More unsubstantiated ad hominem that do not correspond to my personal experiences with him.
We believe that due to its heritage to flying systems, that the Jupiter will fundamentally be at one end of that particular spectrum and that Ares-I will be at quite the other.BTW, some of our engineers have already produced some low- to medium-fidelity Pro-E models of the Jupiter vehicles which they have been using for FEM work in aerodynamic and load analysis. Exactly what & how, I don't personally know the details -- they've just told me that's what they've been doing. I would hope that if we are ultimately selected, those models would quickly begin to 'do the rounds' so that all the other departments can start gathering some initial data just to get the ball rolling for the Pre-DAC, while higher-def versions are created. Hopefully that will help to give everyone a step-up on the long road whenever the time comes.Ross.
The happens, incidentally, with Jupiter 232 as well, if built. Both are going to be very difficult for a commercial launcher to compete with on a commercial launcher price determined by average cost plus profit.
Likewise, if NASA is using EELVs in large numbers to fill a depot, DOD is going to want NASA to pick up an appropriate share of their fixed costs.
The big problem with the SSME is that it is expensive to just toss it away after each mission. Is there any way to recover the SSME? Jupiter has all of that extra lifting capability, couldn't some type of recovery system be developed? I'm thinking along the lines of having the SSMES attached to a pod on the bottom of Jupiter that would then be jettisoned from the core.
it can be scary how we even got this far...
Without going into details, could you find out what parts they are making with pro-e and which parts they are using legacy FEM's for?
And if they are using an in-house code for loads analysis?
It's selfish, but if I know that your analysis was done well, that inspires confidence that there are no showstoppers in developing Jupiter.
Quote from: gladiator1332 on 01/19/2009 05:39 pmThe big problem with the SSME is that it is expensive to just toss it away after each mission. Is there any way to recover the SSME? Jupiter has all of that extra lifting capability, couldn't some type of recovery system be developed? I'm thinking along the lines of having the SSMES attached to a pod on the bottom of Jupiter that would then be jettisoned from the core. I'm no expert is such things, but I think the major problem with this is not designing a rocket mount that could jettison so the rocket motors could be recovered, but is that by the time you'd jettison it, you are in LEO going 17,500 MPH. With the shuttle, the SRB's jettison really at about suborbital level, then the SSME's continue to burn with the ET to get the Shuttle to orbital velosity. So a detatchable SSME pod at the bottom of the new ET would just burn up upon rentry. Trying to equip it with some sort of heat shield would obviously be impractical. With the Shuttle, you knew you could retreave the engines so you could make a more complex, high-tech engine that was expensive.The only practical I could see to do that is to go with liquid boosters that could be throttled with expendable rocket motors, and basically the core would be burning 100% to get suborbital, with the boosters throttled back to conserve fuel, then a SSME pod could be jettisoned, and the boosters turned up for orbital insertion. But now you can't recover your boosters as they'd burn up on reentry, so you are back to square one.Maybe that would be a little cheaper, but likely it'd be more like a wash, with the added complexity of jettisonable engines on the core.
Hi Lobo, Those diagrams were actually produced back around the v1.0 > v2.0 switch around in early 2007 IIRC. They're not as up-to-date as they ought to be (I need a handful of 30 hour days!). We were very interested in the possibility of a 2-launch LOR-LOR mission around that time, but when we ran the numbers through the computer we found that in practice, the performance wasn't so hot Essentially you lose quite a lot of total performance by having to drag the mass of the second EDS thru TLI as well. You've got a fixed CEV mass, a variable LSAM which is dependent on the propellant/EDS mass in LEO and only a finite amount of propellant. The extra EDS mass depletes the total payload throw mass thru TLI and results in a smaller LSAM inserted into LLO. There were a variety of compatible propellant transfer options to make maximum use of the throw-capacity, and there were even options considered for the EDS to perform the LOI burn in some instances (for CEV, if not for the LSAM). But the total performance never quite reached the levels of the current connect-mode EOR-LOR approach and the LEO Propellant Depot arrangement blows its sock right off, so we set the LOR-LOR architecture aside. The place where that mission profile is still worth keeping in the back pocket is in case we ever develop a reusable Lander. In that future scenario, the LSAM would be launched to Lunar Orbit by a single J-232. It can then be used 'x' times before needing to be replaced. It would be refueled (probably by Lunar ISRU) and so the only hardware which must travel from Earth is the Orion and whatever science packages the crew is bringing along. Each of those missions can then also be launched on single J-232's too. Its just one of the many different paths which we could take in the future. But the LOR-LOR work which we did would apply quite well to it.Ross.
It might be possible to come up with a good upgrade in the future to allow J-232 Cores to be recovered, perhaps.
Real quick, I keep hearing the "propellent depot" term thrown around, but must have missed the orginal discussion about it. What's the Cliff's Note's version of that that is?
...there were even options considered for the EDS to perform the LOI burn in some instances (for CEV, if not for the LSAM). But the total performance never quite reached the levels of the current connect-mode EOR-LOR approach and the LEO Propellant Depot arrangement blows its sock right off, so we set the LOR-LOR architecture aside.
But this isn't a useful subject to dwell upon. He's gone. None of this matters any more. End of story. We need to get focused on the future.
Quote from: Will on 01/19/2009 08:20 pmThis happens, incidentally, with Jupiter 232 as well, if built. Both are going to be very difficult for a commercial launcher to compete with on a commercial launcher price determined by average cost plus profit.No commercial launcher will ever have to compete against either the Ares or the Jupiter. It is against the law for NASA to ever compete against any commercial launcher for any kind of commercial payload. None of the commercial launchers will ever have to concern themselves with this, no neither should we. It's just not in the mix and not worth bringing up.
