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#26 2005-05-26 11:33:51
- clark
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
How would that work?
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#27 2005-05-26 13:00:14
- SpaceNut
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
Well I do not know about santa but any human surprise upon docking and opening the air lock would give all a fright.
The new science roadmap document[url=http://www.hq.nasa.gov/office/apio/pdf/srm2_mars_rdmp_final.pdf] A Roadmap for the Robotic and Human Exploration
of Mars[/url]
It discusses the need for heavy lift on pg. 8 under Technology/Capability Recommendations
Required:
• Hypersonic parachute to allow landing MSR-class assets at high elevations on Mars
• Human-scalable entry, descent, and landing systems capable of safely and precisely
landing large masses in units of up to 40 MT
• Heavy-lift launch vehicle (~100 MT to LEO)
o Validate on human lunar mission prior to first use for Mars
• Robust ~20-40 kW power plant for use on the surface of Mars
o Total power required may be approx. 60-100 kW; use multiple units for
flexibility and redundancy
o Advanced high-efficiency radioisotope power is required for robotic missions
• Validation of capabilities needed for human expeditions, using appropriate venue
o Strategically select opportunities to validate key capabilities in relevant
environments
o Includes Earth analog environments, ISS, Moon, and Mars (via robotic
missions)
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#28 2005-06-16 16:42:54
- publiusr
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
don't have a Delta IV that can launch 40 tons either right now revenger. Atlas V wide-body like angara beats that without solids.
That the SRB cannot be shut down wasn't the problem with Challenger. The fact it survived speaks to how rugged it is. Beats having a single RS-68 with no engine out having a Delta IV come straight back down on the pad.
I side with Griff--not with EELV huggers.
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#29 2005-06-16 17:55:01
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
As I've said before publiusr, getting to 40MT with Delta shoudln't be too hard, you get most of the way there by adding plain old in-production GEM-60 solid rocket motors and getting rid of the antique RL-10 engine on the upper stage. I would say that since these modifications are pretty minor, and the rocket has actually been test-flown, I think its fair to say that we do indeed have this vehicle.
Lockheed's tripple barrel rocket however doesn't exsist, and even if it did it would require just as much or more modification to reach 40MT as Delta would, so overall it would probobly be a bit harder to reach that point.
What you may have missed Publiusr, is that the specs for CEV call for a 20MT, preferably 25MT payload mass. This accounts for a ~6MT capsule, a few MT for the service module dry, and the rest for fuel (probobly Methane & LOX) sufficent to return to Earth from Lunar orbit or during Earth-Moon transit. Not 40MT.
SO, that puts the standard Delta-IV Medium out of the running without adding at least six SRMs, which I am not too happy about unless they were sturdy enough that you could lose one if it blew up. Lockheed however, very well could build a modified Atlas with a much more powerful upper stage (the current one is pretty puny) that could just do the job. And it would be liquid fueled. And it already flies... The other option, which I am not keen on either, is to add crossfeed to the Delta-IV HLV so it has partial engine-out, which would probobly be safe enough... It would work however.
Simply shrugging off the fact that a solid rocket booster failing would cause a huge explosion compared to a liquid fueled booster by just assuming it won't happen is nothing short of stupid. If that booster explodes, the chances the crew is going to survive are pretty slim versus a liquid rocket, which:
-Would be easier to detect impending engine failure
-Would be possible to avert impending engine failure
-Would not instantly destroy the entire rocket if the engine blew up
-Would not create as high a pressure shockwave if it ignited the fuel tanks, only higher temperature
-If you did have to abort and seperate, you could do so with much lower G-force and higher confidance of survival
Our rocket building technology is simply not sufficently developed to bet on the thing not blowing up ever. I think that is a pretty strong case for building "Atlas-VB" for CEV launch.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#30 2005-06-29 13:58:57
- publiusr
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
I am not worried about SRB explosions what with their very strong (dare I say solid) construction. They are therefore better at flying depressed trajectory than EELV--which must also have solids to improve their performance--and those solids are not encased in heavy steel--being more like the small solids like we saw explode that Delta II on that recent FOX special "World's Most Powerful Explosions."
More on the SRB/CEV combo here:
http://groups.yahoo.com/group/inside_ks … sage/11313
http://groups.yahoo.com/group/inside_ks … sage/11308
It seems SDV HLLV is gaining ground, as I mention here (lots of good links and artwork):
http://starshipmodeler.net/cgi-bin/phpB … ...#370599
Griffin tesified before the House yesterday--and they seem very impressed with his credentials.
