Circus offensive

[2] There would be two types of offensive operation: "Rhubarb" (initially called Mosquito), in which small patrols would cross under cover of cloudy conditions and engage any aircraft they found; and on clear weather days "Circus", in which several squadrons - possibly with a few bombers - would conduct sweeps of northern France.

By mid-June 1941, Fighter Command had flown 149 Rhubarb patrols (336 sorties) claiming seven enemy aircraft brought down for loss of eight pilots on the British side.

Circus operations with bombers began in January and eleven had been carried out by June, the targets including docks on the French coast and airfields.

[1] The Air Ministry directed the RAF that the purpose of Circuses would be destruction of the ground targets with German fighters as secondary priority.

[3] Included in the lost RAF aircrew, killed or captured, were some of their most experienced officers; thirty flight lieutenants, twenty squadron leaders, six wing commanders and one group captain.

Additionally the German commanders were free to choose which raids to challenge and which to ignore, since the bomber forces deployed by the RAF were rarely large enough to inflict critical damage.

[6] Besides the poor loss ratio of more than two British aircraft to one German, another stated aim of the campaign from the summer of 1941 was to divert Luftwaffe air assets away from Operation Barbarossa, the Axis invasion of the Soviet Union.

The situation was worse in the Far East, where the RAF had to meet the Japanese invasion of Malaya equipped with the obsolescent Brewster Buffalo, an American fighter deemed unfit for service in Europe.