Originally Posted by aeppel_cpm

I understand the Terrier and Nike fins aren’t the same. To my eye, it looks like the Terrier Sandhawk-17 in Fig 1 is specifying Nike M12 fins on the -Terrier- booster. Likely for a little more stability with those fat payload fins on the sustainer.

And I think the BT-3 fins -are- the first ones you posted. While you haven’t posted a RIM-2C (aka BT-3) you can see that the D seems to have extensions to the span. And the F and HTR seem to have the D planiform with a double wedge profile, rather than the diamond pictured in the D and the drawings/photos higher up the thread.

I’m thinking that as they increased the Cp contributing area in the Navy sustainer, they increased the span on the Terrier. I’m guessing the Sandhawk-17 predates that and they just borrowed appropriate Nike fins. The planiforms of the Sandhawk fins sure look borrowed from the Tomahawk- though I’m guessing they are upscaled 13/9 and 17/12. (But I haven’t done the math)