Origin of Limit Manoeuvring Load Factor Formula
The limit manoeuvring load factors for aeroplanes in many of the relevant certification specifications are based on the formula n = 2.1 + (24000 / W + 10000). I could trace this formula back to the Chicago Conference, where it was tabled by the American delegation as a draft proposal for the technical annexes to the Convention. The formula itself was devised by the US Civil Aeronautics Board, who later included it in the then new Part 03 of the Civil Air Regulations for non-transport airplanes (a predecessor of FAR Part 23).
I just cannot seem to find a single source document, e. g. a technical report or explanatory note, that discusses the mathematical derivation of the formula. Any help would be much appreciated.