13 thoughts on “Orion”

  1. “GAO also found that part of the cost increase can be attributed to the switch from a single-piece heat shield to one that uses blocks of materials.”

    I thought one reason for the switch from the older heat shield design was to save costs incurred by its labor intensive construction. The old design’s “honeycomb structure had 320,000 tiny cells that were individually filled by hand with an ablative material called Avcoat”.

    And hadn’t they decided to shift to the new heat shield design before flying EFT-1 in December 2014, where, for the low, low cost of a Delta IV Heavy, they tested the old, even-then-obsolete heat shield design?

    1. What?

      The EFT-1 Orion was basically a mock-up inside (no life support, etc) and I though the whole idea was to test the heat shield, but that was one they didn’t play on flying with anyway?

      What on earth was the point of EFT 1??? If it was merely to make NASA look both stupid and wasteful, then they succeeded!

      I’ve long opposed SLS, but I’ve also long been even more outraged by Orion; its design makes no sense at all. Why on earth make what’s basically a hab and build it like a rock to withstand high speed reentry, which makes it far too massive to be useful for anything beyond LEO? Better by far to go the Soyuz route; a small spherical RV that’s just an RV, then size the actual hab (which Orion will need anyway to go beyond the moon) to suit, thus allowing a far lower mass hab than one designed to reenter from interplanetary velocities.

      Orion may well be the one space item that makes even less sense than SLS, and that’s quite an accomplishment!

      1. I absolutely agree with you regarding Orion. Unless your craft is reusable, make your reentry vehicle as small as possible and pair it with a spacious but lightweight habitat module.

        Engineers recommend changes to Orion heat shield [Spaceflight Now, 2014-11-05 (one month prior to EFT-1)], quotes a Lockheed Martin engineer as saying that the new block architecture heat shield uses the same material as the old one. “It’s still Avcoat, so what we will test on the first mission and with the second mission is the difference in the rescission rate. It’s an ablative material. We expect it to ablate. Whether it ablates the same as a block or a little bit different than the honeycomb — you might expect minor variations, but you wouldn’t expect major variations.”

        And, even if the heat shield was the primary component being tested (and the reason for the trajectory flown), it did test other systems, such as “Computers, guidance systems, software, and the Orion spacecraft’s launcher adapter and separation systems.”

        Still, the circumstances of the test seemed strange.

      2. “I’ve long opposed SLS, but I’ve also long been even more outraged by Orion; its design makes no sense at all.”

        Everything bad about Orion originates in ex NASA administrator Griffin’s “Project Constellation” back-to-the-moon mission architecture. I think he deliberately required an oversized CEV to rationalize his crazy Ares I rocket.

        Hey, it could be even worse. At one point the Orion capsule was going to be 5.5 meters in diameter! And the plan was to use that bloated CEV as the return vehicle for Mars missions.

        NASA aren’t complete idiots. Sure the hybrid chem/SEP “Deep Space Transport” concept might be a slow deathtrap to Mars (zero gee is a bitch!). But at least the mass budget works out since the DST won’t drag that Orion lump to Mars and back. Now the Orion (+SLS) is just a gold-plated space-taxi to the DST.

    1. None…
      The NASA bureaucracy will never ‘human rate’ a competing design.
      (/sarc, though I wish it wasn’t)

  2. Why should Lockheed or any other of tge SLS/Orion contractors worry about change orders, cost overruns, or schedule slips? Cost plus, baby!

    1. The Orion capsule isn’t even the Lockheed design that won the competition. Immediately after winning the bid; NASA took LM over to UofH ClearLake and told them what the “real” design was going to be. That’s after LM dumped their lifting body design for a capsule after Griffin gave his press briefing announcing that the next vehicle would be a capsule. At this point, I see Orion as a MacGuffin.

    1. Dragon 2 is about 14k pounds – so 7 tons. I don’t think Dragon is optimum for interplanetary, because it’s still quite heavy, and for interplanetary that’s a lot of mass to push through a lot of delta-v.

      A Soyuz RV module is about 3 tons (but only hols 3 people).
      For comparison, Orion is 23 tons (just for the capsule).

      My take; Dragon isn’t optimum. But it exists and it’s far, far better than Orion where it counts (mass).

      1. I have never understood the talk about Orion, or any other capsule, being used for any voyage longer than about a week. It’s the equivalent of a group of people living in a SUV for an extended length of time, never getting outside.

        How exactly do you prevent the justifiable homicides that are going happen in something that crowded for that long?

      2. I think SpaceX claims the heatshield for the Dragon capsule is adequate for even Mars return speeds.

        I think total mass for Soyuz is about 8,000 kg. But total maneuver is only around 300 m/s total.

        Orion numbers are all over the place, depending upon when you look, gross mass 26,565 kg. The latest figure I’ve seen for the capsule was over 10,400 kg (holy crap!). Add to that the hefty 15,450 kg propellant laden service module for the 1,333 m/s maneuvering capacity, needed for return from lunar orbit.

  3. A lot seems to make so much more sense when you look at SLS, Orion, and NASA as a whole, as programs to funnel tax money to selected Congressional districts.

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