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#51 2006-07-31 08:54:32
- GCNRevenger
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Re: CEV is Bullshi...
The only time we need a reentry shield is for earth atomsphere descents
No. There is one other time, which is in the event of an emergency return to Earth from the Moon or transit to/from it. Apollo-XIII for instance would never have been able to synchronize orbits, dock, and transfer with a hypothetical space station if their vehicle didn't have a heat shield/parachutes/etc.
A one-piece reuseable lander will be expensive to develop, but probably not be all that expensive to build in number. Why is disguarding it such a bad thing? In order to supply fuel for each trip to the Moon, you would need to send up a medium class (40-60MT aprox) rocket and a tanker. You can either throw away the lander or you can throw away the tanker, but if you go with the expendable lander you only have to develop one vehicle instead of two. You would probably get a higher maximum payload too, which would be critical for base building. Oh, and you would need to launch two different rockets, or 3-4 smaller rockets for each Lunar sortie, so there isn't much savings there either. Nobody has ever demonstrated any ability to perform much in the way of maintenance in zero gravity either.
[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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#52 2006-07-31 14:52:04
- RedStreak
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Re: CEV is Bullshi...
A one-piece reuseable lander will be expensive to develop, but probably not be all that expensive to build in number. Why is disguarding it such a bad thing?
You can either throw away the lander or you can throw away the tanker, but if you go with the expendable lander you only have to develop one vehicle instead of two. You would probably get a higher maximum payload too, which would be critical for base building.
Why is throwing away a lander a good thing at all? We've been throwing stuff away in LEO alone for long enough that the ISS and even satellites have to periodically monitor space garbage. Is it REALLY any better to start spewing junk in Lunar space especially when we don't have the benefit of a tracking station there? Also surely there's ways to utilize the equiptment...at the least the lower half of a disposable LSAM, already on the moon and in a surveyed area, could be used as an LOX tank.
Anyway the point of a resuseable lunar lander is to reduce the need of launching equiptment. You have a good point on "resuseable tankers" and the problems they generate...which brought me to a solution that ought to have occured to us all earlier.
Why not use the CEV, and yes even a CREWED CEV, itself as the tanker?
I noted several problems related to the concept of a Reuseable LSAM (or RLSAM)vehicle that brought this idea to me:
1) Refueling - even if LOX is developed there's still the need for either H2 or CH4 and we can't bet exclusively on lunar water ice nor utilize it in the short-term.
2) Tanker Vehicles - even if the RLSAM is reuseable, the architecture needed for a tanker (particularly if it is expendable) undermines the merits of a RLSAM and overcomplicates the project.
3) Servicing issues. Roughly a quarter of a million miles makes fixing the Hubble in LEO look like trip to a car wash.
Now why use the CEV? Or how as a refueling vehicle?First off its already designed to rendevous with the LSAM. Its only lacking point is it is dependent on the LSAM and EDS (Earth Departure Stage) to reach the moon. It can (or ought to be able to) carry cryogenic fuel. Thirdly it itself is a manned vehicle - if servicing is thought to be required a short spacewalk ala Hubble is possible...especially since the LSAM has an airlock for egress even if the CEV doesn't. As for the worries over a fuel-line next to an airlock, well the Progress ALSO carries fuel and yet it too sports an airlock for astronauts to reach their goodies...
Now here's my senerio:
The RLSAM would be single stage - a one-piece vehicle. Larger fuel tanks to carry the total fuel volume for descent and ascent but the fuel required would be little different than for the two-stage LSAM. The need for only one set of engines would offset any mass difference. Keep in mind the RLSAM is for a crewed vehicle - a cargo LSAM would land on the moon but I doubt there's any need for one to take off again.
The CEV/tanker, which I'll call CEV2, would have the same command module, same dimensions although future variants (such as for Mars) could be scaled up. Its service module would be modified however to carry the fuel required for the RLSAM - just the fuel not the oxidider; that portion would be lunar-generated. A CEV2 would be launched via the Ares-V as well (it has been mentioned in numerous reports that the Ares-V WILL be considered as an optional manned vehicle so this is not unreasonable). It'd take the place of the LSAM atop the EDS. The rendevous would occur exclusively in Lunar Orbit instead of LEO.
