1. With Ares I, the basic rocket is so cheap that if the upper stage is lost (and assuming they keep the 1st stage and the capsule re-usable) you may really only lose the consumables, abort system, and the upper stage; Ares I and Orion will be safer than Mercury, Gemini, and Apollo were. I do not care for Ares or Orion, but even I can see and accept that.
Quote from: MrTim on 06/18/2008 01:45 pm 1. With Ares I, the basic rocket is so cheap that if the upper stage is lost (and assuming they keep the 1st stage and the capsule re-usable) you may really only lose the consumables, abort system, and the upper stage; Ares I and Orion will be safer than Mercury, Gemini, and Apollo were. I do not care for Ares or Orion, but even I can see and accept that. 1. It isn't cheap. Most of the money is in the second stage. What is reused on the first stage is insignifican
2. That can't be said at the moment.
To Mr. Tim:Considering how many dual and even single fault tolerant primary subsystems in the Orion have been left on the parking lot due to the inadequate payload capacity of the current Ares-I rocket,
inlcuding the little known fact that if Orion is in transiit to/from or orbiting the Moon and loses one of its solar power photovoltaic arrays due to just one of several credible faliure modes that the crew will die before they can get back to Earth due to a total power failure after xx-hours, tells me that the current Constellation program, along with its Ares and Orion projects are broken in a very fundamental way. They make continuing flying the Space Shuttle look better and better every day this evollving fiasco continues...
1. D-IV Heavy would be cheaper.
2. Since the Ares I doesn't not use the legacy SRM, it won't be as safe as a liquid stage.
Quote from: Jim on 06/19/2008 01:54 pm1. D-IV Heavy would be cheaper.An entire 3-core Delta 4 Heavy will be cheaper (unit cost, not all the R&D) than a single Ares I upper-stage? I'd love to see the accounting on that.
Quote from: MrTim on 06/19/2008 02:11 pmQuote from: Jim on 06/19/2008 01:54 pm1. D-IV Heavy would be cheaper.An entire 3-core Delta 4 Heavy will be cheaper (unit cost, not all the R&D) than a single Ares I upper-stage? I'd love to see the accounting on that.I would like to see some numbers on the D4 claim. However, you do have to remember, while the first stage of Ares I is recovered, it isn't free. There is refurbishment costs to take into account.
Another thing to consider here is whether either vehicle can accomplish the desired missions. Delta IV has the edge since it can be expanded beyond the capabilities of the Ares 1, which is limited by the SRM first stage.Personally, I'm in favor of developing the EELVs further because those rockets can be used for other things than NASA missions. So a modestly more expensive Delta IV Heavy and more expensive Atlas V Heavy would in my humble opinion be justified on those grounds alone. It'd also be an opportunity to unmake the ULA and introduce some competition into the 20-25 ton range again.
I'm suppose I'm way outside the box, but if we're married to a single-SRB crew launch solution for Orion, information seems to suggest the outside-of-the-box is in play.
OK... completely showing my armchair rocket-builder ineptitude here, but I'll pose my question regardless.The SSME was the original engine for Ares-1, but it was dropped due to the difficulty discovered in modifying it for air-start.STS never needed it for air-start, since it lights them on the ground.Could an Ares-I "stick" do the same thing? i.e. mount the SSME, or some other engine(s), on the upperstage in such a way that you could start it on the ground?
Quote from: BogoMIPS on 06/22/2008 10:31 pmI'm suppose I'm way outside the box, but if we're married to a single-SRB crew launch solution for Orion, information seems to suggest the outside-of-the-box is in play.What information? NASA's says Ares I is meeting its design goals. Why would the Agency need to consider an alternative to a design that is meeting its goals? - Ed Kyle
Quote from: edkyle99 on 06/23/2008 03:07 amQuote from: BogoMIPS on 06/22/2008 10:31 pmI'm suppose I'm way outside the box, but if we're married to a single-SRB crew launch solution for Orion, information seems to suggest the outside-of-the-box is in play.What information? NASA's says Ares I is meeting its design goals. Why would the Agency need to consider an alternative to a design that is meeting its goals? - Ed KyleAres-I performance was #4 on the project top risks matrix in May. The data is on L2. 4x4 risk.
NASA won't cancel the program. NASA almost never cancels programs.