Notes: "The E-6B flight computer was invented in 1940 by Navy Lt. Philip Dalton. It was a further refinement of his earlier Model B, Mark VII, and Mark VIII flight computers. The E-6B name comes from the inventory number it was given by the military. Within two years the military had changed their inventory system and numbering scheme, and the former E-6B had a different number. That would happen a few more times, but for civilian pilots it was forever the E-6B (or E6-B or E6B, by companies trying to avoid Dalton’s trademark). This particular Dalton E-6B is an early one, as evidenced by the absence of density altitude on the slide rule side, and “computer” being misspelled “computor”. "
