Comment by watersb
3 months ago
A sort of non-logarithmic slide rule, the E6B Flight Computer, was still in use when I was a student pilot 20 years ago. I still carry one: they don't require electricity (although using one in the dark requires a light source).
The main part of the E6B is a very standard logarithmic slide rule. Having it loop unto itself is a neat trick but very ancient.
But perhaps you were referring to one of the many other parts of the E6B which I am not familiar with.