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Summary
DescriptionWorld War II RAF sector clock.jpg
English: A timestamp indicator clock from the Second World War on display at the Science Museum, London. A large horizontal map was at the heart of the RAF Fighter Commandcontrol room. Enemy aircraft were tracked by placing markers on the map. These markers were colour-coded according to when they were first sighted (mainly by the Royal Observer Corps. The red, yellow and blue triangles on the clock identified the colour to be used.
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