This article is very interesting:
http://www.orlandosentinel.com/news/cus … ...s-space
Shuttle components could be used in Next Generation of Rockets
By Michael Cabbage
Sentinel Space Editor
June 27, 2005
{Edited}
CAPE CANAVERAL -- Discovery's planned launch next month will mark the beginning of the end of the space-shuttle program, but parts of the rocket could help propel astronauts to the moon and beyond long after the current fleet of ships is retired....
The likely solution: launchers created from parts of the so-called shuttle stack that includes the external fuel tank and twin solid rocket boosters.
A shuttle-derived booster would have lots of advantages besides its ability as a heavy lifter.
The shuttle's components are considered safe for human missions. Many of the facilities to build, process and launch a new vehicle already are in place. The time required to develop a shuttle-based booster would be a relatively short four to five years. Many shuttle workers at places such as Kennedy Space Center could continue on in the new effort.
"The shuttle-derived answer is significantly better in terms of the work force at the Cape [Canaveral]," said Steve Oswald, a former astronaut and Boeing vice president who heads the company's shuttle efforts.
"If the requirement is for great big pieces to go to orbit, the shuttle-derived vehicle is it," said Mike McCulley, president of shuttle prime contractor United Space Alliance and a former astronaut. "I'm not criticizing either the Atlas or the Delta, but they have their limits. . . . If you start with a new rocket, it's years and billions [of dollars]."
A new study by NASA and shuttle contractors made public during an Orlando space-exploration conference in January identified several basic designs that could put people and cargo into orbit. One design would use one of the shuttle's twin pencil-shaped solid rocket boosters as a first stage, with a new manned vehicle or cargo carrier and a second stage perched on top.
However, NASA is getting pressure from the Pentagon to use the Delta and Atlas fleets for some of its future missions. The financially struggling rocket lines badly need another government customer in addition to the Air Force.
(Ah--the financial pressure to hack EELV shows itself)
Griffin has said cost would be the biggest factor. However, he and others continue to hail the safety record of the shuttle's solid rocket booster.
Cheaper, expendable main engines would be developed to replace the costly reusable versions on the shuttle. Engineers estimate the rocket would be capable of hauling a hefty 100 tons to an orbit 250 miles high.
Another, more powerful shuttle-derived design would modify the tank to put four main engines beneath it and a cargo carrier with a second-stage engine on top. The colossal 36-story launcher, which would look similar to traditional expendable rockets, also would be equipped with larger solid rocket boosters than those presently used on the shuttle.
This so-called in-line heavy-lift rocket could launch an estimated 120 tons to orbit. It would rival the Saturn 5 as the most powerful booster ever.
"If you did the in-line heavy, you could just duplicate Apollo," said Oswald, explaining how a manned moon mission might work. "You could do it all in one launch."
"If you end up using the side-mount [design], you probably are going to need to launch some piece of that with something else," he added. "If you were going to go to Mars, you might end up needing two or three [launches] to get going, but that's better than 10 or 12."
BINGO!
And the last nail has been (hopefully) driven in EELV's coffin.
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#31 2005-06-29 14:32:14
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
That is true, the big SRB is built pretty strong, but more importantly (if it can be believed) is that the Thiokol people claim that if the booster were to breach, that the fuel itself won't burn efficently when it loses chaimber pressure... Although this is a nice safety feature, I am still not convinced that the high operational and escape G-forces are acceptable for an SRB launcher.
You seem to be getting the light EELVs and the medium EELVs mixed up, Publiusr: only the cargo 50MT version would need solid rockets, but Lockheed's Atlas-V with a single core and some upgrades is powerful enough to launch the CEV without any solid rockets at all. Zero. The Delta-IV HLV, with crossfeed fuel lines, would have partial engine out ability too which would probobly make it safe enough in a pinch, though that would only be a fallback.
"Many shuttle workers at places such as Kennedy Space Center could continue on in the new effort... The shuttle-derived answer is significantly better in terms of the work force at the Cape"
Which is exactly what we ought to be trying to avoid. I am very wary that NASA, even with Griffin at the helm, can't resist trying to gradfather in the Shuttle Army. If they fall into this temptation, then the whole matter should be made moot by eliminating the entire Shuttle program and going with EELV.