Here's the launch plan itself:
1) An RLSAM is brought up in a more or less normal VSE flight plan. Instead of being disposed it instead remains in Lunar Orbit with a load of LOX sufficent for a Lunar Descent.
2) A CEV2 is launched carrying sufficent fuel & LOX for itself and also fuel for a complete RLSAM ascent/descent.
3) The CEV2 and RLSAM rendevous in lunar orbit. Once docked if deemed nessicary a space walk is done. A small fueline would perform the fuel transfer to the RLSAM.
4) The RLSAM uncouples and lands, performing the required mission. It refuels its LOX fully while on surface.
5) The RLSAM ascends, using up its remaining fuel to enter Lunar Orbit and rendevous w/ CEV2 but retains sufficent LOX for a future descent.
6) The CEV2 undocks and returns to Earth while the RLSAM awaits its next flight.
It involves modifying both the CEV and LSAM but, especially if you want a Mars mission or a more advanced lunar one, modifications like this would be nessicary, and for the most part all that is physically modified are the fuel tanks.
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#53 2006-07-31 15:43:37
- GCNRevenger
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Re: CEV is Bullshi...
This is not a bad idea, but it has some drawbacks, particularly safety ones: Crews riding on Ares-V is a bad idea, and should only be considerd if the sucess of VSE is in jepardy. No amount of refinement is going to fix this, the problem remains that you are putting people on top of a rocket with segmented solid rockets astride a huge take of fuel. Ares-V itself would be a little overkill for this mission plan too.
Instead, if we have a supply of LOX on the surface and you don't mind sending large cargo loads with expendable landers, then send a large shipment of liquid hydrogen for the lander every now and then that way. The same tank could be reused for LOX storage or perhaps even pressurized housing/workshops/etc later on. In this case, two Ares-I rockets would be launched, one with CEV and one with a miniature EDS stage (just an Ares-I upper with extended fuel tank perhaps) for transit to Lunar orbit.
No CEV modification, no zero-gravity fuel transfer, no zero-gravity maintenace. Do all the lander refuelling and maintenance at the Lunar base.
This all stringently hinges on the availability of Lunar oxygen, if we don't yet have that, then we are better off using expendable landers until we do.
[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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#54 2006-07-31 17:22:03
- RedStreak
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Re: CEV is Bullshi...
Hmmm...so you suggest fuel storage on the moon itself? I'll admit that wouldn't require modifying the CEV and it goes along with the RLSAM idea.
I'll put this stuff in the LSAM forum...
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#55 2006-07-31 19:46:18
- Martin_Tristar
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Re: CEV is Bullshi...
Firstly,
GCNR, I didn't say to launch all the rocket / mission from earth, but to have a lunar transfer vessel in orbit connected to the ISS or sitting close to the ISS. I mean to launch from earth orbit the lunar transfer vessel to the moon and have a one stage lander to return to a larger reusable service module for the transfer back from the moon. Then the CEV Command module would return to earth from Low orbit using the Ares 1 Vehicle to LEO only.
This reduces the costs for space launches from using Ares V - HLLV for routine lunar launches decreasing those launch costs. What we use the Ares V is to increase the large orbit components for the station or building a second station or large interplanetary probes or surface droid missions. ( example - Mars GPS and Comm Satellite Package for mission expansion )
We need the launching of cargo and crews, must be in a reusable vehicle that reduces te overall cost per mission. If we need to develop a Ares 3 launch vehicle based on the Saturn 1B then we should, ( using the first stage of Ares V to reduce development costs ) thus providing the 60MT payload launch vehicle for LEO cargo vessels and larger crew vessels and large combination cargo / crew hybrid vessels then the Ares 1 can carry.
American Space Vehicle Fleet :
Ares 1 - Crew Launch Vehicle with small cargo volume for space station
and low earth orbit
Ares 3 - Larger Crew and /or Cargo Vessels for space station or translunar vehicle resupply.
