HS-123 Wooden airplane model. Designed to an official requirement for a dive-bomber, issued in 1933, the Henschel Hs 123 single-bay biplane was of all-metal construction, with fabric covering used only for the rear portions of the wings and the control surfaces. Powered by a 650 hp (485 kW) BMW 132A-3 radial engine, the prototype flew in 1938 and quickly established its superiority over the rival Fieseler Fi 98. The third prototype was the first to be armed, carrying two fixed forward-firing 7.92 mm (0.31 in) MG 17 machine-guns in the fuselage top decking. The first three aircraft were flown to Rechlin for testing in August 1935, in the course of which activity two of them were destroyed when their wings came off in dives. A fourth prototype tested successfully the structural changes introduced to overcome this problem and initial production orders were placed for the Hs 123A-1, which retained the blistered cowling of the second and third prototypes, rather than the NACA cowling of the first. Power was provided by the BMW 132De radial engine and, in addition to the two fixed MG 17 machine-guns, a mounting for a 551 lbs (250 kg) bomb or an external fuel tank was included beneath the fuselage, and four 110 lbs (50 kg) bombs could be carried on underwing racks. The Hs 123 was built at Henschel's Schonefeld and Johannisthal factories in Berlin, but although the company built two prototypes, the first, an improved Hs 123B version with the 960 hp (716 kW) BMW 132K engine, the second, designated Hs 123C, differed by having two additional MG 17 machine-guns and an enclosed cockpit for use as an intended ground attack aircraft, the Luftwaffe expressed its satisfaction with the Junkers Ju 87 and production ended. The Hs 123A first entered service with 1./StG 162 in the autumn of 1936, although its career as a front-line dive-bomber was short-lived because the Junkers Ju 87A Stuka began to replace it in 1937. Five Hs 123As were supplied to the Legion Condor in Spain in December 1936, the type also saw operational service as a close support aircraft in Poland during the closing months of 1939 and in the campaigns in France and Belgium during the spring of 1940. It was withdrawn finally in 1944.