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aerohead,
Zepellin and Jaray did not lead the airship shaping part of the game. Fuhrman in 1906 published a shape and drag calculation results that clearly set the standard, which did not get picked up until 1913 on the LZ17, according to my looking at the shapes of the early airships; where Zepellin made long cylinders fitted with nose and tail shapes that helped a lot, but the ideal drag form. Jaray might have 'designed' the LZ120 and even measured it in a wind tunnel, but this came some years after 1914 when he first started to work there.
In parallel with Zepellin manufacturing oriented work, activities by Prandtl and Fuhrman (student of Prandtl) took place at a more theoretical laboratory level. Prandtl is referred to in some of my books as the father of modern aerodynamics, whatever that means. He is also credited with the Prandtl wing used by British and German WWII aircraft. My old fluid dynamics book by Rouse and Howe 1960 shows Fuhrman reported data and includes that airship on the comprehensive plot of drag coefficients for various shapes. Data there shows Cd for that Fuhrman airship for various Reynolds number values, but generally these range around .05.
The NACA wind tunnel tests offer the best info I can find on the airship, and the USS Akron is the most thoroughly tested model, particularly the ZRS-4 model. Getting the exact Cd in our modern terms is not straightforward, since most of the data reported was in a different form of Cd where the coefficient is with respect to, not frontal area, but the cube root of volume squared. This gives numbers like .02 which can not be directly compared with the kind of numbers we talk about here.
I do not think there is any difference between the USS Akron and USS Los Angeles as far as basic shape goes. I especially liked the Akron data because it was done on a scale model of the airship, but the model is about the size of the car I am interested in, so there is much less concern about accuracy of the scaling process.
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