Ares 5 - Heavy Lift Launch Vehicle (HLLV) Multi-purpose use including modules for space stations or modular vessels, launching large satellites and interplanetary probes /and surface droids
Other countries like Australia, Japan, South Korea, Canada, Britain and even the Europeans could build the payloads (crew / cargo vessels ) for getting into space while the United States could be the launch vehicle thus increaing the use of the platform reducing the recovery of costs and increasing space faring nations throughout the world.
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#56 2006-07-31 20:00:38
- GCNRevenger
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Re: CEV is Bullshi...
Hmmm...so you suggest fuel storage on the moon itself? I'll admit that wouldn't require modifying the CEV and it goes along with the RLSAM idea.
I'll put this stuff in the LSAM forum...
It does tend to simplify things when you have solid ground under you too... there is a propellant penalty though with landing the Hydrogen on the surface as opposed to leaving it in orbit, but with Hydrogen on the surface you can make short suborbital trips to sites far away from the base without needing a full Earth-Moon sortie.
[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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#57 2006-07-31 23:03:36
- RedStreak
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Re: CEV is Bullshi...
Martin I dunno if an interorbital vehicle like your suggesting is nessicary. Its better to use the heavy lift and get the transluna stage with the cargo at once, especially if the fuel used is cryogenic. Its a bit of a waste of time and money waiting for a tug or to rendevous with a booster rocket.
We need to minimize what needs to be brought up. If anything is to be learned from the woes of the space station is that building something too huge tends to blow back up in your face. That is why I advocate for a reuseable LSAM at least later on in the VSE, so fewer landers need to be launched.
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#58 2006-08-01 03:55:02
- Martin_Tristar
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Re: CEV is Bullshi...
RedStreak,
We need to establish a long term view of launches to the moon and the L points for Moonbase Development or maintenance of space objects including all the telescopes and other observatories. If we look at the throw-away ideas of the Saturn -Apollo tourist missions as our guide for Ares Platform then we won't get anywhere with the CEV as well. By standardizing on the heavy lift vehicle - first stage of Ares V and design 60-130MT Lift vehicles for a variety of tasks then we could expand the frontier for humanity.
We need a structured approach designed for multiple missions to the moon and expansion of the space station into multiple platforms with a variety of tasks using the skylab workshop design as a blueprint for commercial platforms with bigelow habitats as expansion modules.
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#59 2006-08-01 04:32:54
- RedStreak
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Re: CEV is Bullshi...
RedStreak,
We need to establish a long term view of launches to the moon and the L points for Moonbase Development or maintenance of space objects including all the telescopes and other observatories. If we look at the throw-away ideas of the Saturn -Apollo tourist missions as our guide for Ares Platform then we won't get anywhere with the CEV as well.
What I'm thinking about is something practical for the near-to-intermediate future. At the least I have in mind a Reuseable LSAM to cut down on equiptment launched, at least for crewed vehicles, and modifying the CEV for wider applications.
Utilizing the Lagrange or L points isn't a bad idea, but we need to remember the lessons learned from the ISS. A moon base with LOX production capability is a higher priority than interorbital vehicles or any type of platform like a lunar space station. I'm trying to take a horse-before-the-carriage POV.
I believe the current VSE and its vehicles will be nessicary for the initial implementation but once a working lunar base comes into being then and only then should we begin reworking the nessicary lunar architecture and even then something akin to the Mars Direct approach is the most economical.
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#60 2006-08-11 15:49:58
- publiusr
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Re: CEV is Bullshi...
I have no problems with the crew riding Ares V.
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#61 2006-08-16 12:27:37
- Tom Kalbfus
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Re: CEV is Bullshi...