Financially, they would have a hard time competing with bulk orders of EELV, shared between the USAF and NASA, which would go a long way to avoiding the problem of flight rate, and this is a serious advantage... The Army keeps drawing a salery if they are launching rockets or not. If NASA can't reform its ways on its own, then they need to be forced to do it, which means EELV.
""If you end up using the side-mount [design], you probably are going to need to launch some piece of that with something else," he added. "If you were going to go to Mars, you might end up needing two or three [launches] to get going, but that's better than 10 or 12.""
Again, repeating the old "EELV = 25MT" lie, this refrain is getting tiresome...
Anyway, again I would like to point out the limitations of side-mounting:
-Signifigantly less efficent
-No escape velocity missions
-Limited payload diameter
This last point especially, if you are going to build a REAL Mars ship and not Bob Zubrin's cramped sardine can, then you are going to need more then a 6m diameter faring like Shuttle-C. And that means in-line launch.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#32 2005-07-14 16:34:13
- JonClarke
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
GCNRevenger wrote:
"This last point especially, if you are going to build a REAL Mars ship and not Bob Zubrin's cramped sardine can, then you are going to need more then a 6m diameter faring like Shuttle-C. And that means in-line launch."
For the ercord:
Zurbrin's Ares concept is inline.
The Mars Direct hab module is 8 m in diameter, not 6.
The hab is not particularly cramped, with at least 50 m3 of pressurised volume per person for a 4 person crew.
It is also worth noting that while 6 m is on the narrow side for a lander that sits vertically on the surface, it is not too narrow for a horizontal lander, in fact it is larger than what is needed (more like 5 m).
Jon
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#33 2005-07-14 18:52:41
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
The MarsDirect HAB module is 8m, but the ERV isn't, its only like 6m wide if memory serves. In any event, I was pointing out that Shuttle-C couldn't accomodate Zubrin's MarsDirect vehicles (not talking about Ares here), since it can't handle payloads bigger than 6-7m in diameter. NASA DRM calls for a ~8m minimum diameter.
"The hab is not particularly cramped"
Have you looked at the diagram for the HAB? Its so tiny! Four people living in the space smaller then a decent one-bed apartment on Earth. All that volume on the lower deck will be useless too, since it will be taken up by equipment (including the big rover and probobly the nuclear reactor & truck) and the MarsDirect airlock (big enough for vehicles). I think that this is plainly unacceptable, and both larger contiguous volumes plus more space per crewman is a nessesity.
The NASA DRM mission has ninety cubic meters per crewman, and thats with six crew and larger open areas, not subdivided into little closets like MarsDirect. The DRM HAB has three decks, two 8m wide ones plus a smaller "basement" deck with storage, space suit racks, and the airlock/docking port.
The MarsDirect ERV is a non-starter too, unless you cut the crew down; even Bob thinks that this is a weak spot in the plan.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#34 2005-07-14 19:18:31
- Yang Liwei Rocket
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
The NASA DRM mission has ninety cubic meters per crewman, and thats with six crew and larger open areas, not subdivided into little closets like MarsDirect. The DRM HAB has three decks, two 8m wide ones plus a smaller "basement" deck with storage, space suit racks, and the airlock/docking port.
The size is ninety meters ? For some reason I thought it was much bigger that doesn't seem great much you compare to the MIR station, Apollo, the Salyut, the ESA Aurora-Mars mission options, TKS Manned Ferry complex, ISS or USAs Skylab or the Russian Mars-Station Model. Anyway GCNRevenger when you talk about these projects you should perhaps quote the total weight of the payloads, describe the internal living volume in cubic metres, and the Total volume of the craft modules on the Mission
The Mars mission that NASA is looking at and the designs I've seen are very good, internal living space would not be a problem. It's the cost of such a project, NASA has already been making budget cuts and questions about if the science and design is ready for such a risky mission and people have asked about the safety of such a journey.
'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )
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#35 2005-07-17 05:00:40
- JonClarke
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
The Mars Direct (MD) habitat module is 8 m in diameter and 8 m high, with a volume of 400 m3. Thus with a 4 person crew there is 100 m3 per crew member. This compares favourably with the NASA DRM habitat module which 500 m3 of volume allows only 83 m3 per person for a crew of 6. But both these numbers are at the high range compared with those of historic spacecraft. Salyut 7 with a supported 3 people for more than 6 months at a stretch with 108 m3 of volume, Mir a similar number for missions of over a year on 284 m3, thus 34 and 91 m3 per person respectively. So volume wise, 80-100 m3 per person seems quite acceptable.
