Jan 262017

Just sold on EBay (not to me, sadly) is a kinda rough Topping display model of a little known proposed variant of the Atlas space launcher, the SLV-3X. This design had a widened body, from ten feet to 12 feet, 7 inches. This allowed for more propellant to be carried without lengthening the vehicle, meaning that the existing launch infrastructure could be used. Additionally, the MA-5 sustainer rocket engine would be replaced with a higher thrust H-1D engine. See HERE for stats.

ebay 2017-01-26 fat atlas 1

The SDASM Flickr account has a nice illustration of the SLV-3X/Centaur. See their site for the higher rez image.

 Posted by at 7:41 pm
  • markus baur

    this looks like it still uses the “original” atlas “boat tail” / thrust structure – can you confirm that?

  • publiusr

    The Delta Dart enjoyed “‘wasp-waisted’ shaping due to area rule considerations”

    I wonder if this would have helped this Atlas.

    • Siergen

      I hadn’t thought of that. Although I doubt launch vehicles spend much time at transonic speeds, reducing drag at those speeds (and thus dynamic pressures and structural stresses) might be beneficial.

    • Paul Roberts

      No, it wouldn’t. The wasp waisting of 50’s fighters brings in the fuselage cross sectional area to account for the additional cross section area of the wings and tail. The aim is to keep the total cross sectional area of any lateral section from front to back progressing in a smoothly increasing and then decreasing value no matter what the actual shape of the cross section might be.

      An area ruled rocket booster would look like a 50’s idea of a rocket fuselage:

      The minute you have a cylindrical fuselage, you’ve thrown area ruling out the window.
      And Siergen is right, boosters don’t spend enough time at transonic speeds and high enough atmospheric density to offset the structural and manufacturing problems in designing actual boosters to “bottle rocket” shapes. 🙂

      If they did, rockets would be shaped that way already. Believe me, booster design is a pretty optimised technology by this point. If there was anything worthwhile in it, you’d see modern boosters area ruled.

      • publiusr

        It would be charming to see at least one ITS something have that 50’s look…