BH Scientific Calculator - Speed, Time & Distance

Awesome "old-school-analog" calculator for super quick and easy computations of speed/time/distance. I *much* prefer this over using a calculator for paper navigation. And this one is notably slicker and more intuitive to use than the wheel type slide rules from Weems & Plath that seem to be so much more popular on this side of the pond (USA). Very glad to have found this one here on Amazon.BTW, note that this device is not limited to nautical calculations... Works just as well in units of statute miles & mph, or in kilometers & kph, as it does in nautical miles & knots, because of course the math is all the same if you stick to one set of units.Simple, quick, easy, intuitive, portable, versatile... What more could you ask?

Accurate and very easy to use. Much smaller and faster than the circular calculator from Weems & Plath. Unfortunately, the center slide seems to be made from a paper based card stock that would be easily damaged by water. Surprising in a nautical navigation tool.

I now need to determine how it works.

Didn't get to use it - bought it as a prize for a contest.

I never had named this thing a Calculator ruler