Of course the crew of a MD habitat will spend most of its time in gravity, thus floor area rather than volume is perhaps a better measure of habitability than volyme. The MD habitat module a floor area of 100 m2 spread over two decks. While there indeed larger apartments this floor area is about the same as many 3 or 4 bedroom houses. It is very generous I suspect compared to many of the small historic Antarctic bases and submarines. So 100 m2 would also be acceptable.
No disagreement that the MD ERV as specified is too small. But there are several solutions to this problem.
Jon
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#36 2005-07-17 07:27:34
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
"The Mars Direct (MD) habitat module is 8 m in diameter and 8 m high"
But it isn't! The entire lower deck of the MarsDirect HAB will be unuseable during the trip to Mars because of all the equipment that must be stored on the lower deck and the large (rover sized?) airlock (likly with rover in it). And when you do get to Mars, you aren't probobly going to make the airlock your rec room either, plus the other half of the lower deck will have to accomodate space suits and related equipment. Probobly food/water and sample storage too.
NASA DRM on the other hand, both decks are completely dedicated to the crew for the entire trip, with vehicle of essentially identical size for the ERV, plus has a third "basement" deck for storage, suit room, and airlock/docking hatch.
MarsDirect's HAB is deceptively small despite its size... And the best way to fix the ERV size problem is to not bring it to Mars to begin with, since you will have to lift it off the surface later, but instead leave it in Mars orbit.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#37 2005-07-17 16:35:46
- JonClarke
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
"The Mars Direct (MD) habitat module is 8 m in diameter and 8 m high"
But it isn't! The entire lower deck of the MarsDirect HAB will be unuseable during the trip to Mars because of all the equipment that must be stored on the lower deck and the large (rover sized?) airlock (likly with rover in it). And when you do get to Mars, you aren't probobly going to make the airlock your rec room either, plus the other half of the lower deck will have to accomodate space suits and related equipment. Probobly food/water and sample storage too.
NASA DRM on the other hand, both decks are completely dedicated to the crew for the entire trip, with vehicle of essentially identical size for the ERV, plus has a third "basement" deck for storage, suit room, and airlock/docking hatch.
MarsDirect's HAB is deceptively small despite its size... And the best way to fix the ERV size problem is to not bring it to Mars to begin with, since you will have to lift it off the surface later, but instead leave it in Mars orbit.
900 days of consumables using the consumption and recyling assumptions of MD mass 7 tonnes. Assuming a packing/storage of density of 0.5 (which I suggest would be pessimistic) this would occupy 14 m3.
Assuming 2.5 m deck spacing two decks occupy 250 m3 of the 400 m3 pressurised volume of the hab. This leaves 150 m3 of presurised volume available for consumable and other storage. Even if all stored on the two living decks this would be only 6% of the total volume.
I agree the Mars semi Direct architecture is a very attractive option, and I have used this in a published mission scenario. But But a superior mars hab volume isn't the reason for it's attractiveness.
Jon
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#38 2005-07-17 18:33:58
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
There probobly is enough room for "bilge" storage in either MarsDirect or DRM, but my bigger issue is the pressurized rover... where exactly does it fit in the MarsDirect HAB? If the thing is at least 2.5-3.0m wide and twice that long, then the airlock will consume the majority of the lower deck of the HAB. Add in storage for things that are bulky and won't fit in "bilge" (space suits, drilling rig, sample storage, etc) and the lower deck is pretty much lost to the crew. Also, where do the unpressurized rovers and the nuclear reactor ride? Will they fit in the "skirt" around the landing gear astride the lander tanks/engines?
I think that the larger size of the NASA DRM hab module is quite attractive, particularly with the potential for larger contiguous spaces (that submariners love) and is one of a variety of reasons that it trumps MarsDirect cold.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#39 2005-07-18 03:11:15
- JonClarke
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
Rover storage is an interesting issue. I don't think any of the DRM incarnations address it either There actually lots of issues about rovers that are fudged or glossed over in both MD and the DRM. probably not critical to the pruposes of these studies but they need to be addressed sometime, and a few people have.
With MD I suggest the best place would be underneath the pressure hull. if this makes the whole struck too high then the height of the pressure hull might have to be reduced. As the hull is 8 m high and two decks would only occupy 5 m, I think there is volume to spare for this.
