propulsion power of bidirectional trains

[Koub]

[Koub] Merged into older topic with same suggestion.

[Vegemeister]

Bump, so as not to just be urgin' for a mergin'.

The way it is now, there's practically no reason to ever use bidirectional trains. Their only advantage over single-headed trains is that you save a little space around stations and don't have to use underground belts to cross the exit tracks. Without even mentioning the non-contributing locomotives, the disadvantages are many:

1. Lower maximum throughput, since a train has to back completely out of the station platform before the next train can enter. 1-way trains can use RORO stations with mid-platform signals.
2. 2-way trains that have an odd number of terminus stations on their schedule will reverse every other cycle, and must be palindromic.
3. Require signalling of bidirectional track, which is more difficult to wrap your brain around than 1-way track. (If you know how to drive a car, once you learn chain signals mean "can't stop in here", you know everything you need to signal 1-way track.)

But on top of that, the compounding effect of non-contributing locomotives makes 2-way trains much larger and slower than their 1-way brethren. 1-4 trains are widely regarded as having a somewhat poor power-to-weight ratio. The intersection comparison testing thread uses 2-4 as their standard. But if you want a 4-wagon, 2-way train train that matches the acceleration performance of a 1-4, you need a 2-4-2. That's 60% longer and 4x as many locomotives.

For the purpose of offsetting the single advantage of 2-way trains, I think the throughput and complexity penalties of terminus stations are enough. Backwards-facing locomotives should contribute 100% power in automatic mode.

[mrvn]

Bump, so as not to just be urgin' for a mergin'.

The way it is now, there's practically no reason to ever use bidirectional trains. Their only advantage over single-headed trains is that you save a little space around stations and don't have to use underground belts to cross the exit tracks. Without even mentioning the non-contributing locomotives, the disadvantages are many:

1. Lower maximum throughput, since a train has to back completely out of the station platform before the next train can enter. 1-way trains can use RORO stations with mid-platform signals.
2. 2-way trains that have an odd number of terminus stations on their schedule will reverse every other cycle, and must be palindromic.
3. Require signalling of bidirectional track, which is more difficult to wrap your brain around than 1-way track. (If you know how to drive a car, once you learn chain signals mean "can't stop in here", you know everything you need to signal 1-way track.)

But on top of that, the compounding effect of non-contributing locomotives makes 2-way trains much larger and slower than their 1-way brethren. 1-4 trains are widely regarded as having a somewhat poor power-to-weight ratio. The intersection comparison testing thread uses 2-4 as their standard. But if you want a 4-wagon, 2-way train train that matches the acceleration performance of a 1-4, you need a 2-4-2. That's 60% longer and 4x as many locomotives.

For the purpose of offsetting the single advantage of 2-way trains, I think the throughput and complexity penalties of terminus stations are enough. Backwards-facing locomotives should contribute 100% power in automatic mode.

You can use terminal stations with one way tracks just fine and that's actually the most useful way I think. Build a large loop for your rail system. Then add terminal stations branching off that loop for your factories. The station entry and exit needs to be signaled so trains must enter on one track and exit on the other, which means putting the signals right after splitting from the main loop and right before joining the main loop on the way out. No signals are needed inside the terminal station. Nothing is signaled "two ways" with signals on both sides of the track.