A little more.
Robert Nebasář, the Avia's designer worked on the metal fuselage Lockheed Vega DL-1 (Y1C-12) at Detroit Aircraft before returning to Prague and joining Avia.
This nice salon photo is from my copy of Revolution In The Sky by Richard S. Allen (1964).
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WOW! That is an amazing find! This picture shows some detail I hadn't previously seen.
Thanks you so much for your efforts Sir.
Just to let you know, I am working on this diligently (like 10 hours a day) while waiting for other progress on the Grumman project, and I do appreciate all the help.