Why not Graphical Sight Reduction?

Extract

Mr. J. B. Parker, in his review of Sight Reduction Tables for Air Navigation, published on pages 98–103 of Vol. VII of this Journal, states that the time required by him to resolve a three-star fix by means of A.P. 3270 is 10 minutes (p. 100). He comments on the ‘errors due to the plotted fix being a hundred or more miles behind the aircraft's position’ (p. 101). Later he says: ‘An accuracy of sight reduction of anything better than certainly 5 minutes of arc, and more logically 10 minutes of arc, will therefore be wasted on a navigator flying with present-day instruments in a fast modern aircraft in high latitudes’ (p. 102).