May I be the first to say how bullsh*t this new CEV craft is. First off, we shouldn't make a jack-of-all-trades spacecraft, it's just bad principle. Space, as a term of destination, remember, is a huge generalisation. If space is anagolous to the ocean then it would be sufficient to describe the CEV as a boat. It is simply an airtight vessel capable of transporting stuff from one destination to another. Which does nothing at all to describe its capabilities, other than it's capable of being a boat. Is it a short range passenger ferry, a small dinghy, or a disposable life raft, or perhaps a house-boat? The CEV's purpose needs to be set in concrete before we start thinking about the design and funding and such. And what of this nonsense about accelerating the design schedule? Why must NASA insist on a 24/7 human presence in space? Why? Can we even afford it anyhow? I mean look at the year 2013: The CEV will be absorbing maximum funding (operational vehicle or not), the ISS will still be occupied with a full-time crew, all the while the Moon program will be demanding huge sums of money. We simply can't afford all three pursuits. We have to drop atleast one, preferably two. The ISS should go ASAP, so why can't we kill it in 2010, with the shuttle? That way we wouldn't need to accelerate CEV development, which we couldn't afford anyway, and we can put full effort into the Moon-Mars program.
We already have the ISS to hold us back, we don't need the CEV to justify the ISS when it is complete; It'll be just another shuttle. Pointless mutual justification. Kill them both and concentrate on a dedicated 'Moon vehicle', not CEV.
How do you make a dedicated Moon Vehicle? Even the Apollo Capsule wasn't a dedicated Moon Vehicle, as it docked with Skylab and the Soyuz Capsule in 1975.
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#62 2006-08-17 22:03:49
- Martin_Tristar
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Re: CEV is Bullshi...
Tom Kalbfus,
I agree with alot of your comments regarding the CEV Design, we need to look at the design from a launcher component and payload vessel component. Development of Payload Vessels need to be specific to the needs of the task involved such as Non-Atomspheric Landings vs Atomspheric Landings or Cargo transfer into orbit vs Cargo returns from orbit. Each of these vessels require different requirements and systems to function in space and from earth to space.
Also, Allows the development of private support / logistics vessels for orbital platforms including the ISS. We could design the CEV Vehicles for Ariane / Falcon 9 and other launcher suppliers or develop a docking module for CEV developers to include the other launcher suppliers globally. Its time the private enterprise build and expand commerical applications / services in orbit and provide a return cargo system for commercial manufacturing processes for LEO Activities.
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#63 2006-08-18 17:25:24
- GCNRevenger
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Re: CEV is Bullshi...
GCNR, I didn't say to launch all the rocket / mission from earth, but to have a lunar transfer vessel in orbit connected to the ISS or sitting close to the ISS. I mean to launch from earth orbit the lunar transfer vessel to the moon and have a one stage lander to return to a larger reusable service module for the transfer back from the moon. Then the CEV Command module would return to earth from Low orbit using the Ares 1 Vehicle to LEO only.
This reduces the costs for space launches from using Ares V - HLLV for routine lunar launches decreasing those launch costs. What we use the Ares V is to increase the large orbit components for the station or building a second station or large interplanetary probes or surface droid missions. ( example - Mars GPS and Comm Satellite Package for mission expansion )
We need the launching of cargo and crews, must be in a reusable vehicle that reduces te overall cost per mission. If we need to develop a Ares 3 launch vehicle based on the Saturn 1B then we should, ( using the first stage of Ares V to reduce development costs ) thus providing the 60MT payload launch vehicle for LEO cargo vessels and larger crew vessels and large combination cargo / crew hybrid vessels then the Ares 1 can carry
No. The problem with this one is really very simple, it doesn't save anything, a reuseable Earth/Moon ship still requires fuel, LOTS of fuel. It doesn't save you any rockets, you still need fuel to leave Earth orbit, enter Lunar orbit, land, launch, leave Earth orbit... but now in addition you also need to burn fuel to enter Earth orbit instead of direct reentry. This extra burn eliminates most of the fuel savings of not needing to carry the CEV capsule to Lunar orbit and back.
And say that you save whatever lander vehicle as it is reuseable? The tanker needed to carry all this fuel, which will have to be launched by Ares-V class rockes by the way, will not be reused.
So long as all the fuel to get to & from the Moon is imported from Earth, reuseability makes no sense.
