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The question is, which launch vehicle will Kliper ride on? Zenit is mentioned most frequently, but it's not "man rated" and it's not favored by the Russians because it's built in the Ukraine. Onega is an option, but where is the money to fund the new upper stage? Angara is a third choice, but that rocket is stranded in development and funding woes that may not be resolved until after 2008.
I'm not accusing Zubrin of heresy here; I just think that he's giving up on the superior "Moon Direct" architecture for a mission that can be done cheaper and faster (but not better.)
I think Zubrin's primary motivation (made clear by his presentation at the Mars Society convention) is to quickly develop a moon program to the point where it has too much momentum to be killed by the incoming administration in 2009.
Zubrin is underestimating the political concensus that the Vision for Space Exploration currently enjoys. The challenge is to build an image of an "American Space Plan" instead of a "Bush Space Plan." For now, the forceful support of a few key lawmakers like Tom DeLay and Kay Bailey Hutchinson has gotten the VSE the funding it needs. Perhaps they will stick around long enough to sustain the plan after 2008. Maybe the public support can be built to the point that it will be political suicide to cancel the VSE.
When you give people the choice of VSE or the Shuttle-ISS, ten out of ten will decide in favor of VSE. When you start giving them large numbers about how much VSE might cost, they'll oppose VSE to the bitter end.
I'd be skeptical of anything I read on SpaceDaily, seeing as how most of it is sensationalized reporting from Agence France-Presse. I remember a recent story about "America's space program in turmoil." Their two sources were Dana Rohrabacher (who sounded wishy-washy about the shuttle in the article, but never called for outright cancellation,) and Barney Frank (who has consistently opposed the space program in favor of increased social spending.)
The media is almost totally united behind the "cancel the shuttle" mantra. I'd like to say "keep it flying" just to spite the press. Pragmatically, we'll have to make a decision based on whether NASA can fix this foam problem in a reasonable amount of time. If they can't fix it by an arbitrary date (say, March 31, 2006,) we should cut our losses with the shuttle.
It looks like Zubrin has renounced the "Moon Direct" plan he advocated in "Case for Mars." He used to support two HLV launches (one for the fully-fueled return vehicle, one for the habitat lander,) with a rendezvous on the lunar surface. A similar idea was used by NASA's "First Lunar Outpost" study, which envisioned the Saturn-derived "Comet" booster.
A two-launch scenario like the one Zubrin originally wanted makes much more sense than what he's proposing now. That way you can land decent-sized payloads on the moon and let the humans stay for extended periods of time so they can perform real science. Weight growth becomes a fear of the past.
The paradox of the Shuttle-SDV program is that improving its efficiency (by using automated processes instead of human labor) will decrease the program's political standing. I must confess to having a personal stake in the shuttle's standing army, as I have friends who work on the program. At the same time, my ultimate loyalty is to the American taxpayer, and I believe that providing them with the best exploration value is our greatest concern.
If the SSME is phased out in favor of RS-68, I suspect that most people who worked on the shuttle's engines would be transferred to work on the SDV engines. Still, this creates a gap of several years between the shuttle's 2010 retirement and the first flight of SDV (which may not occur until 2018, depending on the funding profile. The Stick will hopefully be ready by 2011.)
People who think that SDV will reduce the size of the shuttle army are missing a lot of details. The shuttle's life support people will get reassigned to CEV life support; the shuttle propulsion people will transfer to CEV propulsion and SDV propulsion. Very few positions will be eliminated, and new ones will be created; it's just that the number of people needed to fill those positions might decrease.
The site specifically mentions the development of an "expendable SSME." NASA is going to have to justify why we should redevelop the SSME to be thrown away instead of going with the expendible RS-68. True, the SSME has a higher ISP (~450s vs. 410s,) but it also has lower thrust and a higher parts count.
Nasawatch.com is now predicting a March 2006 flight for Atlantis.
According to NASA sources, serious consideration is now being given to a March 2006 launch date for STS-121. The results of the Tiger Team working the foam issue will help guide that decision in the coming weeks. Stay tuned.
No, no amount of intermediate technology demonstration makes up for an inherintly terrible design. Period. The design was unfixable... of the USAF glide and lift requirements, the (publicly stated) NASA desire for cheap/easy/safe reuseability, and the GAO/WH desire to develop it for a fraction of the money it needed... Pick one, and only one.
