Earth Departure Mission Planning & Execution Q&A

• Earth Departure Mission Planning & Execution Q&A by Belisarius on 15 Mar, 2012 20:49
• Hey, folks.  New guy, here, so please let me know if I make some kind of inadvertent internet gaffe. 
  
  I've been trying to dig up some information on absolute minimum theoretical mission planning > launch periods...turns out it's a little harder to find the answer than expected. This seemed a better place than most to take a shot in the dark.
  
  In a nutshell, I'm trying to determine just how compressed a schedule NASA could follow if it became absolutely necessary to launch a manned earth-departure mission to meet but not exceed the requirements of a Selenocentric orbit. For simplicity's sake, let's assume we can write a blank check...and I know that's unrealistic from a budget standpoint, but it will suffice for my purposes. For this scenario, one can also assume full cooperation from ESA and JAXA at bare minimum.
  
  Not fully up to date on currently proposed systems capable of delivering an MPCV to an elliptical lunar orbit (I have been looking at SLS as a likely candidate, but as a layman I don't have a very reassuring frame of reference), but I assume most of the hardware would need to be either OTS, repurposed, or built at something bordering on an insane time schedule. Quality control and safety become complicating factors, certainly.
  
  So...in an even smaller nutshell, how soon could we put a manned spacecraft in lunar orbit, given the current absence of an operational lift system of the requisite scale, except on paper? I hope I don't have to add "theoretically" as a caveat. 
  
  I know this question is more scalpel than broadsword, but I honestly don't know where else to go with this research. Any tips, advice, or pure conjecture would be greatly appreciated.
  
  
  ~Belisarius
• #1 by QuantumG on 16 Mar, 2012 02:04
• If you're removing restrictions on budget, why not also remove the requirement that NASA be involved? Take your big hypothetical check to the Russians and launch next month.. or knock on SpaceX's door and launch by the end of the year.
  
  If you insist on having NASA in the driver's seat then you're going to have to discuss the political situation in your hypothetical scenario.
  
• #2 by Belisarius on 16 Mar, 2012 03:41
• Good point.  To be clear, I'm trying to put together research for a fictional story. Perhaps I should have just laid that out first, as it sets the context a little more efficiently.
  
  The political situation is complex, in that multiple parties are interested in reaching the same goal in the same timeframe...that being observation and contact with an NEO in lunar orbit.
  
  Basically, the Russians are sending their own mission up, and a private aerospace corporation is making its own bid as well.  We're talking about an extreme situation.  This is clearly unrealistic, but I'm drawing a fine line between "getting it right" and keeping the story interesting for a general audience.
  
  I know it's worse than sketchy, but I'm trying my best to make it feel real.  I'm not an engineer, astronaut, or scientist, and I don't have a technical background (at least, not when it comes to space exploration).  That means I have to overcome a lot of limitations. 
  
  Obviously professionals are going to write all this off as science fiction, but that's what I'm shooting for.  If it draws the audience in and allows them to suspend their disbelief, I've succeeded.  It's more of a personal goal not to annoy the professionals (too much) if I can avoid it. 
  
  
  ~Belisarius
  
  
   
• #3 by Robotbeat on 16 Mar, 2012 03:51
• No budget limit? Hard to say. Orion could possibly launch manned on Delta IV Heavy (without a fully tested LAS, though possibly still partially functional) if it had a functional service module.
  
  It's the service module that'd likely be the pacing item. Putting a few solids on a Delta IV Heavy would also be possible, pushing up the payload capability enough to probably launch a full Delta IV Heavy upper stage (perhaps slightly stretched?) with an NDS docking port on it in a pretty short timeframe... IF budget were no concern (ULA has been studying an upgraded Delta IV Heavy for a long time).
  
  There's also the possibility of Atlas V Heavy, which would take about 40 months until first launch if you decided on it TODAY (according to ULA). That'd put you towards the end of 2015, and would give you an extra launch pad, perhaps to launch an Orion with a more full service module.
  
  I have no idea how fast an Orion service module could be completed, but the other parts could be finished pretty fast, and there's already an Orion being built right now that conceivably could be outfitted with stuff needed to support the crew.
  
  I don't know, maybe late 2015 could be done with a dual-launch approach (Atlas V Heavy and Delta IV Heavy, since it'd give you the ability to have two pads so the crew on the first launch of Orion wouldn't have to sit around while you turned around the pad) though problems and delays basically always turn up in things like this. It'd be very risky since you wouldn't really be able to afford the time it takes to do test launches, but at least the basic launch vehicles exist and are very reliable already.
  
  Realistically, 2017. At that point, SLS becomes an option (though I still think that's going to end up more difficult schedule-wise than people think). You could squeeze out more performance out of SLS if you ignored core disposal, added the 5th SSME, and ate into your margin. Lack of any test flights would also be risky there, as well... arguably more risky, since it's more of a new launch vehicle.
  
  (You could do a dual-launch approach without Atlas V Heavy... Launch the crew first in the Orion, launch another Delta IV Heavy--perhaps upgraded--days later with a full Delta IV Heavy as a payload and do a quick rendezvous and docking and do a burn to high lunar orbit eyeballs-out, then doing another burn with the Orion after disposing of the D4H upper, perhaps after another pass for better performance.)
  
  Doing it with Delta IV Heavy has the advantage that Orion is already supposed to launch unmanned on the Delta IV Heavy in 2014, though without a functional service module.
• #4 by Belisarius on 16 Mar, 2012 04:18
• Wow, a lot of great information in there, Robotbeat.  Much appreciated.  More detail than I expected on such short notice (not that I'm complaining).
  
  What if we moved the setting of the story forward to c. 2019 or 2020?  Assuming development of SLS or another system progresses modestly in the next seven years...
  
  In other words, if all components of the system exist in a more tangible form, how might that impact the amount of time from mission inception to launch?
  
  
  ~Belisarius
• #5 by Robotbeat on 16 Mar, 2012 04:47
• Quote from: Belisarius on 16 Mar, 2012 04:18

  Wow, a lot of great information in there, Robotbeat.  Much appreciated.  More detail than I expected on such short notice (not that I'm complaining).
  
  What if we moved the setting of the story forward to c. 2019 or 2020?  Assuming development of SLS or another system progresses modestly in the next seven years...
  
  In other words, if all components of the system exist in a more tangible form, how might that impact the amount of time from mission inception to launch?
  ~Belisarius
  

  There's already supposed to be a manned SLS/Orion launch to something like high lunar orbit in 2021 (or 2019, if you're optimistic), following an unmanned launch in 2017. (You know that, right? For some reason, everyone in America seems to think NASA is canceled...)
  
  Your best chance would be to re-purpose an existing SLS launch. Usually, it takes years to plan such a mission. SLS launches are going to be only once every few years at first, using left over Shuttle parts.