I saw this photo of a B-17G-35VE "Daddy's Delight",303rd BG mid 1944 in England, and am not sure what type of tyre tread this is? Is it the common "diamond tread" type?
I've seen that tread before. If I can find a better/more clear pic, I'll post. For lack of a better term, I'd describe it as an "irregular" or jagged block tread.
Quick look through my files.....found this. Not much better than the O/P posted unfortunately.... If you enlarge the picture, you'll see the tread much more clearly.