The de Havilland DH.42 Dormouse and its two variants the de Havilland DH.42A Dingo I and II were two-seat single-engined biplanes designed for fighter-reconnaissance and army cooperation roles. They did not achieve production.

The Armstrong Siddeley Jaguar is an aircraft engine developed by Armstrong Siddeley. The Jaguar was a petrol-fuelled air-cooled 14-cylinder two-row radial engine design. The Jaguar III was first used in 1923, followed in 1925 by the Jaguar IV and in 1927 by the Jaguar VI. In 1925 the Jaguar became the first production aero engine incorporating a geared supercharger.