megan The Stuka pic above still intrigues a bit. The Slovak Air Force used the cross with a red dot (not visible) in between 1941-1944/5, not before. At the time the registration was S.
OK was first introduced in 1930 for the civilian aeroplanes of Czechoslovakia, replacing the "L". Post-war the Czechoslovak air force planes had no country registration letters at all, it seems. Only painted insignia.
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and found it!
https://ww2aircraft.net/forum/thread...vice-gb.30903/
The "Take-off" monthly magazine of the SAF 06-07/1944 - article on the pre-flight inspection and engine run-up. First airframe delivered to customer 1.6.1944