I am against this notion of Lagrange space stations too, why would you want one? Everything interesting is on the Moon, Oxygen for fuel is on the Moon, and minerals you want to mine are on the Moon. You can build telescopes on the Moon that will be better than the ones at Lagrange (superior IR and radio shielding from the Sun and Earth) too. Again, building and working in zero gravity is nearly impossible and may never be practical versus building it on the ground and launching it, on either world.
[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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#64 2006-08-18 17:28:43
- GCNRevenger
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Re: CEV is Bullshi...
I have no problems with the crew riding Ares V.
Then you don't know any better
What happend to Challenger could happen the Ares-V, this will always be a risk, a weak spot, something that can't really be worked around. Also, the RS-68 was never intended to carry people, rather it designed to be just one thing: cheap. Making it safe enough to carry people, at least in clusters like that, would not be easy.
[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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#65 2006-08-19 00:24:34
- Martin_Tristar
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Re: CEV is Bullshi...
GCNRevenger,
We are trying to go into space on a permanent basis and build a moonbase and voyage to mars. We can't do it by throwing money and resources away. If we take the apollo program they used 7 Saturn V vehicles and use and throw-away 7 second stage modules, If we want to do 25 lunar missions to establish an outpost on the moon the mass misuse of resources would increase.
The use of earth - moon return vehicle about the size of a second stage module and then refuel this vehicle for a storage facility at the ISS would reduce the overall costs to the mission to the moon. At the same time use the ISS as our luanch platform for interplanetary missions and lunar missions. The public would see the benefit for the space station and would continue the support into the space program and may even expand it towards the mars. The development of new engines and the testing of this engines could be used in the lunar missions as well.
Overall GCNR, you don't understand the management of resource allocation, public support for the space program and the increasing demands on the space vehicle platform over the next decades to come.
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#66 2006-08-19 00:55:59
- Rxke
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Re: CEV is Bullshi...
For starters, ISS is in a wrong orbit, sigh, how many more times does this need to be pointed out?
Overall GCNR, you don't understand the management of resource allocation, public support for the space program and the increasing demands on the space vehicle platform over the next decades to come.
Overall, Tristar, you don't understand basic orbital mechanics...
(You guessed right: I'm grumpy when fresh out of bed... 
)
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#67 2006-08-19 01:17:47
- Martin_Tristar
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Re: CEV is Bullshi...
Rxke,
Firstly, If a business spent 250 Billion plus dollars on a space station it would bring a return either via experiments and new technological developments or being a stepping stone for lunar missions.
If that is true and can't be used for lunar and martian missions, even if we have counted on the additional fuel requirements for moving the reusable vehicle into the correct orbital path for the lunar mission. Then it shows that the Americans and the ISS Partners didn't think ahead for space expansion, thus would be the most expensive supplier of space colonization resources ( both physically and personnel ) . That means they would most likely fail in the goal of permanent human outposts in space.
ON a personal Note - Rxke
I don't care, your opinion on my understanding or not of orbital mechanics because it would be people like me ( enterprenuers and CEOs ) that pay for people like you to do your job in space industry ( if you work in it ) and we are also the people that demand results for resources provided or you would be fired .
8)
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#68 2006-08-19 01:39:56
- Rxke
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Re: CEV is Bullshi...
(Friendly ribbing)
That's okay, I wouldn't work for a boss that wanted to use the ISS as a staging ground for lunar missions to begin with. the company would go bust that way.
Put up a Bigelow in equatorial orbit and we're talking, heehee.
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#69 2006-08-19 08:06:18
- GCNRevenger
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Re: CEV is Bullshi...
We are trying to go into space on a permanent basis and build a moonbase and voyage to mars. We can't do it by throwing money and resources away. If we take the apollo program they used 7 Saturn V vehicles and use and throw-away 7 second stage modules, If we want to do 25 lunar missions to establish an outpost on the moon the mass misuse of resources would increase.
The use of earth - moon return vehicle about the size of a second stage module and then refuel this vehicle for a storage facility at the ISS would reduce the overall costs to the mission to the moon. At the same time use the ISS as our luanch platform for interplanetary missions and lunar missions. The public would see the benefit for the space station and would continue the support into the space program and may even expand it towards the mars. The development of new engines and the testing of this engines could be used in the lunar missions as well.
