Enemy aircraft approaching Britain were picked up by the radar until they crossed the coast. Then they became the responsibility of the Royal Observer Corps. Radar could only pick up enemy aircraft over the sea. It didn’t operate over land. There, it had to be the job of human eyes and a system linked to that. The Observer Corps consisted of a large number of personnel dotted around the countryside. Each post consisted of three essential positions, one using binoculars to watch, a second to operate the log and the third reporting what had been observed to the Observer Corps Headquarters in Horsham. Most of those involved were middle aged but there were also one or two youngsters on the post making themselves useful and in particular making the tea.

The Observer Corps played a vital part in the Battle. It was manned entirely by volunteers who were drawn to their task by patriotism and comradeship. There were some 30,000 during the Battle, including 4,000 women. They were the RAF equivalent of Captain Mainwaring and his faithful platoon. The Observer Corps obtained its title of “Royal” in 1941 in response to official recognition of the valuable part it had played in the Battle.

The Observer Corps relied on a key figure in their midst to enable them to perform their job efficiently, he was the “Aircraft Recognition Expert” who taught them to recognise the silhouettes of the aircraft they were observing. The silhouettes were on cards. The experts used an epidiascope which, with a small screen, was set up to rehearse the men with the binoculars in the art of aircraft recognition. He trained them to tell which aircraft was which. He was particularly keen to get them to recognise the difference between Spitfires, Hurricanes and Me109s. It was all part of increasing their effectiveness.