As far as I can tell (without them in front of me) the different incarnations of the DRM all have about 500-540 m3 volume, which is only about 20-35% more than the DRM. Since the DRM has 50% more crew there is actually less space per person than with MD, although I don't think the difference is crucial. It is worth noting that the hab in version 1.0 of the DRM was 7.5 m in diameter, slightly smaller than MD's 8 m, although again this is not significant.
I agree that least some large internal spaces are desirable for crew well being, although I haven't seen any literature that specifies how large the spaces might have to be. Sincenone of the DRM literature I have seen shows and internal layout and the MD hab layout is conceptual, a wide range of possibilities exist. I suspect that some form of reconfigurable interior is also highly desirable.
On another matter you said earlier than the DRM had had three full decks. This was my recollection also, but version 1.0 has only two decks, and I was not able, in a quick scan at least, to locate a mention to three decks in the in version 3.0 document. Suggestions appreciated.
Jon
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#40 2005-07-18 08:14:31
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
http://exploration.jsc.nasa.gov/marsref/contents.html
http://ares.jsc.nasa.gov/HumanExplore/E … ...m#Title
Actually they do, or at least moreso then MarsDirect... the long range rover would be carried in a cradle under the MAV, as per page 3-109. There should be enough room to accomodate a unpressurized rover or two under the pressure hull next to the fuel tanks.
And an 8m high HAB is more of a nessesitty for MD then you think, it needs that extra ceiling space for the aerobrake shield contour, parachutes, etc and the "bilge" space under the floor for the life support systems and storage, particularly for full redundancy and spare parts. I doubt you could squeeze a whole meter off its height.
Both DRM-I and DRM-III have three-deck HABs, with the airlock as a small "basement" deck visible on 3-85 and sketched on 3-111 in DRM-I with room for six suits and an airlock big enough for two crewmen. It is again seen in DRM-III section A2 in the "home made" 3D rendering with the extended inflatable lab.
If you want a copy of these documents, I suggest that you save them to disk, since NASA has a bad reccord of retaining old pages.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#41 2005-07-18 10:31:10
- RobertDyck
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
Don't confuse Mars Direct as published with the analog stations. Mars Direct has a single upper deck during transit to Mars, as published in "The Case for Mars", 1997, and a coloured version in Scientific American, March 2000. Floor plan http://www.marssociety.org/images/direc … 1.gif]here. A floor plan of the lower deck wasn't detailed, it was just storage. A painting http://www.marssociety.org/images/full/ … 1.jpg]here shows Mars Direct on the surface of Mars with all equipment deployed, including the habitat with a garage door in the lower floor.
![http://www.marssociety.org/images/direc … 1.gif]here](http://www.marssociety.org/images/direct/marsd11.gif]here){kind=link}
![http://www.marssociety.org/images/full/ … 1.jpg]here](http://www.marssociety.org/images/full/surface1.jpg]here){kind=link}
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#42 2005-07-18 10:40:37
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
I am reluctant to take the artists' drawings of MarsDirect with the "garage" jumbo airlock as canon, but I don't know where else you are going to put the thing... the HAB is too low to the ground to slip it under the bottom bulkhead, and the ERV needs every single gram of mass (and then some) for the return trip.
Also to note, the "pointy" DRM-III HAB has more potential storage space above the pressure hull, perhaps even for landing fuel so you can use the entire "skirt" sans engines for ground equipment (rover(s), drill, reactor). Does MarsDirect have this?
Edit: Oh, and if there is a big centerline garage, then the MD sketch showing the ladder going down to the lower deck won't work... Plans for MD's final design seem pretty nebulous to me, if the current "advertised" version won't work.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#43 2005-07-18 11:08:03
- RobertDyck
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
NASA's Design Reference Mission has at least 3 versions, so why are you surprised Mars Direct does as well? Mission architecture hasn't changed, just details like floor plan. They moved the ladder to the side instead of centre and moved the airlock to the lower deck. By the way, the floor plan I linked is from the book by Robert Zubrin and Richard Wagner; I think that's authoritative enough.
::Edit:: The original version had the airlock in the centre of the upper floor. The lower floor was unpressurized storage. Later versions moved the airlock to the side of the lower floor so the lower floor could be pressurized after the rover and surface equipment were moved out.
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#44 2005-07-18 16:37:49
- JonClarke
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
Thanks for the page references, I have saved the reports, I just don't have them here.
