Double Heading Trains, when is it worth it?

[PhantomVector]

While I knew of the practice in reality, I hadn't realized it was something I could do ingame. Now that I know, I am totally ready to try it out. With that said, like the title asks, when is it worth it? Both money wise, and how do you tell a train could use a second locomotive?

[corpowat]

when u have a long consist and some grades that will be when u need to double head and it is cost effective? or do it anyway its your game?

[RabbitRidge]

In my experience, only if a single Loco doesn't have enough power to make it across the Route inclines and you don't have any other single Loco options in the vanilla game. It's much better to build rails as flat as possible (end to end) provided the funds are available.

[Vimpster]

There are also traffic concerns that can benefit from double heading. For instance if you have several lines that share the same track than it will generally be advantageous to make fewer longer trains rather than more smaller trains so that trains from different lines are less likely to be getting in each others way.

In other cases it is sometimes more cost effective to have two weaker locomotives pulling a train rather than one strong locomotive. The two weaker ones might have better stats combined than the stronger locomotive but at a cheaper total cost.

[RabbitRidge]

Originally posted by Vimpster:

In other cases it is sometimes more cost effective to have two weaker locomotives pulling a train rather than one strong locomotive. The two weaker ones might have better stats combined than the stronger locomotive but at a cheaper total cost.

I agree, but in that case you have to do the math of potential speed (which translates into ticket prices considering the whole train potential speed) and the additional maintenance costs but I haven't ran into that situation yet with rail building as I described.

[Autocoach]

Lots of sound advice here , other than the look generally you have two related situations .

As Vimpster states you have correct trains that accelerate fine but they get in each others way (waiting to enter platforms usually) and you can simply join two trains together (probs locos at the front) to reduce the amount of space required on the line etc .

The other is where the train is too weak , if a train is rated 'poor' it is worth considering adding extra power in the form of another or more powerful loco and if it is going uphill etc . To check the rating of a train you have go to the details tab and hover over the power rating for more detail.

[RabbitRidge]

Flat rated Lines is a relative term, there is a slope ratio which I haven't bothered to mathematically determined yet (I have evidence of 37m height deference that is still considered Flat on a relatively short line, but I'm sure someone has calculated the total length/height ratio by now). I've used one 2-6-0 Mogul to pull 34 tank cars full of oil up that very same gradual total hill length and appreciated the slow speed (about 21km/h top speed, not enough power even for Medium grade) because my Horse Carts would have never be able to keep up. Basically if you keep the tracks rated Flat throughout, your golden to rely on the Flat acceleration rating (I was able to transport greater than 50 full tank cars [7 capacity individually] in a test before giving up on the limit).

Edit: I have nothing to offer regarding sharing tracks and signals, don't use them (IMHO a train stopped anywhere not in a station is just wasting money). I guess you could sum up my whole philosophy that it is better to spend money upfront on the underlying infrastructure for the long term gain.

[Stealthy]

Double or even triple heading makes sense. Not only you can use longer trains but you maintain higher speeds easier and thus your rolling stock makes more money earning trips. Ticket price is always counted directly from the potential maximum speed defined by either locomotive or wagons. Nothing else matters for that, so double heading will not increase the potential maximum in any level, it just ensures that your train can actually reach it.

My rule always is to never exceed kN pulling power in tons for wagons. So if locomotive has 200kN pulling power, i'll never add more than 400 tons of wagons to it, excluding cargo weight. This ensures decent enough performance.

[Stealthy]

Originally posted by RabbitRidge:

I agree, but in that case you have to do the math of potential speed (which translates into ticket prices considering the whole train potential speed) and the additional maintenance costs but I haven't ran into that situation yet with rail building as I described.

