What nationality are these pilots? Croatia?

[Theodor]

Hi,

I got many pictures today, including this one. The Bulgarians, that's clear... But what are the others? I think they are Croatian, aren't they? Or Yugoslavian?

[Theodor]

closer

[Theodor]

...also, any ideas about the man in the middle of the picture? From which country is he? What indicate the stripes on the sleeves?

[Rolf D.]

Given the company I'd have to agree with Tod Rathbone and say that they are Balkan.

[JBFloyd]

The folks in the group photo seem to be wearing Yugoslavian flight badges and their cap badges also have the royal Yugoslavian crown. A couple are wearing Yugoslavian Order of the Crown insignia.