This happens, incidentally, with Jupiter 232 as well, if built. Both are going to be very difficult for a commercial launcher to compete with on a commercial launcher price determined by average cost plus profit.
Real quick, I keep hearing the "propellent depot" term thrown around, but must have missed the orginal discussion about it. What's the Cliff's Note's version of that that is? A fuel tank in LEO? In Lunar Orbit?
Also, what are the difficulties in transferring fuel in space? Is it done by pressure? (in which case you could only load until the tanks were equalized, leaving a lot of propellent in the source left). Or with Turbopumps? Would that add a lot of cost/complexity to the equipment?
The reusable Lander is an interesting idea. No reason to expend that whole vehical every time you have a mission. What's the status on an ISRU method of refuelling the LSAM? A long way off?
If so, the fuel could still be brought from earth. Perhaps the EDS could be design with enough extra propellent to refuel the LSAM upon LOR?
Meaning, if you were only boosting Orion to Lunar Orbit, would you have enough extra weight capacity on a J232 for extra tanks on the EDS for the LSAM in a single J232 launch?
That'd sure be a cost saving if you can do a full Lunar Mission with 1 launch instead of two. And you'd forgo all LEO docking, and the whole uppersage of the J232 with EDS and Orion would boost right to LOR with the LSAM, fuel it, then jettison the EDS.The process could be further simplified if you could fuel the LSAM through the docking ring on Orion. Then you only need one docking maneuver on the whole trip (until returning from the surface anyway)
Ben, I need to correct a few bits there.We propose building a 'cradle' which we refer to as an SSPDM (Space Shuttle Payload Delivery Module) which would be designed to carry one of the standard Shuttle/ISS MPLM's to orbit one last time. The SSPDM may or may not have an integral RCS system -- specifically depending on Orion's capabilities. The SSPDM would be a disposable unit for carrying any remaining Shuttle Payloads one last time. Once the payload (MPLM in this case) is finished with, it would be taken away by the accompanying Orion and placed into a safe orbit where it would burn up in the atmosphere. The Orion would safely return home alone.The SSPDM is also planned to be the basis for launching a future Orion-based Hubble Servicing Mission somewhere in the 2014 time-frame too. After that mission the SSPDM would either be disposed of safely, or would be fitted with its own guidance and control systems and would be placed into an orbit compatible with Hubble, but a few hundred miles distant. There it would remain, along with all the tools needed to perform any future servicing missions, ready for an Orion crew to dock with and bring back to the telescope once again.We always liked the idea of the un-crewed Orion being an option for cargo-only deliveries and cargo down-mass capabilities. Theoretically at least, a cargo-only variant of Orion could still be produced -- although neither CxP nor DIRECT have a budget allocation for it in the plans at this time. It remains an option though.And currently our suggestion is to utilize the slightly larger Delta-IV Heavy Upper Stage for the Lunar Flyby mission in December 2013 (45th anniversary of Apollo . The reason being that the DIVHUS has a greater propellant load than the Centaur-V1 and therefore a higher total impulse for that mission. A side-effect of this choice to use the Delta hardware is that together with the human-rated RS-68's, the Jupiter would cover more than half the total costs of human-rating the Delta-IV Heavy for human use -- making it a very cost-effective option to consider.Hope that helps clarify the situation a little.Ross.
Quick question, would the J120 have enough power to boost it directly to the ISS? Or would Orion specifally have to flip, dock, and boost with it's engine?
Quote from: Lobo on 01/19/2009 11:16 pmQuick question, would the J120 have enough power to boost it directly to the ISS? Or would Orion specifally have to flip, dock, and boost with it's engine?It is not an issue of "power." The J-120 is a launch vehicle, not a spacecraft. It lacks capabilities for relative navigation, rendezvous targeting, guidance, and the precise control needed to perform rendezvous and prox ops with the station. A spacecraft/tug with the above capabilities, such as Orion is required in order to bring the SSPDM safely into proximity with the station.
Quote from: Jorge on 01/19/2009 11:26 pmQuote from: Lobo on 01/19/2009 11:16 pmQuick question, would the J120 have enough power to boost it directly to the ISS? Or would Orion specifally have to flip, dock, and boost with it's engine?It is not an issue of "power." The J-120 is a launch vehicle, not a spacecraft. It lacks capabilities for relative navigation, rendezvous targeting, guidance, and the precise control needed to perform rendezvous and prox ops with the station. A spacecraft/tug with the above capabilities, such as Orion is required in order to bring the SSPDM safely into proximity with the station.Well, what I mean is this. Just from a boosting and velosity standpoint, will the J120 give the payload enough to get it to the ISS? Or will it require extra burns to get it there?
If not, I was wondering if you could leave the whole Orion/shroud/SSPDM assembly intact as you catch up to the ISS. Orion's OMS would still be able to opereate to make course changes and slow down when it gets in ISS proximity.
Then it could dock with the ISS and the CanadaArm could open the shrud and remove the payload Similar to how the Shuttle does it. (unless you need a second manipulator arm on the SSPDM to do this).And the only reason I mention this is a curiosity of the complexity of an ISS mission to deliver a new module. Otherwise, you'd have to jettison the shrowd (or open it like Apollo did when extracting the LEM),
I know Ross was mentioning earlier that with Ares 1, Orion would have to do a SM burn to get it to the ISS. Didn't know if that's the case with the J120.