The Henschel Hs 123 was a successful single-seat biplane used for dive bombing and close air support by the German Luftwaffe in the Spanish Civil War and early WWII. It was known for being tough and effective even in harsh conditions. The Hs 123 remained in service until 1944, but it was eventually retired because there were no longer enough usable planes or parts to keep them flying (production had stopped in 1938).