In 1937 Focke-Wulf flew a fighter that was roughly 80 km/h faster than the Messerschmitt Bf 109 then in service, using exactly the same engines. It had twice the range. It weighed twice as much and still outran the thing it was compared against.

Nine were built. The Luftwaffe never ordered any, and the handful that existed spent the war defending the factory that made them.

The Fw 187 Falke is one of the most argued-about aircraft in German aviation history, partly because it was good, and mostly because the surviving paperwork contradicts itself.

A long-range fighter nobody had asked for

Kurt Tank began the design as a private venture in early 1935, with detail work by Oberingenieur Rudolf Blaser. The intent matters: Tank wanted a single-seat long-range fighter. He explicitly did not want a Zerstörer, the heavy twin-engine destroyer concept the ministry was interested in.

The V1 flew in the spring of 1937. English and German accounts disagree on the specifics, one giving a late-spring flight with Hans Sander at the controls, the other 10 April with Tank himself flying, and they even disagree on the registration. It is not a detail worth pretending to be certain about.

The speed claims need the same care. The widely repeated figure has the V1 at 523 to 525 km/h, some 80 km/h faster than the Jumo-powered Bf 109B. But an apparent official ministry table quoted by the engineer Hermann Kosin gives the V1 only 457 km/h at sea level and 496 km/h at 4,000 m, which would make the margin closer to 35 km/h. The V2 at the Rechlin test centre returned 501 km/h at 3,000 m. Researchers who have gone back to the monograph literature suggest the famous 525 figure came from an interview with Hans Sander and referred to low level, not altitude.

Even at the conservative end, a twin with twice the fuel and twice the weight matching a contemporary single-seat fighter on the same engines is a remarkable piece of aerodynamics.

The 635 km/h that was not a record

One prototype was re-engined with Daimler-Benz powerplants and an experimental surface-evaporative cooling system, and in October 1939 flight trials produced 635 km/h. That number gets quoted constantly, usually without its conditions.

The German original specifies in Bodennähe, close to the ground. It was achieved on non-standard prototype engines with a cooling system that never worked properly and was abandoned by February 1942. It was never an officially recognised record; the aircraft intended to attempt one was never built. The same authors estimate a hypothetical production machine with normal radiators would have managed around 620 km/h at 5,000 m.

There is even a dispute about which airframe it was. The standard English sources say the V6 carried the Daimler-Benz engines. The German archive-based monograph, working from Focke-Wulf and Daimler-Benz documents, says it was the V5, backed by a cost file listing that airframe with DB 601s. The two accounts are frequently blended into a third version that no source actually supports.

Why the ministry said no

The doctrinal answer is the one usually given, and it is largely right. In the late 1930s the Luftwaffe believed in the Schnellbomber: a bomber fast enough to outrun interceptors would not need a fighter escort, so a long-range escort fighter had no mission to fly.

There was also a practical objection that the design never really answered. From the third prototype the fuselage was stretched and a second crewman added, but he was a radio operator only. The high fuselage line left no room for a rear-facing defensive gun, so the aircraft carried the weight and drag of a second man without gaining the defensive firepower that justified a two-seat heavy fighter.

Guarding the factory

The three A-0 aircraft ended up with the Werkschutzstaffel at Bremen, the flight tasked with defending Focke-Wulf's own works against air attack. That is the entirety of the type's operational career.

Attempts to revive it went nowhere. A development meeting in August 1942 recorded that restarting the programme would in practice mean an entirely new aircraft, since little beyond the external shape of the old Fw 187 would remain. The night-fighter role it might have filled went to the Heinkel He 219 instead, and the German monograph on the type is candid that no official reason for that decision has been found in the records.

The Falke has become a favourite of the what-if literature, and some of the enthusiasm is overdone. Its best-known speed figure was measured at low level on engines it never carried in service, and the Bf 109E of 1940 had closed most of the gap anyway.

But the underlying point stands. In 1937 Kurt Tank built a twin-engine fighter that flew as fast as the single-seaters on the same engines and could go twice as far, and the air force that would spend 1940 discovering it had no escort fighter for the Battle of Britain had already decided it did not need one.

Sources: Focke-Wulf Fw 187 entries, English and German Wikipedia; Dietmar Hermann and Peter Petrick, Focke-Wulf Fw 187 (2001/2003); Heinz Conradis, Design for Flight: The Kurt Tank Story (1960); Hermann Kosin on RLM performance tables; Dan Sharp, Secret Projects Forum, May 2021; historyofwar.org. Where sources conflict, both readings are given above.