In 1932 Fokker discussed some ideas with his Technical Department for an aircraft with a fuselage of oval crosssection instead of the traditional rectangular one.

The availability of increasingly more powerful engines meant that aircraft could reach higher speeds. it also meant that there was a greater need to streamline the airframe. Subsequent research led to a design designated the F.XXI which had the same capacity as and comparable dimensions to the Fokker F.VIIb-3m.

It was clearly intended as a successor to this earlier aircraft of which many had been built. At its widest point, the eliptical fuselage measured the same width as the F.VIIb-3m.

The distance between the cabin floor and the ceiling was slightly over 6 ft, so that most passengers could stand upright. Baggage space was available aft of the cabin, and there were also two cargo holds in the wing. Initially the F.XXI was to be equipped with two engines mounted in the wing leading edge.

Later this was changed to a three-engined arrangement. Fokker brochures on the F.XXI were fulsome in describing the many advantages of the new aircraft over the F.VIIb-3m, but airlines did not seem to be impressed.

The F.XXI was technically an interesting step forward, but it failed to enter production.

It was perhaps another victim of the prevailing economic depression.