I totally agree that the shuttle config could never have been successful. In an alternate timeline, I can forsee an x-plane (like the X-20) giving the engineers evidence that all spaceplanes will be more challenging than originally thought. If a simple design like the X-20 gave the engineers a hard time, there would be no way that they'd agree to the monstrosity that became the shuttle. If they knew what was good for them, they'd tell their bosses that they cannot design a reliable vehicle that met the USAF mission requirements.
First, I have to eat some humble pie... NASA's released the STS-121 patch.
Part of the space shuttle's problem is that it moved directly from technology development to operational use, with no technology demonstration phase in between. Perhaps if somebody built a smaller shuttle prototype (like the X-20 Dynasoar,) the engineers would have figured out what kinds of flight rates were realistic, how to protect the vehicle on re-entry, how manpower-intensive it would be to prepare the vehicle for flight, and how expensive it would be.
Going back to what GCNRevenger said about Challenger, I think that parallel staging proved to be just as deadly as mounting the orbiter in a way that made escape impossible. If the shuttle was serially-staged (with a single huge SRB below the tank, or some similar configuration,) an o-ring burnthrough would have been survivable. Instead, the gas escaping the o-ring burned through the attach strut, the SRB impacted the nearby ET, and the vehicle exploded.
It appears that NASA has finally come to reject parallel staging for manned vehicles, passing over the heavy EELV's in favor of the stick. Jeffrey Bell pointed out two years ago that the failure of a single engine in the Delta IV Heavy would spell the end of an OSP mission (unless some cross-feed system was introduced.)
My resistance to "The Stick" is shrinking because it can't suffer the same parallel staging failure as Challenger did. If an o-ring failed, the stick's SRB might burn out prematurely (forcing a mission abort,) but not a catastrophic failure.
I'm pretty confident that Atlantis will launch in November. Fixing the PAL ramp isn't hard; NASA just needs to take the hand-applied foam off and replace it with a piece of metal to perform the same function. Heaters will prevent ice buildup.
The modifications don't require the creation of a new tank. NASA could modify an existing tank, such as the one they de-mated from Discovery.
Surprisingly, the STS-121 patch has not been released to the public. This may prove to be the last step before Atlantis can fly.
After STS-121 and the assembly of the truss, NASA should limit the shuttle to two crew change / resupply flights per year. The rest of the ISS modules can wait for SDV to come after 2011.
But the argument for J-2S is a good one two... a pair of them would give you similar thrust, and are not so far from production as you think... the linear aerospike engines for the X-33 were really a bank of eight J-2S engines with the nozzles cut off... this wasn't that long ago, and the original engine could be used as-is without modification. However, the old J-2 operates at relativly low Isp compared to SSME, so you would incur a substantial payload penalty (~15-20%!).
I think that the J-2S turbomachinery used in the X-33 engine testing came from components that were fabricated during the Apollo program. If I had to venture a guess, I would say that most of the J-2 / J-2S tooling is gone, even though at least a dozen engines are in storage (not to mention the engines sitting in museums.) In a worst-case scenario, it would be possible to reverse-engineer a J-2 series engine from the ones still in existence--but it wouldn't make fiscal sense.
An inline launcher is the obvious option, that to really seriously explore the Moon efficently you will need substantial payload to ride with the crew, and since the lander will be riding on the SDV, it absolutely needs to be bigger then "just enough" to repeat Apollo.
I suspect that the in-line option is gaining favor with the NASA leadership due to the continuing problems with foam shedding on the ET. Granted, the SDV cargo element is less vulnerable than the orbiter, but you still don't want to risk another fatal impact.
One aspect of the in-line studies that struck me was NASA's choice of a payload fairing that's smaller than the 8.4m diameter of the shuttle ET. Zubrin went with a larger fairing (10m) with Ares. Further, no mention is made in the studies about a side-mounted engine pod such as the one on Ares. I suspect that it was rejected out of hand because of the gross misalignment between the thrust vector and the velocity vector (which results in velocity losses.)
Griffin will be doing the right thing when he explains the moon-Mars planning to Congress. If he doesn't give them answers, they are less likely to give up the money that will be required to do exciting things in space.
