Some people consider the slide rule as an icon of computational obsolescence. I think the slide rule is alive an well in the artillery community in the form of a graphical firing table. Despite the Ukrainians having $50,000 fire direction computers to calculate data, soldiers in the field still use their fire sticks to double-check their solutions. And should electronic jamming cause the high tech to fail, an artillery officer can still deliver accurate and timely fire support.
My slide rule wouldn’t fit in to my pocket like my phone but when I carried it on top of my books, it was like a proud indicator that I was ready to roll into a heavy classroom setting.
The trusty slide rules used today calculate quadrant elevation and time-fuze settings. Those calculations are the same I did in the 1970s. And although slide rules will calculate only up to three places, when you’re launching the artillery rounds on the field today, the slipstick’s solutions of three places are more than accurate to create the right-sized blast crater.