The Soyuz is a very old design. Is the orbital module even useful when going to the ISS? Presumably you could use it to load additional cargo.It's worth noting that proposed russian replacements for the Soyuz look more like an american conical capsule design: https://en.wikipedia.org/wiki/Prospective_Piloted_Transport_System
I never considered the option of an Expandable Activity Module, but it makes a lot of sense. It has all the advantages of having an extra module, but without all the hassle. Would that require a Apollo style maneuver to get it from the trunk, or could it be already attached to the hatch, but folded, to be inflated in orbit?
I remember Gwynne Shotwell made a remark quite a while back. She said they had considered building an inflatable extension into Dragon. It would be attached at the top where the mating adapter sits and could be inflated once Dragon is on course. Unfortunately I would not know how to find that statement now.It seems they have moved past that though. Today it would be seen as a distraction from their direct way to the BFR/MCT design.
I'd love to go into space. I don't know about going to Mars—I don't like camping. But I would love to go to space for a couple days. What I'd love to have is some sort of inflatable structure that comes out of the top of Dragon—a clear inflatable structure. This is a visionary thing, not an engineering thing, but I can imagine popping out of the Dragon hatch into this clear sphere floating around in space. I don't know if I'll get the chance to go or not. It's unclear now whether SpaceX astronauts will fly or only NASA astronauts will fly, but I will make sure my employees are taken care of before me.
First of all, my apologies if this is something that has been already discussed in other threads....- Are the super dracos powerful enough to provide abort capabilities to the capsule, even if it has another module staked on top?
SpaceX hasn't indicated any interest in paying for such missions itself. It's focused on Mars, which will require substantially more than the small orbital module proposed here. Any excess funds SpaceX has will go to the Mars path, not this kind of orbital module.
Quote from: ChrisWilson68 on 11/05/2014 07:35 pmSpaceX hasn't indicated any interest in paying for such missions itself. It's focused on Mars, which will require substantially more than the small orbital module proposed here. Any excess funds SpaceX has will go to the Mars path, not this kind of orbital module.I've often wondered what that path is intended to be though. I feel like the current SpaceX roadmap is basically this:1) Crewed transport to Low Earth Orbit for ISS support2) ?3) Colonies on Mars!In all seriousness, is there any architecture being defined for beyond-LEO human flights? I don't know if SpaceX is hoping for a policy change and inclusion into a post-SLS redefined national exploration strategy. But I'd be curious to know if there's any serious thought being given to interim milestones including cislunar flights.
Quote from: moralec on 11/05/2014 07:20 pmFirst of all, my apologies if this is something that has been already discussed in other threads....- Are the super dracos powerful enough to provide abort capabilities to the capsule, even if it has another module staked on top? No, which makes the idea a non-starter.
Quote from: cdleonard on 11/05/2014 11:58 pmThe Soyuz is a very old design. Is the orbital module even useful when going to the ISS? Presumably you could use it to load additional cargo.It's worth noting that proposed russian replacements for the Soyuz look more like an american conical capsule design: https://en.wikipedia.org/wiki/Prospective_Piloted_Transport_SystemSure has a very similar outline to the dragon capsule. Seeing the development timeline, though, it may be just as likely that Dragon borrowed from it as vice versa.
Moralec asks an interesting question; it doesn't matter if SpaceX won't do it or if it isn't realistic to happen.As a thought exercise, I think there would be a lot of problems with putting an orbital module on top because of LAS impact and possible aerodynamic issues (needing a fairing).How about an Apollo style turn around and dock with an LEM approach? You could have an interstage that serves as an orbital module and then those other issues go away? A BEAM would be a great orbital module.
Quote from: guckyfan on 11/06/2014 04:18 amI remember Gwynne Shotwell made a remark quite a while back. She said they had considered building an inflatable extension into Dragon. It would be attached at the top where the mating adapter sits and could be inflated once Dragon is on course. Unfortunately I would not know how to find that statement now.It seems they have moved past that though. Today it would be seen as a distraction from their direct way to the BFR/MCT design.Heh, I looked it up. More of an "I think this would be cool" comment than a "we considered building this". It would be cool to have a porta-Bigelow with you somehow...
First of all, my apologies if this is something that has been already discussed in other threads. - What possible uses can you think of for a configuration like the one described above?
Quote from: Lars-J on 11/06/2014 05:25 amQuote from: moralec on 11/05/2014 07:20 pmFirst of all, my apologies if this is something that has been already discussed in other threads....- Are the super dracos powerful enough to provide abort capabilities to the capsule, even if it has another module staked on top? No, which makes the idea a non-starter.I've mused on this idea myself. Any orbital module would have to be flown in an extended-length trunk but attached to the upper stage so that the Dragon simply separates, transpositions and docks after reaching orbit. Something vaguely descended from BEAM is an obvious candidate. However, it would be a complex and expensive engineering task to turn a passive module into an operational free-flying orbital module with power, ECLSS and the like. There would have to be a serious customer willing to stump up the development cash.
It might be worth having a module that occupies the space and some roles of the trunk, but is mostly composed of the additional habitation module. The part immediately adjacent to the dragon, though, would be a simplified unfolding arm-type actuator module that moves the habitation module round onto the docking port. This is complicated, but it does avoid the detach/re-attach complications, since power feeds etc can run along the arm.Dragon's attitude control already copes with the challenges of trunk-on and trunk-off modes so this should be just another variation once the hab-module is attached.Your observations concerning cash and commitment stand unaltered
Thanks to all for the valuable replies. I was not aware of that fundamental difference between american and Russian spacecraft design.
