OK, I need a clarification on the mentioned subject. For example if MAS is 15 MPH and ATC is showing 40 MPH which speed should I use? I suppose lower one which is 15 MPH. Why then ATC is not showing 15 MPH as well? If I go 40 MPH I will get minus AP for driving above speed limit o_O. This is just one of many situations. Except Atlantic terminal where 5 MPH is the limit what is understandable because ATC can not go below 15. I read carefully guides and I know ATC can show different values but it should not be above MAS shouldn't be? Thanks in advance. Cheers!
You should be driving the lower one, but in fairness there are parts where ATC and the speed limits in LIRR are kinda broken.
The thing to remember is that the ATC has no idea of the track speed limits, it only gets fed information on the signal status. Therefore there can be a variance as mentioned, the lower limit always applies.
As far as I know, ATC takes info from the "code change points". "The wayside signal equipment injects pulse codes into the rails at various rates. These rates (expressed in pulses per minute) are indicative of certain signal aspects" (thank you CactusJuice for your signal guide). Why not to use code change point at the route speed place to determine MAS same, especially when signal aspects change and the MAS on the route not?
