Please forgive if this has already been discussed (it surely has somewhere), but I couldn't find a dedicated thread.Assuming Ares I/Orion flies but Ares V development cannot be funded, could Ares I and existing or nearly-existing EELVs be used to perform a lunar landing mission? I notice that an Ares I upper stage would be large enough to serve as a formidable Earth Departure Stage if it could be orbited and refueled in orbit over time (with a still-to-be-developed restartable J-2X). An Ares I could orbit its own upper stage, retaining roughly 20 tonnes of propellant, presumably topped by a refueling module with some type of power supply, etc. Multiple refueling missions (perhaps as many as four or five) could be conducted by EELVs, or other types of launch vehicles. These would dock or berth somehow to the refueling module atop the upper stage. Some development (an add-on module?) would be necessary to handle the autodocking. Ares I or an EELV could be used to orbit a partially fueled Altair, which would be fully refueled by another launch. Finally, an Ares I would boost an Orion with crew to dock to the upper stage/Altair stack, which would then be boosted toward the Moon by the upper stage.An interesting feature of this design is that an Ares I upper stage can carry more propellant than the Ares V EDS is planned to hold in orbit. This means that TLI payload masses can be tailored to the mission and can, if needed, exceed the planned 1.5 architecture numbers.A lot of launches though. Eight perhaps, or fewer if more powerful EELV variants can fly. I would expect such an architecture to be able to support only one lunar landing per year. - Ed Kyle
If Ares V is cancelled there is even less reason to maintain Ares I. Atlas or Delta can launch as much weight into orbit using a small ground force. An EELV moon program would be a challenge to run but doable. By I don't see any advantage to using Ares I in any of this.
One challenge in this architecture would be fitting a lander into an EELV fairing, even if you used a hammerhead on a Delta IV
A denser, heavier propellant would result in a smaller Altair.
You must also develop Propellant Depot capabilities before you will ever be able to go to the moon. Both low-boiloff orbital storage and Propellant Transfer technology are low-TRL problems -- and low-TRL problems typically result in costly and time-consuming development work -- so this approach isn't going to be a cheap one.Ross.
How bout this, typical lunar module type lander with dense propellants, but with a fluffy LOX/Hydrogen crasher stage taking care of most of the deltaV. A two stage descent. Smaller lander sits atop longer cylindrical crasher stage in the payload fairing.edit: Or have the ascent module separate and do the proximity landing after the descent module behaves in the manner above.
Quote from: Will on 11/17/2008 05:54 pmOne challenge in this architecture would be fitting a lander into an EELV fairing, even if you used a hammerhead on a Delta IVThe 5.5 meter diameter Ares I upper stage is wider than the 5 meter Delta IV, but an Altair would still require a 2 meter diameter increase over Ares I. Perhaps, since a fully fueled Ares I upper stage on orbit would be able to boost as much as 100 tonnes toward the moon, NASA would be able to rethink the Altair descent stage propellant. A denser, heavier propellant would result in a smaller Altair. - Ed Kyle
This might be enough for a smaller EDS that can send the lander to the moon using a Hohmann transfer vs the typical transfer.
Quote from: edkyle99 on 11/17/2008 07:22 pmQuote from: Will on 11/17/2008 05:54 pmOne challenge in this architecture would be fitting a lander into an EELV fairing, even if you used a hammerhead on a Delta IVThe 5.5 meter diameter Ares I upper stage is wider than the 5 meter Delta IV, but an Altair would still require a 2 meter diameter increase over Ares I. Perhaps, since a fully fueled Ares I upper stage on orbit would be able to boost as much as 100 tonnes toward the moon, NASA would be able to rethink the Altair descent stage propellant. A denser, heavier propellant would result in a smaller Altair. - Ed KyleAn Altair fairing atop an Ares I upper stage atop a 5 segment SRB? The mind reels.