DRM 1.0 has only two full decks, as I said. A lower level airlock does not count as a full deck, in my book at any rate. By the sound of it version 3 is the same. I don't see why the MD hab cannot have the same arrangement as the DRM with a lower level airlock and external storage of equipment, provided mass and stability constraints are maintained.
But the internal layouts of all of these are conceptual. Rather than saying that something is impossible, it is more useful to see whether it is possble within the constraints.
Of course not everything is possible, as I have said, the MD proposed ERV is too small, But this is a criticism of a particular proposed mission (MD, it does not mean that the md architecture (note lowercase) is unworkable, only that modification is required. One modification is the msd architecture, one particular interpretation of which is MSD and the DRMs. Other solutions are possible.
Jon
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#45 2005-07-22 12:13:09
- publiusr
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
Now RAND is trying to kill HLLV:
http://xprizenews.org/forum/viewtopic.php?p=15503#15503
scroll on down.
There are three HLLV programs being looked at:
In French
http://forums.futura-sciences.com/thread25593.html
1.) The Euro-HLLV (100 tons to orbit--not 41 as I thought before)
http://www.marssociety.de/emc/proceedings/Ferra.pdf
2.) The American SDV/HLLV also known as Ares, Magnum, BMDO Launcher, etc.
http://www.spaceref.com/news/viewnews.html?id=1040
http://www.safesimplesoon.com/heavylift … vylift.htm (click on charts and visit the media center)
3.) And the Angara 100.
http://www.russianspaceweb.com/angara100.html
http://www.russianspaceweb.com/tks_followon.html
Most likely...ATK's shuttle derived heavy-lifter
Least likely...Angara 100
Dark Horse...Ariane M
Three choices for Heavy-Lift:
Ares, Ariane-M and Angara 100 The AAA of the future.
At least people are talking about more adequate rockets.
http://www.flatoday.com/apps/pbcs.dll/a … 007/news02
I don't see EELV launched habs being anything other than less roomy than HLLV launched vehicles with wider diameters for larger rigid or inflatable structures.
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#46 2005-08-16 05:56:44
- SpaceNut
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
From Mars society conference as post in Mars Society International
Woodstock of Mars
A journalists review of the Mars societies conference 2005
as posted by John Creighton:
The next to speak was former Shuttle commander Dr. Scott Horowitz,
now with ATK Thiokol, who presented his ideas for a new generation of
launch vehicles based on Space Shuttle technology. The concepts
include a 130 tonne to LEO heavy lift vehicle (HLV) employing two 5-
segment solid rocket boosters (the current Shuttle uses 4-segment
SRBs) and 5 space shuttle main engines (SSME) in the first stage,
with a Shuttle external tank providing the first stage core, and a 9-
meter diameter payload fairing including a hydrogen oxygen upper
stage powered by 1 SSME mounted above. In Horowitz's plan, this
vehicle would deliver all the heavy cargos needed to go to the Moon
or Mars to low Earth orbit (LEO). The crew would then be delivered to
orbit in a capsule CEV on a medium launch vehicle (MLV, 20 tonne to
LEO capacity) composed of a single 5-segment SRB with a hydrogen
oxygen upper stage powered by 1 SSME.
So a total of 6 SSME per rocket with the extra segment SRB's which have all been tested only to get the payload to LEO. You would need another stage to get the cargo to the moon once in orbit would we not?
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#47 2005-08-16 12:13:36
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
No, the upper stage with the SSME would provide the burn to get to the Moon
130MT might be a little overkill, but if NASA can get SSMEs cheaply (say, half of current price) then this would be practical.
I think SSME is probobly a better choice for The Stick with its much higher performance.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#48 2005-08-17 05:38:28
- SpaceNut
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
So that means that we are hauling what would have been the ET all the way to orbit still firing before we final release it? Gee if so SpaceIsland would like to hear that.. 
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#49 2005-08-17 06:53:02
- GCNRevenger
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
No, the upper stage will still be used for the final orbital insertion and circulization burns, the big main tank won't reach a stable orbit.
Even if it did, Space Island are fools to think that the tank is worth anything.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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#50 2005-08-17 13:47:03
- Dragoneye
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- Registered: 2005-08-17
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Re: The Myth of heavy lift 2 - (Let the fight find a new home)
they should work on propultion systems more so they can get more vehicles that are reusable for heavy lifting.... they had some great technology going on one of the X planes they stopped research on.... In all honesty private research is cheaper and better as far as getting new and innovative ideas out there.
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