Hello there,
I've seen numerous threads discussing naval "accuracy", but they always lead to answers about Fire Control Systems and I want to know instead what shot fall patterns are like.
Where, under ideal circumstances, would my shells land if I just shot at the water "X" distance away with "Y" weapon? I hope you understand my meaning and any help would be much appreciated.
Many thanks,
TheResplendency
What you want to look up is circle of probable error (the military term for artillery dispersion) where 50% of projectiles will land in the circle. This accounts for “fliers” (that random shell that goes off on its own) and provides a more useable figure for practice accuracy like hitting a ship with a broadside or fire support effectiveness.
The Iowa’s was about 150yards at near max range
For example, during test shoots off Crete in 1987, fifteen shells were fired from 34,000 yards (31,900 m), five from the right gun of each turret. The pattern size was 220 yards (200 m), 0.64% of the total range. 14 out of the 15 landed within 250 yards (230 m) of the center of the pattern and 8 were within 150 yards (140 m). Shell-to-shell dispersion was 123 yards (112 m), 0.36% of total range.
For reference the max range of the Iowa’s guns was ~35,000-38,000y
Current naval 5in is 50m give or take without guided shells. See pg19 one source. That’s also the same error from my old OS testing manuals which I don’t have access to anymore
I can’t find a better source for the IJN Yamato as a comparison. Most say “about 500y” for total dispersion of the 18in gun at max range instead of COE but if true that means the Iowa’s guns were maybe twice as accurate (moreso because USN mechanical computing and radar guidance was notably better. The IJN prioritized optical ranging until the end)