This here for example, if complete nonsense. It doesn't work like this. Ticket price is defined by the speeds indicated at the specs for the locomotive or wagon. And lower one is always the limiting factor which specifies the ticket price. 200km/h locomotive on 150km/h wagons will result to 150km/h max speed for the train, ticket price is defined by 150km/h. Can the train actually reach that is totally irrelevant.

kN to tons on later post gives a simple rule of thumb how many wagons one locomotive can pull without losing too much speed and still having decent acceleration. If you double or triple head your train, multiply kN by 2 or 3 and you see the benefits. One locomotive with 500kN can pull same amount as 2 locomotives with 250kN each.

Power gives the speed, kN gives the tonnage.

[Autocoach]

If we stick to Transport Fever rather than the more complex relationship between power / top speed and tractive effort then I would note the following .

Tractive effort is only of limited importance here , it is either in whole or part responsible for the ability of a train to get started and reach 20kph (13mph) I believe. Taking an example of a couple of early years mods , the stronger loco with double the tractive effort of the weaker one (identical power) can reach the set top speed of 31mph for a set weight of train 4 seconds quicker than the weaker one . Although a benefit it is not a great one and certainly would not allow for the train to be doubled in length .

In Transport Fever power and top speed are what it is about , so a low powered loco with a high top speed can only make use of this top speed -actually get to it- with a short train .

Although the revenue per trip is dictated only by the theoretical top speed of the slowest vehicle on a line , the number of trips you can make could make per year can be greatly increased by having trains actually go faster - which is common sense really.

[BrigadierRosen]

Check the wiki or go on youtube as they usually will have a more detailed explanation.

Otherwise dont bother, unless your strapped for cash or two locos are more efficient than the more expensive one there really isn't any reason to have two if the effciency increase is negligible.

[Vimpster]

Perhaps a slight derailment of the topic, but related and in response to the current comments; I did a test and got some rather surprising results. It was my understanding that tractive effort both increased the early acceleration from a stopped position, as well as increasing the minimum
top speed on any given slope. It turns out, according to my tests, that only the first part is true.

First test between 2 trains:

Total Weight          Traction 
        - 280tons              - 150kn
                    Power          Min. Top Speed on Full Grade          Distance to Reach 50kph on Flat
1st train     - 1600hp      - 58kph                                    - 210m 
2nd train    - 2700hp      - 92kph                                    - 130m

Second test between 2 trains:

Total Weight          Power 
        - 700tons              - 4079hp
                    Traction          Min. Top Speed on Full Grade          Distance to Reach 50kph on Flat
1st train     - 151kn           - 58kph                                  - 250m 
2nd train    - 363kn           - 58kph                                  - 210m

Third test between 2 trains:

Total Weight          Power 
        - 512tons              - 2237hp
                    Traction          Min. Top Speed on Full Grade          Distance to Reach 50kph on Flat
1st train     - 164kn           - 44kph                                  - 285m 
2nd train    - 291kn           - 44kph                                  - 280m

Apologies for the poor formatting. Was attempting to make it easier to read.

[RabbitRidge]

Originally posted by RabbitRidge:

Flat rated Lines is a relative term, there is a slope ratio which I haven't bothered to mathematically determined yet (I have evidence of 37m height deference that is still considered Flat on a relatively short line, but I'm sure someone has calculated the total length/height ratio by now). I've used one 2-6-0 Mogul to pull 34 tank cars full of oil up that very same gradual total hill length and appreciated the slow speed (about 21km/h top speed, not enough power even for Medium grade) because my Horse Carts would have never be able to keep up. Basically if you keep the tracks rated Flat throughout, your golden to rely on the Flat acceleration rating (I was able to transport greater than 50 full tank cars [7 capacity individually] in a test before giving up on the limit).

Edit: I have nothing to offer regarding sharing tracks and signals, don't use them (IMHO a train stopped anywhere not in a station is just wasting money). I guess you could sum up my whole philosophy that it is better to spend money upfront on the underlying infrastructure for the long term gain.

Now that I'm basically over my illness, perhaps I should clarify that time was the restricting factor of the short line acceleration described (not power).