From: Doug Faunt
Date: 2021 Oct 30, 13:18 -0700
World War II
American Air and Nautical Almanacs
Columbia University's Wallace Eckert
From reading those recollections of Sadler posted here I wouldn't call what was being done in 1936 "advent of first digital computers" as Karl remarks in his book. Karl says this about the US attempt to produce HO 214 but Sadler makes it sound like it was the British who did the computations for subsequent volumes. It's all a bit murky and it may have been considered classified which is why there is no real evidence on how it was done.