Quote from: libs0n on 11/17/2008 08:38 pmHow bout this, typical lunar module type lander with dense propellants, but with a fluffy LOX/Hydrogen crasher stage taking care of most of the deltaV. A two stage descent. Smaller lander sits atop longer cylindrical crasher stage in the payload fairing.edit: Or have the ascent module separate and do the proximity landing after the descent module behaves in the manner above.Another alternative might be to separate the lunar orbit insertion function from the descent stage. All of these ideas require more engines, except for ascent module landing idea.Using hypergolics for the LOI and descent rather than hydrogen/LOX would require the addition of perhaps 25 tonnes to the TLI mass. That's not possible with Ares V, but it is possible with an EOR mission using a TLI stage based on the Ares I upper stage. It would mean adding one or two extra propellant transfer flights, however. A hypergolic Altair would be smaller than the current design, but it would still be pretty big. - Ed Kyle
Quote from: Will on 11/17/2008 08:48 pmAn Altair fairing atop an Ares I upper stage atop a 5 segment SRB? The mind reels.The could name it the Good Ship Lollipop...
An Altair fairing atop an Ares I upper stage atop a 5 segment SRB? The mind reels.
Quote from: William Barton on 11/17/2008 08:59 pmQuote from: Will on 11/17/2008 08:48 pmAn Altair fairing atop an Ares I upper stage atop a 5 segment SRB? The mind reels.The could name it the Good Ship Lollipop...A fairing large enough to house an Altair (which is 7.5 meters in diameter) would be "skinnier", relative to the launch vehicle diameter, than the Titan IV fairing was relative to its core vehicle diameter. It would be a little bit "fatter" than the Ariane 4 and Atlas III fairings relative to their vehicle diameters. - Ed Kyle
1. It might be easier to convert a Falcon 9 upper stage into an EDS vs trying to refuel an Ares I US and just live with the lower performance 2. since it's not cryogenic and already has three axis RCS with basic translational control.
My assumption in posting this "what if" is that Ares I and Orion development continues and is completed, but that money can't be allotted to develop Ares V.
Could an EELV based human launch system be developed? Sure, but it is not funded, is not currently underway, and is not the intended topic of this thread.
However, once you answer the hypothetical "can you reach the Moon using Ares I and EELV?" the next obvious question is "but why would you?" I don't know if you can avoid that topic.
{snip}I wonder if there aren't other propellants we could consider for the Altair(or any other aspect like an Orion tank redesign). One that I have in mind due to its occasional mention as a possible LV propellant is the hydrogen peroxide/kerosene combination. It seems to me to strike a good balance: it's dense, it's non-cryogenic, and I'm under the impression it has better specific impulse than hypergols, nearly LOX/kerosene levels. Of course, I've never seen it suggested as an in space fuel, so it may have problems I'm not aware of. Plus it would be new ground.
Quote from: libs0n on 11/18/2008 12:09 am{snip}I wonder if there aren't other propellants we could consider for the Altair(or any other aspect like an Orion tank redesign). One that I have in mind due to its occasional mention as a possible LV propellant is the hydrogen peroxide/kerosene combination. It seems to me to strike a good balance: it's dense, it's non-cryogenic, and I'm under the impression it has better specific impulse than hypergols, nearly LOX/kerosene levels. Of course, I've never seen it suggested as an in space fuel, so it may have problems I'm not aware of. Plus it would be new ground.The problem with H2O2 is the freezing temperature. You would need a ton of heaters to keep it storable. So that would be a NO, not possible, even with 'possible' additives. Same goes for Kerosene: great fuel, but it would freeze in space, or at the very least gel. That's why MMH & hydrogen are preferable fuels in space. Methane is an option, but of the top of my head (since dial-up can't help me in searches right now) I think it is desireable as an ascent fuel rather than descent. Don't hold me to that, it might be possible.
{snip}The problem with people in space is their freezing temperature. You would need a ton of heaters to keep them alive ... so no, people is space is not possible ... (Hope you don't mind ... I couldn't resist.) In case there is any doubt ... I disagree. The problem we have with cryogenic loitering is heat and boil off issues ... not cold. Skylab lost some shielding / insulation and the internal temperatures skyrocketed. Just my three cent guesstimate ... its been 25 years since I had heat transfer ... I haven't even tried to do the math.
