From 1941 onwards, No. 138 and No. 161 Royal Air Force Squadrons were reformed as Special Duties Squadrons and deployed on hundreds of missions under the guidance of the Special Operations Executive. This was a top secret government organization involved in espionage operations all across occupied Europe. Overseeing a large network of spies and partisans, the Special Operations Executive required the services of the Special Duties Squadrons to drop and lift spies and supplies into and out of occupied territories. Covert sorties were launched from the main Special Duties airfield RAF Tempsford, along with other British airfields and numerous airfields in Italy later in the war. Various long-range bomber aircraft were used for airdrops, however the Westland Lysander was the specialist aircraft used in drop-off and pick-up missions, where its short runway requirements made it ideal for missions in which field agents needed to be lifted from enemy territory.
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