I've had this tab open for days. Now I know why.
http://www.hisutton.com/images/Fr_G20_Prototype.jpg
I thought it was for that landing gear.
The airships needed higher power/volume ratio and more rigidity. The optimal aeroform can have it's back broken. The smallest volume would be acquired with a hot Hydrogen partial vacuum. It could be surrounded by a thermal/electrical insulating blanket of Helium or steam. Rigidity could be acquired with a tensegrity geodesic structure. That might look like this:
This is an externally braced icosahedron for clarity. Higher frequencies would have a quasi-compound curve.