Editing Special Operations Executive (section)

====Locating and homing equipment====
Some devices used by SOE were designed specifically to guide aircraft to landing strips and dropping zones. Such sites could be marked by an agent on the ground with bonfires or bicycle lamps, but this required good visibility, as the pilot or navigator of a plane had not only to spot the ground signals, but also to navigate by visible landmarks to correct dead reckoning. Many landings or drops were thwarted by bad weather. To overcome these problems, SOE and Allied airborne forces used the Rebecca/Eureka transponding radar, which enabled a Hudson or larger aircraft to home in on a point on the ground even in thick weather. It was however difficult for agents or resistance fighters to carry or conceal the ground-based "Eureka" transponder equipment.

SOE also developed the [[S-Phone]], which allowed a pilot or radio operator aboard an aircraft to communicate by voice with the "reception committee". Sound quality was good enough for voices to be recognisable, so that a mission could be aborted in case of any doubts of an agent's identity.{{Sfn|Foot|2004|pp=103–104}}