I'd really like to hear how NASA intends on developing the "stick" launcher before 2011. The first stage is structurally complete, but the fuel grain needs to be redesigned to limit the accelerations on the astronauts. Stage 2 will be an all-new design that will require significant investments of time and taxpayer dollars. NASA might be able to save time if they commission Boeing to provide a stretched version of the Delta IV upper stage, with more thrust (either from multiple RL-10's, an RS-68, or an RL-60.) J-2S was a good engine but it may take forever to get production restarted. The SSME is way too expensive to put on an expendible rocket. Existing expendible engines are the way to go.
Regarding the Sietzen and Cowing articles, they helped me to realize the inefficiencies of the original Shuttle C and how it could be improved. The original Shuttle C Cargo Element had too much structure in common with the orbiter. An all-new payload shroud would be much lighter, and it could be cast off after the stack has escaped the lower atmosphere.
Agonizingly, the excerpts we're seeing on Nasawatch are from a book that won't be released until December. But I want it NOW!
It's hard to even begin picking this editorialist apart because he's got so many facts wrong. If he'd been paying attention, he'd see that Michael Griffin is accelerating the CEV, and it will fly in 2011. He's ignored the fact that most of the shuttle system is apparently being recycled to launch the new vehicle. And it's premature to say that the CEV will be an Apollo clone. It could be a biconic like the Russian Kliper, or it could be Lockheed's "lifting monstrosity."
As long as we have the burden of the space station to support, we have no choice but to use the shuttle for resupply missions until the CEV is ready to do the job. Europe's ATV has been slow coming down the pipeline, and even when it does enter service it will not be able to bring experiments back down.
The eventual CEV design could have a huge impact on ISS operations. If it can carry six people in one shot, the ISS could finally grow to its original six-man configuration. The cargo-hauling ability of the unmanned CEV will effect the amount of science that can be performed.
I suspect that the in-line SDV option will gain some momentum as a result of the ongoing foam problems. If a side-mount SDV is chosen, it will be vulnerable (albeit not as bad as the shuttle) to debris strikes.
The stuff on SpaceRef and NASA watch is quite good, and I look forward to reading the Cowing-Sietzen book when it comes out in December. Some of their info contradicts the Orlando Sentinel; SpaceRef shows a biconic spacecraft while the Sentinel has a pure capsule looking much like Apollo. I favor the pure capsule approach because it results in the lightest possible spacecraft.
I'm not too fond of the stick launcher, because you can't throttle the engine and the o-ring erosion problem is still a valid concern. Also, I suspect that it will require significant changes to the fuel grain to reduce the accelerations on the astronauts.
However, a study by SAIC claims that the acceleration forces for the stick are within limits, so this has eased some of my concerns. Another thing about the stick is that it won't be very hard to develop compared to a new design launcher (some would argue that it's easier to create the stick than it would be to man-rate the Delta and Atlas, but I would disagree.)
The Orlando Sentinel has gotten the scoop about NASA's moon architecture.
http://www.orlandosentinel.com/news/cus … home-promo
A lot of the pieces are starting to come together. The CEV will be launched by the stick, then dock with the Earth Departure Stage (EDS) and lunar lander. The lander will take four astronauts to the lunar surface for a week at a time, then perform a lunar orbit rendezvous and return to earth.
There are a few surprises in store. The lander will use methane-fueled engines, in anticipation of using the same engines for a future Mars mission. The EDS will use two J-2S engines, showing that it doesn't make sense to re-invent the proverbial wheel that was built for Apollo.
A few things have changed since Apollo. There's the rendezvous in earth orbit, a longer stay on the moon, and a bigger crew. The capsule will land on terra firma instead of water.
There are a few unresolved questions, like how NASA plans on using an expensive shuttle main engine for the expendable upper stage of the "stick launcher." How many crew members will stay in lunar orbit? I'm assuing that six astronauts will fly to the moon, with four landing on its surface and two staying in orbit. I'm also trying to figure out how reusable the CEV will be--I'm guessing that the heat shield will be good enough for one reentry from lunar velocities, or ten reentries from LEO.
Overall, Bob Zubrin SHOULD be happy with the mission architecture. He gets his shuttle-derived heavy lifter, he gets his small CEV, and NASA is clearly looking at a methane-fueled lander.
Let the intellectual 'battle royale' begin!
