[aerohead]

This seems to be a subject we can never escape from and I climbed down into the deep dungeon of aerodynamics and present the following to anyone interested in "golf-balling" there vehicle in the quest for lower drag.

The data is from the Third Reich:the research was reported by Heinrich,"Wind-Tunnel Investigation of a Wing With Bombs,ZWB UM 4574 (FGZ 1944),as presented by S.F.Hoerner,Chapter 8,page 132-133,"Aerodynamic Drag",1951. Here's the gist of it.

A 2,500 kg bomb,with Cd o.04 increases to Cd0.14 with addition of tail fins,stiffening-ring,and propeller fuse. If a "nose ring" is attached to the nose of bomb to facilitate water entry for ship bombing,the Cd jumps to 0.20 ( a 42 % increase in drag ).

All values are for sub-sonic,super-critical Reynold's Number,full turbulent boundary layer flow. If you've seen fluids texts and photos from the U.S.Navy' David Taylor Tow Basin facility in Maryland,and seen underwater photos of (very smooth)bowling balls with sand glued to the leading edge,or a "ring" attached at same location,to trip the boundary layer into turbulent flow( a good thing!),then from the "bomb" example,you may appreciate the significance of "tripping" a tripped boundary layer and the added drag it could induce.

My advice is: Don't go there!