It's very simple NEVER cross a red stopbar unless specifically instructed by ATC. The amount of times crews cross a red stop-bar when given a line-up instruction and the controller does not inmediately drops the stop-bar is shocking. If you are given a line-up instruction and the stop bar stays illuminated question the stop-bar. There could be a fault with it that we ATC don't know about. If we drop it and it stays on and a plane crosses it, how are we suppossed to know the thing is broken?
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