(1936) 205 hp (153 kW), military version of Gipsy Six II. Splined crankshaft, but intended for fix-pitch airscrews fitted with an adapter. No fittings for a VP airscrew fitted. Very limited production.
Gipsy Queen II
(1936) 210 hp (160 kW), military version of the Gipsy Six Series II. Strengthened crankcase. Splined crankshaft for V/P airscrew.
Gipsy Queen III
(1940) 200 hp (150 kW), military version of Gipsy Six, strengthened crankcase, tapered crankshaft for fixed-pitch;-1,358 built. Most of these engines were fitted with a very basic top-cover, as per the early Gipsy-Six, with no accessory drives at the rear of the top-cover whatsoever.
Gipsy Queen IV
(1941) Supercharged version, originally designated Gipsy Queen IIIS, designated Gipsy Queen 50 in June 1944. Only a handful were made. This engine was widely advertised at the time, however, it never entered production, as it was superseded by the completely re-engineered Queen 30.