The crew sleeping quarters habitat is surrounded by LH LOX tanks. Not described but I think propulsion stage is ACES based which would be fuelled when needed. I'm sure how they plan to keep LH cool for up to 2yrs. In deepspace with enough insulation and sunshade it maybe possible but this design doesn't have sunshade plus it will be exposed to heat radiated from Mars.
If the habitat stays in Mars capture, the DV requirements are not that demanding, 4km/s round trip from EML2. Using ACES as propulsion approx 140-150t of fuel would be required for every 100t of equipment doing round trip. That is approx 10 Vulcan launches for the fuel.
Quote from: Proponent on 08/01/2016 01:08 amThe ESD Budget Availability Scenarios produced in 2011 indicate a cost of about $2.6 billion (in FY2025 dollars) for one 130-tonne SLS launch per year, and $3 billion for one 130-tonne and one 70-tonne launch per year. To my knowledge, that's the only hard data we have on what SLS will cost to operate (and note that it's an increase over the annual budget during development), but it's not very hard. A figure of $500 million has definitely been floated by NASA, but it seems that could only be a marginal cost, and it may be no more than a hope.From the American Institute of Aeronautics 2012 Conference. Quote"We've estimated somewhere around the $500 million number is what an average cost per flight is," SLS deputy project manager Jody Singer, of NASA's Marshall Space Flight Center in Huntsville, Ala., said Tuesday during a presentation at the American Institute of Aeronautics and Astronautics’ SPACE 2012 conference in Pasadena, Calif."The cost of SLS per flight has not quadrupled since this statement was made.
The ESD Budget Availability Scenarios produced in 2011 indicate a cost of about $2.6 billion (in FY2025 dollars) for one 130-tonne SLS launch per year, and $3 billion for one 130-tonne and one 70-tonne launch per year. To my knowledge, that's the only hard data we have on what SLS will cost to operate (and note that it's an increase over the annual budget during development), but it's not very hard. A figure of $500 million has definitely been floated by NASA, but it seems that could only be a marginal cost, and it may be no more than a hope.
"We've estimated somewhere around the $500 million number is what an average cost per flight is," SLS deputy project manager Jody Singer, of NASA's Marshall Space Flight Center in Huntsville, Ala., said Tuesday during a presentation at the American Institute of Aeronautics and Astronautics’ SPACE 2012 conference in Pasadena, Calif."
Quote from: Khadgars on 08/01/2016 01:23 amQuote from: Proponent on 08/01/2016 01:08 amThe ESD Budget Availability Scenarios produced in 2011 indicate a cost of about $2.6 billion (in FY2025 dollars) for one 130-tonne SLS launch per year, and $3 billion for one 130-tonne and one 70-tonne launch per year. To my knowledge, that's the only hard data we have on what SLS will cost to operate (and note that it's an increase over the annual budget during development), but it's not very hard. A figure of $500 million has definitely been floated by NASA, but it seems that could only be a marginal cost, and it may be no more than a hope.From the American Institute of Aeronautics 2012 Conference. Quote"We've estimated somewhere around the $500 million number is what an average cost per flight is," SLS deputy project manager Jody Singer, of NASA's Marshall Space Flight Center in Huntsville, Ala., said Tuesday during a presentation at the American Institute of Aeronautics and Astronautics’ SPACE 2012 conference in Pasadena, Calif."The cost of SLS per flight has not quadrupled since this statement was made.Ok so I take it that $500 Million average cost per flight ignores any fixed costs to support the SLS? I have never seen NASA float a number that you can get 2 SLS launches per year with a total cost of $1 Billion. That is the problem with a low flight rate LV, your fixed costs will be larger than your marginal per flight cost.
So you would include fixed/development cost for NASA, but when referencing SpaceX and other launch providers you only reference per flight cost?Much of the fixed cost for NASA would still be there even if SLS didn't exist.
I'm sure how they plan to keep LH cool for up to 2yrs. In deepspace with enough insulation and sunshade it maybe possible but this design doesn't have sunshade plus it will be exposed to heat radiated from Mars.
NASA always assumes ridiculously heavy stages. Nothing you'd ever see in the final draft of a mission concept would ever assume ACES-like mass fraction.Lockheed may not be so unrealistic, though.
Sorry about starting a firestorm. But what I was trying to point out is that LM's proposed mission architecture is not really tied to SLS, and likely more affordable if it was not. All the mission elements at <34mt each would fit on a Vulcan/ACES including Orion. Only the operational costs and mission rates would differ but not the development costs which would be the same regardless of LV. Even if SLS "goes away" the mission architecture is still viable by LM selling Orion's commercially flying on a Vulcan/ACES distributed launch.My point is that this architecture is not tied to SLS other than by statements of its use. To pitch to NASA by specifying SLS is a positive in getting support for the mission architecture.