5 decal variants:
1. Bücker 131A, FFS A/B 72, Schwerin/Göriss, Luftwaffe 1944
2. Bücker 131A, "Kör Ász" /Red Hearts/ Squadron, Royal Hungarian Air Force, 1941
3. Bücker 131A, Spanish A.F., 1937
4. Tatra T-131, Slovenský letecký sbor, Slovakia 1940
5. Bücker 131A, Liesel Bach, Bücker Factory Aircraft, Germany 1936
First aircraft were delivered to the Luftwaffe in 1935 year. During 1936, was produced Bü 131B with powerful 105hp Hirth HM 504A-2 engine. Most produced was the version D. The aircraft was used by Luftwaffe as training, also by night ground-attack. Was also exported in many countries - Japan, Switzerland, Spain, Yugoslavia, Romania and Bulgaria. Under licence was built in Japan and after WWII also in Spain-CASA and Czechoslovakia as C-104 trainer with Walter Minor 4-III.