But I read somewhere that the the color of the flights were: 1st flight has White serial numbers, 2nd flight - Green, 3rd flight - Red and Staff flight - Yellow.
Stoyan Stoyanov was a member of 3.6 Orlyak, so the number should be "red 1". Like this illustration:
View attachment 366652
Does anyone can confirm or not the color of the flights in Bulgarian Air Force during WW2 please ? TIA
Steph