Question: Focke-Wulf Fw 187 was an intermediate design above the model that was the backbone of which fighting force?

Context paragraphs:
Focke-Wulf 1000x1000x1000: The Focke-Wulf 1000x1000x1000, also known as Focke-Wulf Fw 239, was a twin-jet bomber project for the Luftwaffe, designed by the Focke-Wulf aircraft manufacturing company during the last years of the Third Reich.

Focke-Wulf Fw 200 Condor: The Focke-Wulf Fw 200 "Condor", also known as "Kurier" to the Allies, was a German all-metal four-engined monoplane originally developed by Focke-Wulf as a long-range airliner.  A Japanese request for a long-range maritime patrol aircraft led to military versions that saw service with the "Luftwaffe" as long-range reconnaissance and anti-shipping/maritime patrol bomber aircraft.  The Luftwaffe also made extensive use of the Fw 200 as a transport.

Focke-Wulf Fw 260: The Focke-Wulf Fw 260 Flamingo and Focke-Wulf Fw 300 were a pair of related VTOL airliner projects, designed by Focke-Wulf during the early 1960s.  Neither aircraft was built.

Focke-Wulf Fw 187: The Focke-Wulf Fw 187 "Falke" ("falcon") was a German aircraft developed in the late 1930s.  It was conceived by Kurt Tank as a twin-engine, high-performance fighter, but the "Luftwaffe" saw no role for the design, perceiving it as intermediate between the Messerschmitt Bf 109 and Bf 110.  Later prototypes were adapted to two-seats to compete with the Bf 110 in the "Zerstörer" (heavy fighter) role, but only nine aircraft were built in total.

Messerschmitt Bf 109: The Messerschmitt Bf 109 is a German World War II fighter aircraft that was the backbone of the Luftwaffe's fighter force.  The Bf 109 first saw operational service in 1937 during the Spanish Civil War and was still in service at the dawn of the jet age at the end of World War II in 1945.  It was one of the most advanced fighters of the era, including such features as all-metal monocoque construction, a closed canopy, and retractable landing gear.  It was powered by a liquid-cooled, inverted-V12 aero engine.

Focke-Wulf Fw 159: The Focke-Wulf Fw 159 was an experimental German fighter of the 1930s, designed by Kurt Tank which never reached production, as it was considered inferior to the He 112 and Bf 109.  It was a heavier variant of the Focke-Wulf Fw 56, with several improvements, such as a retractable landing gear and enclosed cockpit.

Focke-Wulf Fw 186: The Focke-Wulf Fw 186 was a one-man autogyro, built by Focke-Wulf in 1937 with backing from the RLM ("ReichsLuftfahrtMinisterium" - Reich Aviation Ministry), for use as a liaison and reconnaissance aircraft.  It featured short takeoff and landing (STOL) characteristics.  However, only one prototype of the aircraft was constructed, and the project was abandoned when the RLM preferred the Fieseler Fi 156 Storch over the Fw 186.

Focke-Wulf Fw 190: The Focke-Wulf Fw 190 "Würger" (English: Shrike ) is a German single-seat, single-engine fighter aircraft designed by Kurt Tank in the late 1930s and widely used during World War II.  Along with its well-known counterpart, the Messerschmitt Bf 109, the Focke-Wulf 190 Würger became the backbone of the Luftwaffe's "Jagdwaffe" (Fighter Force).  The twin-row BMW 801 radial engine that powered most operational versions enabled the Fw 190 to lift larger loads than the Bf 109, allowing its use as a day fighter, fighter-bomber, ground-attack aircraft and, to a lesser degree, night fighter.

Focke-Wulf Fw 42: The Focke-Wulf Fw 42 was a design for a twin-engined medium bomber, of canard configuration, that was designed by Focke-Wulf Flugzeugbau AG in Germany in the early 1930s.  Several air forces expressed interest in the aircraft.  However, despite its advanced design being proven sound in wind tunnel testing, the Fw 42 failed to win a contract for development, and no examples of the type were ever built.

Focke-Wulf Fw 300: The Focke-Wulf Fw 300 was a proposed very-long-range civil airliner, transport, reconnaissance aircraft and anti-ship aircraft, designed by Focke-Wulf in 1941 and 1942.  The design was intended to replace the Focke-Wulf Fw 200 "Condor".

Supporting paragraphs: Focke-Wulf Fw 187 Messerschmitt Bf 109
Answer: Luftwaffe