Just another test. However... To me there is an issue with large diameter pressured tubes - the point where the tube connects to the top is affected by the su

Just another test. However... To me there is an issue with large diameter pressured tubes - the point where the tube connects to the top is affected by the surface area divided by the diameter. Obviously one of those scales linearly, and the other squared. That suggests to me (I'm definitely not a rocket scientist!) that the upper bound might be smaller than this diameter, or the weight will have to increase in order to beef up the strength of this point. Pretty interesting problem to deal with now that they are this far into the design. I'm sure there are many possible solutions, and it will be fun to see what they come up with.