The Focke-Wulf Fw 159 was an experimental German fighter aircraft of the 1930s that never reached production. The Focke-Wulf company designed the aircraft as one of the four entries for the “Armed Aircraft IV” (Rüstungsflugzeug IV) 1934 fighter competition. Its parasol wing configuration was based on the company's successful trainer product, the Focke-Wulf Fw 56 "Stösser" and it used a Junkers Jumo 210 engine. The plane had a retractable undercarriage and an enclosed cockpit, although the undercarriage mechanism was very complicated proved troublesome.

The first prototype, FW-159 V-1 was ready in the spring of 1935, but was destroyed when it crash landed following the failure of the undercarriage to deploy properly.

The second prototype V-2 had reinforced undercarriage. The flight characteristics were good but the rate of climb and rate of turn was unsatisfactory, and the aircraft suffered greater drag than its competitors in the contest (which were Arado Ar 80, the Heinkel He 112 and the Messerschmitt Bf 109). The competition was won by the Messerschmitt Bf 109.

Sources:
Gunston, Bill & Wood, Tony - Hitler's Luftwaffe, 1977, Salamander Books Ltd., London