Overall GCNR, you don't understand the management of resource allocation, public support for the space program and the increasing demands on the space vehicle platform over the next decades to come.
...and not one word of the huge problem I cited.
Let me spell it out for you: it will cost just as much to launch the fuel from the Earth as it would to just throw vehicles away. A reuseable vehicle will require similar amounts of fuel as an expendable one, and in order to lift this fuel from Earth to the vehicle, you will need a tanker vehicle. An expendable one! Infact this vehicle will be more complicated than the non-reuseable Lunar vehicles.
And why do you want a space station? If you have a reuseable vehicle you should want to station it someplace where its easy to work on, has the most utility, and idealy close to a non-Earth supply of fuel, right? There is such a place: the Lunar surface. Gravity and solid ground to make work easier, suborbital hops to maximize exploration-per-dollar of a base, and a relatively ready supply of Oxygen. Launch a CEV capsule and a small booster stage or else a single "big CEV," fly to Lunar orbit, and ride this lander down/up. Fuel it with Lunar Oxygen and imported Hydrogen.
Not at a space station! The ISS imparticularly is in the wrong orbit, is the wrong shape to be a orbital dock (rotational torque), and simply won't last until the "long term" can begin.
[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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#70 2006-08-20 00:28:42
- Martin_Tristar
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Re: CEV is Bullshi...
GCNRevenger,
Sometimes I find that you don't understand about the concept of reusability - the doctrine should be used from the Launch to splashdown for humans and cargo to and from earth.
To limit the waste of modules in space we design the launch vehicle on a return via parachutes to earth when expended its fuel within the atomsphere. The second stage designed on the doctrine of reuseability can be stripped down for material use in orbit or components returned to earth including the engine assemblies. Again reducing the overall cost per launch and gaining experience developing in space.
Using the Ares V main vehicle ( without booster ) could convert it into an Ares 3 Cargo and Crew Launch Platform. This would allow the creation of orbital logistic systems to remote transfer of fuel and supplies to space stations and other platforms in orbit within the use of humans. Then returning the payload vessels back to earth to be reused under the reuseablility doctrine. ( example payload vessel used 25 missions would reduce the costs by 24 spacecrafts. The use of hydrogen and oxygen propellant also in large quantities are reused when the earth's gravity draws the spent particles back to earth and the propellant is environmentally responsible.
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#71 2006-08-20 10:53:59
- GCNRevenger
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Re: CEV is Bullshi...
Doctern shmoctern, the devil is in the details as the saying goes, and goes doubly for space vehicles. All your plan accomplishes is to trade one expendable vehicle for another, while simultainiously wasting effort on reuseability.
Making a reuseable upper stage is difficult an unessesarry, already the cost of the upper stage is relatively small compared to the rest of the vehicle, and somehow making it reuseable won't save much money. For what? An RL-10 rocket engine only costs a few million and much of the rest is cheap metal that is too thin and unshielded for space use. Getting a big low-density hydrogen tank back down through the atmosphere would be very hard too, the big Shuttle tank is already at ~90% of orbital velocity and the whole thing burns up, aluminum and all. The cost of recovering and refurbishing something like that will surely wipe out the savings.
But more then that, you continue to spout dogma about reuseability without critically examining the imlications of your unshakeable faith; that say you do manage to salvage the upper stage in orbit, then what? You don't have any fuel to put in it! Its worthless, you'd have to launch another to bring up fuel for it, and then you'd have another empty vehicle with nothing to power it! No true RLV, no reuseability. Simple.
"Then returning the payload vessels back to earth to be reused under the reuseablility doctrine" If you think that you could return the Shuttle-derived Ares-V core and upper stage back to Earth for reuse, you are out of your mind.
Again, the lesson is simple... build a true space shuttle, DC-X, something like that or don't bother with reuseability.
[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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#72 2006-08-20 21:32:09
- RedStreak
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Re: CEV is Bullshi...
Doctern shmoctern, the devil is in the details as the saying goes, and goes doubly for space vehicles. All your plan accomplishes is to trade one expendable vehicle for another, while simultainiously wasting effort on reuseability.
