tractive effort vs speed question.

[Ericmopar]

I was wondering what numbers in the tractive effort vs speed files do what.
I've got a F40ph I want to modify since even with Fanrailers mods the F40PH pack01 engines will pull a 9 car consist up a 1.1% grade in notch 2.
If I'm on the wrong track, snicker, he he, tell me oh mighty engine builders.

[mrennie]

I was wondering what numbers in the tractive effort vs speed files do what.
I've got a F40ph I want to modify since even with Fanrailers mods the F40PH pack01 engines will pull a 9 car consist up a 1.1% grade in notch 2.
If I'm on the wrong track, snicker, he he, tell me oh mighty engine builders.

They scale the starting tractive effort (given elsewhere in the blueprints) to give you the instantaneous t.e. at the given speed. For example, say you have a value 'v' at 0mph, and 90% of v at 20mph, it means that at 20mph the t.e. is 90% of the starting t.e.

[Ericmopar]

Well...
What does that translate to when looking at this?

Tractive Effort curve.JPG

[dtrainBNSF1]

I was wondering what numbers in the tractive effort vs speed files do what.
I've got a F40ph I want to modify since even with Fanrailers mods the F40PH pack01 engines will pull a 9 car consist up a 1.1% grade in notch 2.
If I'm on the wrong track, snicker, he he, tell me oh mighty engine builders.

They scale the starting tractive effort (given elsewhere in the blueprints) to give you the instantaneous t.e. at the given speed. For example, say you have a value 'v' at 0mph, and 90% of v at 20mph, it means that at 20mph the t.e. is 90% of the starting t.e.

That may be so for steam locomotives, but it's different for diesel blueprints. In diesel blueprints you have a specific amount of t.e. in units of kn (the y-variable) at a specific speed in mph (the x-variable).

What FanRailer does to calculate this figure is this: kN= (kW at rail x 3.6) / speed (kph)

I've noticed that some of FanRailer's mods seem to outperform the prototype, and it's beginning to make me wonder if the MaxPower line really is in kW and not in hp; horsepower is the measure of a locomotive's ability to use its tractive effort to move a load at speed. If that's the case, it may explain why DTG's ES44ACs are usually set at 3100.9 and not 4400.