3 decal variants:
1. De Schelde S-21, prototype
2. De Schelde S-21, MAy 1940
3. Focke-wulf Fw-198, De Schelde renamed by Luftwaffe
Designed by TE Slot for the Dutch firm De Schelde, the S.21 was a single seat fighter which reached the advanced prototype stage. Construction commenced early in 1939. Aspects that deviated from these designs included an extensively glazed cockpit and a semi-reclined seat for the pilot.