I have a route wit about 900 miles of track. One 200 mile section has a speed limit problem. The section is posted with 55mph signs. At the first sign the speed indication (bottom of screen) shows the limit going to 55mph/25mph. The train proceeds pas multiple 55mph sign with no change - stuck at 25 mph ???????. All signals are erased so that source of limitation is gone as are all "dummy" signals used to suppress the 1/2 speed limit of certain signals. The limited speed continues until the destination at end of track. ???
False Speedlimit?
- Thread starter boleyd
- Start date
I suspect that you have found and stated the cause of your problem.
There is a limit to how far an AI train will "look ahead" to find the next signal. I do recall reading somewhere what that distance is but I cannot recall it. In any case it was a great deal less than 200 miles.
If the AI sees no signal in that distance it will drop to half speed.
I am assuming that in the 200 mile stretch there will be turnouts, junctions, etc. This is where signals, visible or invisible, should be placed.
In my current project I have a 90km single line branch that has no signals, both in real life and in my model. To prevent this half-speed problem I have invisible signals at the approach to each location (turnouts, sidings, passing loops, etc) along the line. These locations are about 10kms apart and all had the half-speed problem without the invisible signals - so I guess that the "look ahead" distance is less than 10kms.
Last edited:
norfolksouthern37
what's a normal map?
no object on the track can 'see' more than 32 km.
You are correct. My logic was wrong. If placing signals about 10km apart solves the half speed problem then the "look ahead" distance is AT LEAST 10km, not less than 10km.
The route is a coastline with three branches. Only one branch seems to require signals. The other two work ok with NO signals. The main coastal line that feed the branches also does not require signals. Ran trains with no slow-downs on any of them. So, pending further tests, it looks like only one branch needs signaling. Will do more tests. The route is a modification of the MSGSAPPER Maine Coastline route.
Check your switches. If the switches are set against the driver, the driver will operate at half speed because the AI driver "sees" the upcoming junction set against the route, therefore, operates under caution. To get around this, place some advance or permissive signals inbetween the the beginning and end of the branch. These are type 05 signals by Jointed Rail and have small black panels underneath that would normally have a signal number which you can enter if you want. The purpose of the signal name/number is for the driver to normally call into the dispatcher and ask for permission, thus the permissive, aspect of the signals.