Speed Problem In Tunnel

[Ian_Coleman]

I am using TRS2004

I have a layout where a track enters a tunnel and loops round so that it emerges alongside its entry point. I am using this as a method of turning a train round for a return journey.

When an AI train enters the tunnel the speed of the train, which is set at 80mph, drops down to 9mph.

I sent a loco without a consist through the tunnel and it kept to its alotted speed with no problem, but as soon as I attach a few carriages, the speed returns to 9mph.

Would the speed be dropping to 9mph because the circumference of the loop is too small, or is there perhaps another reason?

Ian

 

[Ferrous]

Hmm....maybe you need more signals? Try placing a few signals on the route, if it's a closed loop, and see what happens. :wave:

 

[Approach_Medium]

What's the grade inside the tunnel? You haven't somehow forgotten to check, and have a really steep grade, do you?

FW

 

[Ian_Coleman]

Nope! There's no grade.

I have a double track from a terminus leading to a 2-platform station.

Beyond the station (platform 1) the track loops round inside the tunnel, and emerges as platform 2, continuing back to the terminus.

I have a signal at the inward end, immediately before the tunnel, and the next signal is at the end of platform 2.

I hope that makes things clearer.

 

[Captain_Collins]

Nope! There's no grade.

I have a double track from a terminus leading to a 2-platform station.

Beyond the station (platform 1) the track loops round inside the tunnel, and emerges as platform 2, continuing back to the terminus.

I have a signal at the inward end, immediately before the tunnel, and the next signal is at the end of platform 2.

I hope that makes things clearer.

Try a signal right before platform 2. It could be an AI bug.

 

[Ian_Coleman]

Problem Solved!

I tried the signal just before platform 2 but it didn't make any difference.

However, I have now solved the problem by placing a trackmark half way round the tunnel and giving the AI instruction to drive via that trackmark.

I'm pleased to say that the train now zooms round the tunnel at 60+ miles per hour!

Ian