A British railway term for the mechanical or electronic cab indicator tied to the Automatic Warning System. When an engineer acknowledges a restrictive signal, the device displays a black-and-yellow segmented circle resembling a sunflower. It serves as a persistent visual reminder that the train is operating under a restrictive block.
Heard on the job
The horn sounded for the yellow aspect, and as soon as I hit the button, the sunflower popped up on the dash.
Insider tip
North American crews use alerters and cab signals instead of the British AWS system, so this term is rarely heard on US or Canadian rails.