similar point in its development. Even including sunk costs on Ares, it seems quite likely to me that DIRECT is cheaper, quicker, more reliable, and more capable. Ares is already overweight and behind schedule; I would rather bet that it will become more so rather than less so before development is done. DIRECT is not immune to the same effects, but it is a much wiser plan in that it has *much* more margin to work with at a comparable stage in development. Its engineers understand that rockets always get heavier as they get closer to completion, never lighter.
Oddly enough, the only way to compare the two projects is to actually look at the details. The fact that one is further along in development than the other does not automatically make it better, any more than it automatically makes it worse. It may take a little bit of effort to make a reasonable apples-to-apples comparison between the two programs, but it is by no means impossible. AFAICT, comparisons of that sort appear to either be products of bureaucratic inertia ("we've already decided on Ares, therefore it must be right") or they conclude that DIRECT appears to be faster, cheaper, safer, and more capable.
If I remember correctly, "nice" originally meant "stupid". Nice try.
Hail Eris, full of mischief...
E pluribus sanguinem
Having the capsule mounted on top of the fuel tanks also tends to add extra safety. And because of the relatively low weight of these capsules, you can afford to stick extra safety equipment on them.
Yes, the capsule designs have a Launch Abort System. It's the thing that looks like a tower at the top of the stack. It is a rocket motor that can yank the capsule away from the rest of the system if something goes terribly wrong.
Of course I can't make a perfect judgment on the matter. However, I think that for someone not directly involved in the projects in question, I'm quite well qualified. And yes, I'm aware that paper projects always look better. The thing is, Ares never looked all that good -- even on paper. The idea that an extended SRB is anything other than a new large solid is a fantasy; it was obvious to everyone with technical knowledge on the matter from the beginning that any nontrivial changes to the SRBs lost most of the advantages of keeping Shuttle hardware involved. Changes to the main fuel tank are less problematic, but still not wonderful. Using only a single (extended, and therefore new) SRB as the first stage of Ares I obviously had problems -- the performance characteristics meant it was being used in a highly suboptimal manner in that application.
To an observer who hasn't been paying attention since the early Ares proposals, I can see how this would look like jumping ship as soon as the paper project met reality, only to start a new paper project. However, that is not an apt description. Ares was based on a set of highly optimistic assumptions -- basically, that the designers knew how heavy the payloads would be, and could design to those targets. Unsurprisingly, the Orion capsule grew in mass and Ares I had to find extra performance to make up for it. In contrast, the Jupiter 120 has 40t of throw capability to LEO for a 20t capsule. The extra 20t is allocated to "extra payload." In the event that Orion gets heavier still (which it probably will do, though a lot of the weight gain has likely already happened), it's far, far easier to reallocate a few tons from "extra payload" to "capsule" than it is to pull those tons out of a hat. That sort of planning is what makes DIRECT better, even when comparing apples to apples. Any aerospace engineer who looked at early Ares proposals should have had warning flags going up in their mind as soon as they saw how small the gap between the target capsule mass and the lift capability of the booster was.
For the record, I think there is a lot less wrong with Ares V than there is with Ares I. The Jupiter is still a better choice, I believe, but the difference is less drastic. There is a middle ground that would cancel Ares I, and use Ares V to launch the capsule -- I think this would be an improvement over the current plan, but that the DIRECT plan would be better still. None of these are how I think the rocket *should* be designed, given ample time and budget -- but replacing the Shuttle is a project that doesn't have ample time. If NASA is to get anything flying soon, it will have to be a suboptimal design that has significant Shuttle heritage. Of such projects that I've seen proposed, DIRECT is the best compromise between doing the job well and something that could actually be built in time.
But similar designs were looked at in the ESAS study and found to be less desirable than at least the initial Ares I and V configuration.
The ESAS is flawed. The solid rocket motors have not been demonstrated to have the reliability claimed for the Ares I. From the history of their use on the Space Shuttle, they have a failure rate of around 1 in 250. The Ares I is claimed to have a total loss of mission rate of 1 in 400. When your first stage is less reliable than you claim the entire vehicle is, then something is wrong. Similarly, it has been shown that the EELV profiles in the ESAS didn't take into account reasonable adjustments to the corresponding launch vehicles for manned missions.
Seriously, the Ares I has been through SRR, SDR and PDR and numerous other reviews.
IMHO, the Ares I shouldn't have passed the PDR due to thrust oscillation issues. It was given a waiver on that.
Three years ago Ares look fantastic on paper as well - then the reality of engineering development crept in and there are indeed challenges to overcome. Any other program (Direct, EELV, etc) will have the same unkown snags in their future. Oh, and the first Ares test launch is this summer.
No, the Ares I didn't look that fantastic. There are two glaring problem, ignoring the rest. The Ares I competes directly with commercial rockets, the Delta IV and Atlas V rockets. Private industry always gets screwed when that happens no matter how shoddy the NASA solution is. NASA doesn't develope the heavy lift vehicle till 2016 or later. That huge 11+ year delay is why the DIRECT design is so well developed now. Frontloading cost and backloading capability is a common source of failure in government projects. Even the Shuttle didn't do this.
No, the first Ares test launch is on or after 2013, when the Ares I-Y launches. The Ares I-X doesn't use a 5 segment first stage, doesn't have a real second stage, and doesn't have the avionics that will be used on the Ares I. The critical fixes for the thrust oscillation issues might not even be fully tested on the Ares I-Y and that's four years away! There are a few things that the Ares I-X can test (it'll have the right airframe and mass distribution, the right launch pad, and should be able to see thrust oscillation) so it isn't a complete waste.
Ares I is an abortion, and Ares V is being made without specific applications in mind. With the specs changing so often, I doubt either will ever fly.
Why, oh why, did NASA drop funding for SLI which was supposed to develop new generation staged combustion engines? Developing new engines is the first step in developing any new space transportation system. If we had RS-84, or something like it, it would change the game. We need to develop technologies for reliable and cheap access to orbit dammit, not gigantic White Elephants made of old tech, that is fitter for launching nuclear warheads than people.
Then there is the fact that they dropped landing, like the Russians have done for yonks, in favour of dropping into the ocean. What a retrograde step! If they couldn't make the stupid air bags light enough, they just needed to add retrorockets like the Russians. That capsule is too damn big anyway. They should shrink it into something that can fit an EELV.