The Dewoitine company went bankrupt in January 1927 and Émile Dewoitine temporarily moved to Switzerland where EKW continued development of the new D.27 fighter. Ten D.21s ordered by Argentina and Czechoslovakia were also built by the Swiss state factory, the D.21 being a variant of the D.1. This airframe was destined for the Argentine navy as the anchor marking makes clear. Photo from: ETH-Bibliothek Zürich

First flown in November 1922, the D.1 was a modern fighter built largely of metal. The fabric-covered wing was originally mounted on the fuselage but raised on the D.1bis and ter to improve the visability for the pilot. Main customers were Italy, where a smaller variant was built as the Ansaldo AC.2, Yugoslavia and the French navy. Two D.1s, including this one, were delivered to Switzerland. C1 on the tailfin is a French code for a single-engined fighter. Photo from: ETH-Bibliothek Zürich