Messerschmitt Bf 109 Bf 109 A

The Bf 109 A was the first version of the fighter, a direct descendant of the V4 prototype. The first A-0s were powered by the 471 kW (631 hp) Junkers Jumo 210B engine driving a two-blade fixed-pitch propeller; production switched to the 493 kW (661 hp) Jumo 210D as soon as it became available. It was not a uniform type: there were visible changes to the engine, the cockpit and gun ventilation slats, and the position of the oil cooler, which was relocated several times to prevent overheating. Many A-0s served with the Legion Condor during the Spanish Civil War, where they were often misidentified as B-series aircraft, carrying tactical markings 6-1 to 6-16. One of them, 6-15, ran out of fuel and landed behind Republican lines on 11 November 1937; it was captured and transferred to the Soviet Union for inspection, and already incorporated several improvements from the Bf 109 B production programme, plus provision (though not fitted) for a variable-pitch propeller. According to RLM documentation, 22 aircraft were delivered with the V4 as the A-series prototype.