r82ko

hope this pic from creator of this mod helps you a little.

30 узлов - 30 knots

5 секунд - 5 seconds

And little addition here. With two scales you can easily calculate lead for speeds 40 knt by multiplying lower scale ×2,for 25 knt you take middle between higher and lower scale, and for 35 kn you can take middle between higher and ×2 multiplied (for 40 knt) lower scale.

Hello. If you asking about nomogram crosshair here is some info:

Upper scale graduated for 30 knot speed in seconds for shells flytime. So if you see target with known speed of 30 knots and shells will fly to it 5 sec, aim at 5 on upper scale

Lower is the same but for 20 knot speed