For a US-based "crew to LEO" system, much depends on the approach NASA takes to LEO after ISS is decommissioned. One strong possibility is that NASA will encourage (and financially support) the establishment of commercial space stations.If that happens, having a Dragon Orbital Module that remains in orbit after the capsule returns could be a huge win.
Quote from: sdsds on 11/06/2014 08:24 pmFor a US-based "crew to LEO" system, much depends on the approach NASA takes to LEO after ISS is decommissioned. One strong possibility is that NASA will encourage (and financially support) the establishment of commercial space stations.If that happens, having a Dragon Orbital Module that remains in orbit after the capsule returns could be a huge win.The Tiangong solution. Put a CBM on each end of the orbital module and grow a space station with each mission.
The simple answer is that there IS NO NEED.Dragon 2 is just a taxi to get to a space station. Or to the Moon/L1/L2, at the most. That's just 3 days of free flight at most. And while small, it is already quite roomy compared to Soyuz.Dragon 2 will be the equivalent of an economical small car. Why are you trying to make it into an RV for work commutes?
First of all, my apologies if this is something that has been already discussed in other threads.How reasonable and feasible would it be for Space X to design and produce an Orbital Module for Dragon 2, in order to allow that manned capsule to perform longer missions, possibly beyond LOE (Moon, Lagrange Points, Etc.)? I'm thinking in a configuration similar to the one that is used by the Soyuz Spacecraft (image attached).
- Could the NDM (or the equivalent that is being developed by SpaceX) be used to joining both parts together?
Quote from: moralec on 11/05/2014 07:20 pmFirst of all, my apologies if this is something that has been already discussed in other threads.How reasonable and feasible would it be for Space X to design and produce an Orbital Module for Dragon 2, in order to allow that manned capsule to perform longer missions, possibly beyond LOE (Moon, Lagrange Points, Etc.)? I'm thinking in a configuration similar to the one that is used by the Soyuz Spacecraft (image attached).No, it would prevent the launch escape system from working. You would need to do something similar to Apollo where the Orbital Module gets launched beneath Dragon and then docks after they enter in orbit.Quote from: moralec on 11/05/2014 07:20 pm- Could the NDM (or the equivalent that is being developed by SpaceX) be used to joining both parts together?It's called the NASA Docking System (NDS).
Quote from: manboy on 11/10/2014 10:28 pmQuote from: moralec on 11/05/2014 07:20 pmFirst of all, my apologies if this is something that has been already discussed in other threads.How reasonable and feasible would it be for Space X to design and produce an Orbital Module for Dragon 2, in order to allow that manned capsule to perform longer missions, possibly beyond LOE (Moon, Lagrange Points, Etc.)? I'm thinking in a configuration similar to the one that is used by the Soyuz Spacecraft (image attached).No, it would prevent the launch escape system from working. You would need to do something similar to Apollo where the Orbital Module gets launched beneath Dragon and then docks after they enter in orbit.Quote from: moralec on 11/05/2014 07:20 pm- Could the NDM (or the equivalent that is being developed by SpaceX) be used to joining both parts together?It's called the NASA Docking System (NDS).The Japanese have a nice solution to this, at least on paper.The orbital module rides up behind the capsule, but attached by long arms.In case of an abort the orbital module is left behind.When they make it to orbit, the arms extend slightly, then swing the OM around to the front of the capsule, before retracting and berthing the OM to the capsule.No need to control two independent spacecraft and perform a docking.It was discussed on NSF back in 2009.
Does that really save weight and complexity compared to small thrusters and gyros?
Quote from: Comga on 11/24/2014 09:37 pmQuote from: manboy on 11/10/2014 10:28 pmQuote from: moralec on 11/05/2014 07:20 pmFirst of all, my apologies if this is something that has been already discussed in other threads.How reasonable and feasible would it be for Space X to design and produce an Orbital Module for Dragon 2, in order to allow that manned capsule to perform longer missions, possibly beyond LOE (Moon, Lagrange Points, Etc.)? I'm thinking in a configuration similar to the one that is used by the Soyuz Spacecraft (image attached).No, it would prevent the launch escape system from working. You would need to do something similar to Apollo where the Orbital Module gets launched beneath Dragon and then docks after they enter in orbit.Quote from: moralec on 11/05/2014 07:20 pm- Could the NDM (or the equivalent that is being developed by SpaceX) be used to joining both parts together?It's called the NASA Docking System (NDS).The Japanese have a nice solution to this, at least on paper.The orbital module rides up behind the capsule, but attached by long arms.In case of an abort the orbital module is left behind.When they make it to orbit, the arms extend slightly, then swing the OM around to the front of the capsule, before retracting and berthing the OM to the capsule.No need to control two independent spacecraft and perform a docking.It was discussed on NSF back in 2009.Does that really save weight and complexity compared to small thrusters and gyros?
If you want to add an orbital module to the top of Dragon and still have your Launch Escape System (LES) able to pull the crew off the rocket, why not do it like the Russians have with Soyuz for nearly 50 years?When a Soyuz does a launch abort, the LES rocket tower pulls the launch shroud, with the orbital module and descent module attached, off the rocket. When the shroud/OM/DM stack has cleared the rocket's blast area, the DM is separated from the OM/shroud assembly and drops away from it, and then the DM then pops its 'chute and lands "normally."-Doug (With my shield, not yet upon it)