On Thursday, January 23, 2020 at 8:39:31 AM UTC-5, Jim Hogue wrote:

I take care of navigation and tasks with other standalone devices (full on OpenVario with its own vario/STF sensor board

From the translation of Air Avionics statement:

AIR Avionics wants to support interested parties and the open source community, gain further knowledge and software components.

One can dream that the Butterfly tech will find its way into Open Vario eventually.