Update on Boeing CST-100 Crew Program

Keith Reiley of The Boeing Company recently gave an update on the company’s progress on its CST-100 crew vehicle during the 14th Annual FAA Commercial Space Transportation Conference. I’ve excerpted some of the most interesting slides and images from his presentation.

Major Systems


  • The part of the slide you show has “weldless structure”, and there’s a mention of Delta spin form process on slide 13 (google turns up a patent on spinning tank hemispheres, so I’m assuming that’s what it is referring to). Is the entire crew compartment spun? Any more details on that?

  • John Turner

    In slide 9 we see the pressure vessel consists of a “pot and lid” set of two massive workpieces that bolt together; see the lower-right image of the slide where nut-and-bolt fasteners appear every 2in/50mm or so along the flanges?

  • John Turner

    Remarkably the workpieces would have originally been quite heavy-gauge metal, perhaps over an 1-3/8 inches thick when forged. They were then whittled away at on a machine tool to create the hundreds of triangular recesses visible in the photos, taking away over ninety percent of the workpiece’s as-forged mass.

    The upper-right photo on slide 9 shows us the top workpiece partway through this epic whittling operation. We can see a mound of cut metal chips heaped inside the hatchway, and we see that the cylinder-section skirt under the conical section has yet to be machined into triangles. The triangles in the conical section are undersized and unfinished, suggesting the photo was taken while “hogging” the workpiece down to near its final dimensions with additional toolpasses yet needed to refine the “lands” between triangles into neatly finished ribs with centerdrilled nodes as seen in the lower photo. It would have taken weeks to whittle this workpiece at a cost of hundreds of dollars an hour.

    The complete assembly is not just the top “blue lid” and bottom “green pot” but eight bolted-on hardpoints that function like engine mounts to suspend the vessel on a ring (not pictured) and four machined metal gussets that tie to the “purple pipe” cylinder-section pressure tunnel that pokes out top (while providing more hardpoint mounts for the capsule’s aerodynamic skin and for the parachutes and abort rockets). The bottom ring would both serve to support the capsule atop a launch adapter and to seat the heatshield.

    As least, that’s what I get out of ogling the rather lo-rez slide Boeing provided.


  • John Turner

    Oops! I just checked and there are six lower hardpoint blocks not eight. I also failed to mention the eight bar-section gussets interspersed with the four big wrench-shaped gussets.