Quote from: imcub on 11/18/2008 01:36 am{snip}The problem with people in space is their freezing temperature. You would need a ton of heaters to keep them alive ... so no, people is space is not possible ... (Hope you don't mind ... I couldn't resist.) In case there is any doubt ... I disagree. The problem we have with cryogenic loitering is heat and boil off issues ... not cold. Skylab lost some shielding / insulation and the internal temperatures skyrocketed. Just my three cent guesstimate ... its been 25 years since I had heat transfer ... I haven't even tried to do the math.Heck I don't mind, but heat is still an issue. From a Canadian's perspective: you can always add, layers, but there comes a point when you can't take any more off Boil-off if an issue from a cryo fluids stand-point, but if a fluid freezes in the lines (or worse the tanks), nothing is going to work. Tanks rupture if the fluid expands during freezing (I had to explain it that way since some fluids contract).There are some hypergols which would work nicely, but they are not that pleasant, have a habit of eating away stainless & CRES, and fairly toxic. We tend to avoid those for simplicity. MMH is by far one of the better ones for long term storage, though we accept the hazard.
Quote from: Patchouli on 11/17/2008 08:45 pm1. It might be easier to convert a Falcon 9 upper stage into an EDS vs trying to refuel an Ares I US and just live with the lower performance 2. since it's not cryogenic and already has three axis RCS with basic translational control.1. No it wouldn't. Also Falcon 9 not the end all LV, it is a paper rocket from these discussions point of view. It has lesser performance and it is not proven. No matter how bad Ares I is, it is more real than Falcon 9 from NASA's point of view.2. No, it uses LOX, therefore it is cryogenic
Quote from: libs0n on 11/17/2008 08:38 pmHow bout this, typical lunar module type lander with dense propellants, but with a fluffy LOX/Hydrogen crasher stage taking care of most of the deltaV. A two stage descent. Smaller lander sits atop longer cylindrical crasher stage in the payload fairing.edit: Or have the ascent module separate and do the proximity landing after the descent module behaves in the manner above.Another alternative might be to separate the lunar orbit insertion function from the descent stage. All of these ideas require more engines, except for ascent module landing idea.
Storing LOX is going to be a lot easier then hydrogen.Liquid O2 -182.96 °C liquid H2 -252.87 CAll LOX is going to need to stay cool enough is a sun shade and maybe a radiator while lH2 is either going to boil off or will require active refrigeration for storage in LEO.
BTW F9 is no paper rocket they are building and testing real hardware right now which is a lot more then I can say about Ares I so stop trolling.
Which brings up an interesting point for space skeptics ... if we aren't willing to go to the moon using the Ares I and EELV route ... then it must not really be worth going to ... so why should US taxpayers foot the bill for any moon program?
Personally, if Ares I and EELV was the only option, I would want take it ... and then hope the bigger Mars launcher would be funded when it was time to go to Mars.
[Sidebar: I can see parallels that could be applied to the Direct argument. Build Direct, use it for the ISS and Lunar missions ... then build the Mars Rocket when you need it for Mars missions, not Lunar ones. /Sidebar]
Well, it appears (if we use Ross' numbers) that an all EELV moon program will cost more, in total, than an alternative 2-launch achitecture based on similar vehicles. Also, the additional number of launches per lunar flight greatly increases the risks of LOM, possibly to the point of making it financially untenable and probably to the point of outweighing any EELV advantages even if Ross' numbers are wrong.So the question becomes can you show that an all EELV program is actually less expensive than a 2-launch architecture. This includes both development & operations. In either case, the cost will be very high.
Dude, what's the point of this? Why develop something with 0-25% more performance when the existing item is 14% to 40% the cost per mass? A better solution would be EELV/EELV architecture. Better for the taxpayers and future space travelers, worse for Alabama (north of the river) and Utah.
The benefit of using an Ares I is that it provides an already-developed upper stage that could be modified to perform the TLI role. EELV doesn't provide such a stage <snip>
Quote from: edkyle99 on 11/18/2008 02:25 pmThe benefit of using an Ares I is that it provides an already-developed upper stage that could be modified to perform the TLI role. EELV doesn't provide such a stage <snip>.. neither does Ares I at this point. Ares I upper stage is far from "already-developed". You're comparing EELVs of today with a would-be, future Ares I. Rather unfair, don't you think?
