Thanks Pisis, it's an interesting aircraft, that's for sure. It looks so much like the G.1. Even the Czech roundels look like the Dutch ones.
What does 'Tento prototyp ještě létal s třídílným křídlem a střeleckou věží na zádi trupu.' mean? Google translation makes a mess of that one. And what does 'jako třepetání ocasních ploch' mean? Vibrating tail?