Defence of Great Britain against air attack: Handbook for plotters at an observer centre

At the start of the Second World War the UK had a highly developed air defence network which was dependent on information gathering and dissemination. Providing commanders with timely intelligence with which to make decisions and deploy their forces accordingly.

The Observer Corps was an integral part of the system. Radar was still in its infancy and was only able to detect aircraft flying at medium to high level over sea, once over land the aircraft could not be tracked by radar and a network of observer posts, manned largely by volunteers tracked enemy raids over land. Observer Posts sent their information to an Observer Centre which plotted the information from numerous posts. The compiled air picture was then passed to Fighter Command HQ , Group and Sector HQs providing commanders with as much available information to support effective decision-making. This pamphlet describes the role of a plotter at an Observer Centre.