I realize that. The OP's goal was to find interesting or significant military aircraft from the early 1930's that were mostly out of service by WWII. This is somewhat contradictory, as a well designed aircraft from this period should make it into WWII.OP ruled out I-16 in first post.
Thank you, great find!!Here's an interesting web site with lots and lots of airplanes that did and didn't participate in the Spanish Civil war:
Seems like a list of aircraft from that period that don't appear here would be shorter than the list of those that do. ;-)
I think the P-26 was operated by a couple of squadrons in the Philippines Army Air Corps (not USAAF) and by the Chinese; the I-16 was served in large numbers against the Luftwaffe. (although you may accuse me of being inconsistent, if you choose)It's not on the list, but I would vote for the Polikarpov I-16 as the most significant inter-war era fighter.
The first all metal, cantilever low wing monoplane, retractable landing gear fighter.
View attachment 59153View attachment 59154
It did make it into WWII, but so did the Peashoter.