A nomograph is a graphical calculating tool. It makes calculating things quick and easy, using simply a ruler.

I have created this one to compute time, distance and speed when preparing attacks with SH3 or SH4. Once you have tried it, it becomes essential to any attack!

Similar nomographs have been integrated into the SH3 map but I find a printed version much quicker to use, and also more precise.

(this image only display the right part of the page)

There is now two versions of the nomograph, one using metric units for distance (for use with SH3) and one using american units (for use with SH4, graduated both in yards and nm).

Download and print either of the following pdf files:

• Nomograph, Kriegsmarine version: nomograph_euro.pdf
• Nomograph, US Navy version: nomograph_us.pdf

Alternatively, you can download the nomographs in other formats:

• SVG files (vector format, can be resized/scaled without loss of quality), print it using for example Inkscape (for some reason, it appears blurry when printing with Firefox): nomograph_euro.svg and nomograph_us.svg
• The perl script used to generate the SVG files, if you want to easily modify the nomograph: nomograph.pl

The nomograph has three scales: time, distance and speed. Given any two of these data, the third can be read on the graph.

For example, when pursuing a target:

• On the SH3/SH4 map screen, plot two (or more) positions and note the time for each of them.
• Draw the line between the two positions and measure the distance between them (using SH3/SH4's line tool).
• With the times you noted, calculate the number of minutes between the two positions.
• Using a ruler, draw a line on the nomograph between the known DISTANCE, and the known TIME, you can read the target's SPEED (where your ruler intersects the SPEED scale)!

Of course, the reverse is also possible: given a time and a speed, you can deduce the distance, or given a distance and a speed, you can deduce the time.

The good thing is that it takes only 5 seconds to make the calculation using the nomograph!

I hope you will enjoy this tool, please send any remarks/suggestions to myself: nicolas (at) bonnefon (dot) org.