The basis of this discussion is the assumption that Ares I development continues to completion.
Space tug.Tanker vehicles.
Another benefit of using both Ares I and EELVs is that no modification of existing EELV designs, and no U.S. production of RD-180, would be required. (Griffin has said that Atlas V was the preferred EELV for Orion if EELV would have been the choice.) Since EELV would not fly Orion in this architecture, any model of either EELV (or any other available launch vehicle for that matter) could be used to fly up the propellant, etc.. - Ed Kyle
I'd prefer to launch the CEV on a Delta IV heavy and invest the money in U.S. production of the RD-180 (lets face it, it is an amazing engine in terms of T/W, ISP, thrust).Replace the stick with the Delta IV heavy and replace the SRBs on an Ares V with RD-180 derived strap on boosters (you have what, 8-10 years to create such strap ons).In the end, Boeing and LockMart are happy, CEV flies to ISS, Boeing gets a RS-68 regen out of Ares V and LockMart gets a U.S. RD-180 out of Ares V.None of this will happen of course
Reminds me of the movie Patton ... Don't for get the Russians ... er ... Don't forget ATK ...
Ares I will probably cost more than EELV, but EELVs aren't as cheap as everyone seems to believe. The benefit of using an Ares I is that it provides an already-developed upper stage that could be modified to perform the TLI role. EELV doesn't provide such a stage, so it would have to be developed for an EELV/EELV approach.
Quote from: edkyle99 on 11/18/2008 02:25 pmAres I will probably cost more than EELV, but EELVs aren't as cheap as everyone seems to believe. The benefit of using an Ares I is that it provides an already-developed upper stage that could be modified to perform the TLI role. EELV doesn't provide such a stage, so it would have to be developed for an EELV/EELV approach.Some of us know how much EELVs cost, though the exact numbers are proprietary."Already-Developed Upper Stage" Sir, you are seriously misinformed. EDS will be a whole new stage.I've never advocated crewed EELV to anywhere past LEO. But Ares I should NEVER fly because EELV is in the same class and is FAR cheaper. I'd rather have the Atlas and Delta guys designing an Ares V class rocket, but I realize that may be politically untenable.
As for EELV cost, all one has to do is look up how much the government spent on the EELV program this year (at least $1.2 billion and probably hundreds of millions more) and divide by the number of launches (two so far).
Since we're comparing architecture here... there's a scenario I've been wondering about: Say the currently planned "1.5 launch" scheme actually comes to fruition (which I doubt, but play along)...There is a lunar outpost with an "expedition" crew two months into their 6 month stay. There is a problem with the Orion in Lunar orbit (ala Apollo 13, Skylab 3, whatever) and it becomes unusable. Of course, the crew at the base are in no immediate danger. So the question becomes:How to launch just a rescue Orion to lunar orbit to replace the dead one?1). Can Ares 1 launch Orion to the moon? Since it would be unmanned, could it use a direct ascent without LEO? Yes, such a path might be one big black zone, but, again, it would be unmanned, and would not even need the LAS (saving weight). Is this do-able?
If Not...2) Would NASA dummy up some adapter on Ares V to lift an Orion / EDS to LEO to perform a TLI.
Then...3) Once headed to the moon, can Orion by itself (with NO Altair) have the propellant to do both a LOI and then the TEI? (since right now, Altair does the LOI).
4) OR... Would they launch the normally scheduled next mission hardware, (1.5 launch Orion + Altair), say, with one astronaut (remember, Orion would have to dock with EDS/Altair). When that arrives in LLO as normal, Altair is jettisoned (sacrificed), and the outpost crew launches to meet the lone member on the new Orion for return. Seems a real waste of an Altair.
5) Is there some other alternative? With EELV's?
Seems like it would be a big public relations fiasco if NASA had to say it couldn't get a rescue Orion to Lunar orbit given a period of months to save the lunar base crew.
Which is why NASA needs to start banging the drum now that exploration is risky and that casualties, though to be avoided if possible, are inevitable. If casualties cannot be tolerated, then we have no business even attempting this at all.
