The PZL-37A / B Łoś is a Polish, two-engine low-wing bomber with a full metal structure, with a retractable landing gear. The flight of the prototype took place in December 1936, and serial production continued in 1937-1939. The PZL-37 was the most modern Polish military aircraft built before World War II and the world's first serial aircraft with a laminar wing profile. As a result, it developed a speed in excess of 400 km / h. The plane was among the world's top bombers at the end of the 1930s. By September 1939, 96 Elks had been built, 9 of which were crushed. 40 fought in the Bomb Brigade, while 37 were in the training squadron and in the Aviation Cadet School, and 5 in trials and 5 in repairs. The elk of the Bomb Brigade was fought by the German armored units near Radomsko, Pułtusk and Różan. 23 Łosie were evacuated to Romania, 2 landed in the USSR, 2 were captured by the Germans, and 60 were destroyed. The Romanian air force commandeered Łosie. Romanian characters and numbers from 201 to 220 were painted on them. They were used by Romania, which fought on the side of Germany with the Soviet Union, among others for the bombing of Odessa. Technical data (version B): length: 12.92 m, wingspan: 17.93 m, height: 4.25 m, maximum speed: 412 km / h, practical ceiling: 9250 m, maximum range: 1500 km, armament: fixed - 3 machine guns wz.37 7.92mm caliber, suspended - up to 2580 kg of bombs.