That is indeed the trick.
Remember, the space shuttle was the 1970s poster child of spacecraft reuseability. Instead of lowering the cost and increasing launch rates it did the exact opposite and everything ultimately blew up in everyone's face with both Challenger and Columbia.
While the launch pad waits for a single shuttle for four, even five months easily a dozen various expendable vehicles are launched...and with less cost since there is no worries on recovering, no parachutes, no refurnishing. Think about the effort you put into ceramic plates: you prepare a sink of soapy warm water, you put in it, scrub it, wipe, and put it into a dishwasher. Effort of the disposeable paper plate: open garbage can insert. That is the harsh trouble with reuseability.
Its not impossible but like every man every spacecraft needs to know its limits.
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#73 2006-08-20 21:43:22
- RedStreak
- Banned
- From: Illinois
- Registered: 2006-05-12
- Posts: 541
Re: CEV is Bullshi...
To limit the waste of modules in space we design the launch vehicle on a return via parachutes to earth when expended its fuel...
This would allow the creation of orbital logistic systems to remote transfer of fuel and supplies to space stations and other platforms in orbit within the use of humans. Then returning the payload vessels back to earth to be reused under the reuseablility doctrine. ( example payload vessel used 25 missions would reduce the costs by 24 spacecrafts. The use of hydrogen and oxygen propellant also in large quantities are reused when the earth's gravity draws the spent particles back to earth and the propellant is environmentally responsible.
So you plan on using the Earth's gravity to supply propellants? :?
Look...you're advocating saving fuel, right? Why not consider, for long space voyages, storing fuel and propellant in one wonderful package: it's called H2O. If you want one of these giant vessels lugging H2 and O2 across space considering doing it at non-cryogenic temps.
Aside from that, refer to what GNC and I wrote on reuseability. We're not saying its a crock but we're keeping it real.
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#74 2006-08-20 22:32:18
- Martin_Tristar
- Member
- From: Earth, Region : Australia
- Registered: 2004-12-07
- Posts: 305
Re: CEV is Bullshi...
Redstreak,
I am not going to explain the environmental benefits of the use in hydrogen / oxygen based launch environment.
GCNRevenger,
The Ares 1 Re-entry Capsule will be a reuseable capsule from the specs outlined in the NASA Documents. By Designed variations for the Ares V to have similar features would add the expansion of space. But, if they have decided to go for one use vehicle then , it shows the misuse of government funding again. I never said I liked the space shuttle because it slowed the development of space from the Saturn V rocket platform - we could have expanded the Skylab with more modules, solar panels, more and possible even an outpost on the moon but the officials decided to go with the shuttle over the rocket and therefore limited the lift capacity until now with the ares v coming back.
Now its time to expand the development of space with newer designed for the payload to carry personnel and cargo into orbit and beyond. All issues have solutions and we could develop a long term crew vehicle for ferrying personnel to orbit their to a space station / factory or another space vessel. I find that you want to throw things away all the time and yet don't want to move forward in creating a space industry that can accomplish the ideals of many of the mars society members and other space society members are working towards, which is Human Settlement in space NOT joyrides, NOT tourist missions, BUT permanent settlements and outposts.
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#75 2006-08-20 22:43:12
- RedStreak
- Banned
- From: Illinois
- Registered: 2006-05-12
- Posts: 541
Re: CEV is Bullshi...
Actually Martin_Tristar I have an idea what you mean. H2 and O2 make water, which is perfectly natural versuses fuels like keroseone, methane, and certainly hypergolics. That was an idea behind the X-33 (as a bad example I'll admit). And I also note how garbage is piling up on the ocean bottom courtesey of spent rocket shells and even LEO debris too. Eventually a completely reuseable booster that is purely H2O in terms of waste will arrive...but given all the priorities space flight has to face and the larger concern of a few million cars around the world...
...well the sheer math explains itself. However your point is valid all the same.
Regarding government funding government is gonverment for better or worse. :? It was tough enough to get the VSE accepted as is.
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