In a message dated 25/05/2007 19:31:32 GMT Daylight Time, gwinsk@xxxxxxx writes: Probably, though the 80 is really just a wake up call. The trick is how to get it to send signals when the aircraft has reached the Vspeed currently calculated V1 and Vref. Gerry Winskill If e.g V1 is known, is it not a case of - IF Groundspeed < V1 then (graphic 1) else (graphic 2) Frank T.