Actually, No, This Wasn’t Done With A Slide Rule

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5 pointsznmeb3 comments

Even if mainframe computers hadn't been available, it would have been done like the Manhattan Project was, by many human computers at electro-mechanical calculators. Slide rules are to imprecise for actual orbital calculations.

Yes, the Manhattan Project number crunching was mostly done by humans on mechanical calculators. There were some electromechanical machines available to them.

After the war, though, some of the calculations for the "super" - the Hydrogen Bomb - were done on electronic machines. In particular, there was a concern that the Super might ignite the atmosphere and the calculations to check that were a bit much for rooms full of people coordinated by pneumatic tubes.

I just looked through the paper by Konopinski, Marvin, and Teller which works through those calculations. http://www.fas.org/sgp/othergov/doe/lanl/docs1/00329010.pdf . I don't see any mention of any use of artificial calculation devices.

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