Quote from: edkyle99 on 11/21/2008 09:55 pmAs for EELV cost, all one has to do is look up how much the government spent on the EELV program this year (at least $1.2 billion and probably hundreds of millions more) and divide by the number of launches (two so far). So wouldn't it make sense to increase the number of launches (via NASA LEO ops) to decrease the cost to all while investing in the improvement of an operating fleet of LVs? Win-win?
Quote from: edkyle99 on 11/18/2008 07:05 pmAnother benefit of using both Ares I and EELVs is that no modification of existing EELV designs, and no U.S. production of RD-180, would be required. (Griffin has said that Atlas V was the preferred EELV for Orion if EELV would have been the choice.) Since EELV would not fly Orion in this architecture, any model of either EELV (or any other available launch vehicle for that matter) could be used to fly up the propellant, etc.. - Ed KyleI'd prefer to launch the CEV on a Delta IV heavy and invest the money in U.S. production of the RD-180 (lets face it, it is an amazing engine in terms of T/W, ISP, thrust).Replace the stick with the Delta IV heavy and replace the SRBs on an Ares V with RD-180 derived strap on boosters (you have what, 8-10 years to create such strap ons).In the end, Boeing and LockMart are happy, CEV flies to ISS, Boeing gets a RS-68 regen out of Ares V and LockMart gets a U.S. RD-180 out of Ares V.None of this will happen of course
Quote from: EE Scott on 11/21/2008 10:26 pmQuote from: edkyle99 on 11/21/2008 09:55 pmAs for EELV cost, all one has to do is look up how much the government spent on the EELV program this year (at least $1.2 billion and probably hundreds of millions more) and divide by the number of launches (two so far). So wouldn't it make sense to increase the number of launches (via NASA LEO ops) to decrease the cost to all while investing in the improvement of an operating fleet of LVs? Win-win?An Ares I/EELV architecture would do just that, requiring perhaps four or more EELV launches for each lunar mission. NASA would get an Ares infrastructure. The Air Force would get more flights out of EELV. The U.S. would get maximum use out of all of these vehicles, with salvo launches from all of the Florida pads. Win. Win. Win? - Ed Kyle
Quote from: Jorge on 11/22/2008 05:40 pmWhich is why NASA needs to start banging the drum now that exploration is risky and that casualties, though to be avoided if possible, are inevitable. If casualties cannot be tolerated, then we have no business even attempting this at all.The public will tolerate casualties in manned spaceflight; if anything, Challenger & Columbia have shown that to be the case, even though they shouldn't have been tolerated, since there were ample warning signs that both could have been prevented if it were not for arrogance and overconfidence. However, if a 1.5 launch architecture can't send a LON rescue Orion to LLO given a time frame of months, it will be viewed by the public as flawed and not thought out.
Some unforseen mechanical failure or MMOD causing LOC will be tolerated. But lack of reasonable contingency planning will not be.
If you can't do it right (i.e., with reasonable contingency as viewed by the public)... then don't do it.
"Too risk averse to deserve a space program."That's where my brain is heading. Congressmen and the media who dictate national sentiment get their guts in a knot that we are all partially responsible when astronauts die. My answer: fund development of capabilities in the private sector. Then it's the companies putting their test pilots or customers on the line. It's (slightly) easier to stave off regulation than to perpetuate funding.
LON rescue wasn't possible for Apollo and it won't be economically feasible for CxP, regardless of architecture.
I am *not* talking about EDS. I am talking about an architecture that lets NASA *skip* development of EDS. I'm taking about an architecture that allows the first launch to place an Ares I upper stage - a *modified* upper stage that could be developed much more rapidly than EDS and Ares V - into low earth orbit. This stage would serve first as a propellant depot and second as a lunar transfer injection stage.
It was available with Skylab (sort of), and for shuttle (after Columbia). There's no reason that with proper planning it shouldn't be expected with CxP. Anything less is negligence.
I wonder how feasible it is to have a lunar escape module, fully fueled, ready to go as a LON from the lunar surface? I mean, considering all the technical & logistical issues, wouldn't it make sense to develop a LAS specifically for RTE capability? Of course I don't mean a vehicle loitering in lunar orbit either. One shot, spacesuits only, emergency vehicle.It's one thing to have an EELV or other vehicle available to launch such a mission (since there is the chance it would launch un-manned). But for medical or other needs (solar issue), having that capability at hand, rather than waiting for it, seems more logical?Please, spare me the cost figures. We've been up and down that so many times. What really counts is the public's perception here. It's much cheaper to have a 'well done, good thinking' applause with "how much did that cost anyway?" later, than to lose a crew.