At this stage, the LockMart team is the underdog, and perhaps the recently-proposed "lifting monstrocity" is their attempt to innovate.
Northrop Grumman + Boeing has all of the experience wth manned spaceflight in the US. Mercury and Gemini were built by McDonnell--now part of Boeing. X-15, Apollo CSM, and the shuttle orbiter were built by North American Aviation--now part of Boeing. The LEM was built (quite magnificently, I may add) by Grumman, now part of Northrop Grumman. If these companies built on their proud and successful heritage, they could sleepwalk towards the CEV contract.
My preferred CEV concept is a capsule (the Big Gemini shape is preferred due to its increased volume, but it needs a docking tunnel in the nose first.) If additional habitation is needed, a small module could be added. The service module would resemble that on Apollo, but it would use solar arrays instead of fuel cells. The capsule would have airbags and landing rockets so it wouldn't have to land in the water. The LEM would be similar to the Grumman design, but it may have a spherical cabin like the Russian LOK. Propellants would be storable (Kerosene and either H2O2 or N2O) and non-toxic.
Shame on Lockheed Martin for dropping their gumdrop-shaped capsule that was proposed last year.
Titanium hull? Even Shuttle uses aluminum.
Titanium is actually a good thing. One of the findings from CAIB is that a heat-resistant crew cabin might have held toget
Over at Rand Simberg's site someone (not me) posted a great comment on the Lockheed CEV:
Its Kliper-iffic!
Actually, my assessment would be crap-tastic.
Obviously, an EELV-heavy will not be able to lift this monster in one throw. Perhaps it will be put up in two or three launches, but it will most likely be launched in one shot by an SDV. Apparently LockMart thinks that CEV is supposed to be some kind of make-work program for the shuttle army. People like me are shaking their heads in disbelief, saying that they should have aimed for Apollo redux.
Notably absent from the Lockmart drawing is any kind of lunar module. Sigh... It's not even clear where the lunar lander is supposed to dock.
The truth is that spaceplanes are only necessary for launching large crews or transporting people who cannot handle 4-5g re-entries. For the small crews that will initially be going to the ISS or the moon, a capsule will do just fine. Somebody pass this memo on to LockMart.
http://www.popularmechanics.com/science … l]Lockheed Martin's proposed CEV
Behold! A 70-foot-long stack with wings!
I'm highly disappointed. I thought Boeing and LockMart were supposed to be designing capsules, not doing OSP all over again. LockMart's CEV design is heavier and more complex than it needs to be. I hope Boeing's design is an improved Apollo, so that at least one of the teams designing the CEV hasn't fallen victim to idiocy.
A message to LockMart: keep it simple, stupids!
http://ap.washingtontimes.com/dynamic/s … E]Lockheed Martin, Boeing to form United Launch Alliance
So much for the idea of using competition to get a good deal for CEV launches.
Although I completely agree that Hubble should be replaced, it's clear to see that several things are happening that will ultimately save Hubble.
1) Hubble has the support of the media and the astronomers. With the media pressuring the politicians, there's bound to be an order from Washington to fix it. Further, we now have a pro-Hubble guy running NASA.
2) The death of Hubble will ultimately lead to a gap in coverage until the next space telescope (whether it be JWST or HOP) comes along. This is probably the best reason I can think of for prolonging Hubble's life.
3) HOP, while a good idea, is an unsolicited proposal that will probably not be taken seriously by NASA.
Hubble SM4 / STS-122 looks like it's going to happen. My biggest objection is one of safety. I would hope that if NASA does choose to fly SM4, it cancels several ISS missions in exchange. That way, the chance of a loss-of-crew accident is kept constant for the remainder of the STS program.
At the same time, NASA should not spend money on "Mir-2" concepts where the shuttle would carry an independent habitation module in case the shuttle is damaged. The utility of these concepts is of questionable value and even more dubious technical merit.
Buzz Aldrin is also not someone I reguard as being much more space savvy then any of us, he was mainly a pilot if memory serves.
Buzz earned an Sc.D in Aerospace Engineering from MIT in 1963 or so. His papers on the topic of rendezvous earned him the nickname "Dr. Rendezvous." Since his Apollo days he's been a bit of a space visionary; his ideas about space transportation range from zany to pragmatic.