Believe it or not the blimp is the most

streamlined shape you can have for subsonic speeds.

Jim Brewer wrote:

Paul,
I'm no engineer, so help me out here with some references that defines the
"blimp" shape and why your claim would be so.

Jim Brewer

This was discovered and confirmed years and years ago purely by many 
trial and error experiments.  It is a combination of what is called 
form drag and skin friction drag. From drag has to do with the shape 
of the object and skin friction with the total surface area of an object.

There are two optimum shapes. One is based on the minimum drag for
a given enclosed volume. The other is based on the minimum drag for a given
frontal area. They both look like blimps. Frontal area is not the shape of the front of the object. Frontal area is technically defined as the maximum cross sectional area of a given shape. The max frontal area of an object can be two thirds back along its length but that may not be the lowest drag 
position. 

The bible on this sort of thing was written by Dr-Ing. Sighard F Hoerner
called Fluid-Dynamic Drag and published by the author in 1965. I think it
is out of print but you may be able to find a used copy on the Internet. 
My new copy bought from the author in the late 60's is signed by Dr. 
Hoerner himself who is now deceased. BTW Klause Savier claims he dated
Dr. Hoerner's daughter at one time :-)

Paul Lamar
 
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