Now we're in luck here as there is a vehicle under development right now that could be used in the same manner as Gemini.
For the outpost, the solution is fairly straight-forward. You add one extra LSAM into the cycle, so there are always two available. If one fails to lift, the crew switches over.For sortie missions its far more complicated.I wonder what would be required to deliver 2-months of oxygen, food and water in a usable package which could be launched on almost any rocket? If we had a dozen "emergency survival packs" sitting in a warehouse at KSC and had all the procedures drawn-up and ready to go at a moment's notice for Atlas, Delta-II and Delta-IV (and Jupiter), ready to fly on an extremely expedited consciously high-risk launch attempt, we could potentially deliver minimal survival equipment to a stranded crew to help them survive until we can get a proper rescue mounted. The stranded crew would need at least a week's worth of resources on the surface at the time of 'the call', but that ought not to be too much mass penalty for Sortie missions to include.I think a study into such a capability would be a really good idea.Ross.
For the outpost, the solution is fairly straight-forward. You add one extra LSAM into the cycle, so there are always two available. If one fails to lift, the crew switches over.For sortie missions its far more complicated.Ross.
For the outpost, the solution is fairly straight-forward. You add one extra LSAM into the cycle, so there are always two available. If one fails to lift, the crew switches over.For sortie missions its far more complicated.I wonder what would be required to deliver 2-months of oxygen, food and water in a usable package which could be launched on almost any rocket?
Quote from: Patchouli on 11/18/2008 03:30 amStoring LOX is going to be a lot easier then hydrogen.Liquid O2 -182.96 °C liquid H2 -252.87 CAll LOX is going to need to stay cool enough is a sun shade and maybe a radiator while lH2 is either going to boil off or will require active refrigeration for storage in LEO.And how exactly would you keep such a mixture homogenous?? Let alone the different properties of the two... Sounds like it would create more problems that it would solve... JMHO! OL JR Dude, use K for cryogenic stuff- it's easier to deal with.As for cryogenic fuels, is it possible to mix methane and hydrogen to get a stable liquid phase that boils in the ~80K range? It might be one way to ease handling without adding too much fuel mass. Of course, you'd need a new engine...
The problem is that the Ares I US would absolutely suck as the starting point for an EDS or for a propellant depot. It's not even restartable! The only thing the Ares-I upper stage has going for it is it's propellant volume. AIUI, here are a few specific issues:1. The isogrid structure sucks for long-duration cryo storage. Think lots of tiny heat exchangers.2. The structure is designed to take crazy amounts of accelerations and max dynamic pressures, meaning it has to take much heavier loading than an in space stage, and is thus not as structurally efficient.3. Not designed for restartability.4. External foam insulation (which is pretty much needed to make Ares-I US work) is just about useless in vacuum compared to better forms of insulation.5. The stage T/W ratio is higher than it needs to be, which means that you've got a heavier engine than you really want for in-space use.I think the ACES stage ULA has been working on is a much better starting point for a refuelable EDS or depot. It's extendable up to sizes similar to the Ares-I US, but is designed from the start in a way that makes it a lot more friendly to long-term cryo storage. Adding refueling hookups to an ACES stage would be possible, and they've already looked into the concept of "mission specific kits" for different applications (long duration storability, lunar ops, etc).~Jon
[...]As for thrust to weight ratio, a reloaded Ares I upper stage would weigh about the same as an Ares V EDS at TLI ignition, and of course it would be powered by the same engine and therefore have the same T/W ratio. - Ed Kyle
Quote from: edkyle99 on 11/26/2008 06:42 pm[...]As for thrust to weight ratio, a reloaded Ares I upper stage would weigh about the same as an Ares V EDS at TLI ignition, and of course it would be powered by the same engine and therefore have the same T/W ratio. - Ed KyleStill, it can't restart.