if atc_arrow then
    atc_send("SM")
    set_line("21")
    atc_set_text_outside("Line 21\n---> Turtle Rock")
    atc_set_text_inside("Next stop: Clown Island")
else
    atc_send("B1")
    set_line("X")
    atc_set_text_outside("NOT IN SERVICE")
    atc_set_text_inside("DEPOT")
end