Following Ross' suggestion I've plugged airminded itself into the Google Ngram Viewer (for British English over 1920-2000 with a smoothing of 3). The word wasn't used until c. 1925 and grew in popularity until the end of the Second World War. It then began its long descent. Around 1960 its heyday was definitely over and by the late 1990s it was less popular than almost ever before. There's a noticeable dip in the years around 1940, which makes me wonder if the menace of aviation had temporarily overwhelmed its promise. But that's probably reading too much into it.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Permissions beyond the scope of this license may be available at http://airminded.org/copyright/.