TechFindings

Update 2013-05-03: Regarding GWR 5700

With the upgrade from Train Simulator 2012 to Train Simulator 2013 running steam locomotives (with manual fireman) was simplified. Among the changes were:

• Two injectors (both from 0-100) were replaced with a single On/Off
• No ejector
• No damper
• Blower used to be 0-100, now just On/Off
• Steam generation/steam consumption information was replaced with just a PSI value and a green (going up) or red (going down) indication
• Adding coal used to be 0-100, now just On/Off

Perhaps I have forgotting something. This is mostly a GUI change (to make XBox gamepad controls possible, I guess). The old values are still available using F5, and the old controls are still available if using the mouse to control the levers manually inside the cab (not showing the HUD at all, I have read). The physics are not necessarily changed.

Well, I like realism, but with TS2012 it was hard to figure out if some of those things really mattered (like the ejector) or if it was just decoration.

I decided to make some test runs with different settings/values, to find ideal operating values. The results surprised me a bit!

Test setup
I choose Quick Drive and the Black 5 (LMS B5 + 8Mk1s) steam locomotive. My test track is East Coast Main line from Thirsk to Darlington. I leave at 2AM, the skies are clear and it is spring.

I try to drive as fast as possible, within the boundaries for each test run. I dont care about any speed limits, but it is a good track and the tests are quite safe.

Regulator is normally at 100%. I lower the regulator only when I lose pressure and water level outside my target values. However, I never lower the Regulator while the Reverser is above 10%.
Reverser is kept as high as possible, and not below 10%. With possible, I mean that I must respect my water level and pressure boundaries. I start from 75% and gradually lower as speed goes up, trying not to waste steam during acceleration while keeping a good acceleration.
Pressure: For each run I have kept the pressure within a 5-PSI range. The baseline has been to keep it within 215-220 PSI. For lower pressures I have lost pressure in a responsible way (it has taken me a few miles to get down to target pressure).
Coal: For each run I have kept the coal within different ranges. When reaching the lower threshold I have opened until reaching the upper threshold and then closed until reaching the lower again. The coal has started at 66%, and typically I have kept it between 65-70%.
Water: In most cases I have maintained water level between 90% and 100%. That is, opening the injector at 90%, leaving it open until 100%. Occationally, I have let the water down a little bit more to maintain pressure, and occationally I have allowed myself to switch injector on/off within the 90-100 range to maintain pressure boundaries.
Blower has been Off except when I have written otherwise.
Brake is set to Running (7%) as soon as brake pressure is 21 PSI.

Measure points
I have measured time at three points:

• 15.05 miles before Darlington (At Northallerton platform)
• 6.0 miles bofore Darlington
• 2.0 miles before Darlington

Measurements have been made manually, so there is a risk I made a mistake with a measure point or two. When getting closer to Darlington speed limit is 25 mph, and my speed is about 80 mph, so no measurements are taken closer to Darlington than 2 miles away.

Results
When reading the table, compare everything to run 5 (for each run, only one parameter is different from run 5). I suggest you

1. compare 2,3,4,5,6 (pressure variation)
2. compare 1 to 5, and compare 7 to 5 (basic coal variation)
3. compare 0 and 5 – only difference is that 0 was run as the first drive after loading TS, while the other runs are run immediately after another drive
4. now feel free to look at 8-15

First and most shocking notice: on my computer I lose about 40 seconds the first time I run the scenario, compared to when I run it again (compare 0 and 5). Obviously a lot of things are not loaded or computed the first run, but cached for the second run.

Pressure is less important than I thought! Keep it below the emergency valve level (at 221 PSI) – in run 6 the Black 5 is constantly leaking steam to avoid over pressure. Keeping pressure as close to maximum as possible is obviously not of much importance; compare 3,4,5. Below 205 PSI some performance is lost (run 2).

The Blower has hardly any effect whatsoever in this situation; compare 5 and 8.

Coal and Fire management is clearly quite important, and it is not so obvious what point is optimal. In run 1 coal was allowed to drop from 66% to 60% before filling up for the first time – not a good strategy. In run 6 on the other hand coal was immediately loaded from 66% to 75% before closing for the first time – not a good strategy either. Slowly adding more coal (run 12) seems to be better strategy than the baseline (run 5) and slowly adding less coal (run 11) seems to be a slightly worse strategy. Never filling up coal is a disaster (run 10) – if your engine cant maintain pressure even if both regulator and reverser have low settings your fire is too little! Finally, the Automatic fire guy (run 15) lets the coal level drop to 62% and then kept it there with the doors open (not possible using the HUD in TS2013).

Water can be spent with a slight benefit (run 13). For maximum performance, do not arrive with a full boiler. This might be within error margin though. Notice that both with a -10/+10 strategy and a -10/+5 water strategy much running time is spent with the injector open – losing water level is much quicker than gaining it.

Regulator vs Reverser
In run 14 I decided to run with the regulator at 80% instead of 100% – turns out top speed for my train increased from 80.5 to 82 Mph! More torque? I first set regulator at 100% and lowered reverser from 75% to 30% as I picked up speed (keeping pressure around 220 PSI). After that I instead lowered the regulator from 100% to 80% to keep pressure constant. After that went back to operating with the reverser. This opens up the question that there must be an optimal reverser value for each situation… depending at least on speed, but possibly also the load and maybe more factors.

Conclusions and driving advice

1. If you are going for maximum career scenario scores, run the scenario twice and/or get better hardware 🙁
2. Avoid forgetting to feed your fire: open/close regularly and make it grow slowly
3. Dont waste steam: brakes at running and pressure always below 221 PSI
4. Allow yourself to operate below maximum water and pressure levels
5. Regulator/Reverser ratio is not obvious or trivial

Conclusions and driving advice may not apply to

• other engines than the Black 5
• scenarios with many starts/stops
• slower scenarios (uphill with load), in my tests I operated close to maximum speed
• scenarios with heavy load
• the exact same situation, in case game physics engine is updated

Driving a steam locomotive is supposed to be a black art. Each locomotive is unique. It is about listening and feeling. Some of my findings here were quite surprising too me, and I dont know if they are realistic, or just an effect of a limited physics engine.

GWR 5700
After driving the GWR 5700 a bit I made two observations. First, it starts at about 60% coal level. Keep it there, between 55-65%, or at least raise it very slowly. And, the Blower is very useful for Boiler Pressure when GWR 5700 stands still. I guess it should apply to all locomotives.