It was first flown by de Havilland on 4 December 1911. The aircraft was not flown again until 27 December, modified by the substitution of a Claudel carburettor in place of the original Wolseley, which allowed no throttle control. Other minor modifications were made over the following weeks: the undercarriage wheels were moved back 12 in (30.4 cm), the wings (which originally had no dihedral), were re-rigged to have 1° dihedral, and the propeller was cut down in an attempt to increase the engine speed. Later, the Wolseley engine was replaced by a 60 hp (45 kW) air-cooled Renault.