PolarSys B612 font family - https://github.com/polarsys/b612
In 2010, Airbus initiated a research collaboration with ENAC and Université de Toulouse III on a prospective study to define and validate an “Aeronautical Font”: the challenge was to improve the display of information on the cockpit screens, in particular in terms of legibility and comfort of reading, and to optimize the overall homogeneity of the cockpit.
2 years later, Airbus came to find Intactile DESIGN to work on the design of the eight typographic variants of the font. This one, baptized B612 in reference to the imaginary asteroid of the aviator Saint‑Exupéry, benefited from a complete hinting on all the characters.
See page 11 of leaflet.pdf about comparison between characters fo differents fonts from Humanist to Technical.
B612-Bold.ttf B612-BoldItalic.ttf B612-Italic.ttf B612-Regular.ttf B612Mono-Bold.ttf B612Mono-BoldItalic.ttf B612Mono-Italic.ttf B612Mono-Regular.ttf
Copyright (c) 2012, AIRBUS (airbus-group.com). All rights reserved. License : SIL Open Font License v1.1 - https://scripts.sil.org/OFL
Humanstist 521 Light Copyright (C) Bitstream 1990-1993
Related license unknown to our knowledge. Humanist 521 fonts are available for free on many fonts web sites. We saw Monotype has acquired Bitstream and we've got serious reasons to believe Humanist 521 Light font falls into commercial license rules. When in doubt, and assuming that the Humanist font was a thing of the past (no € and ¢ signs for example), we found the very legible B612 font above to be relevant.