Stevens Pass Centerbeams seem overly heavy

[CGrimes]

Has anyone noticed that the Steven Pass centerbeam flat cars need an awful lot of power to get them moving?

I had to put 8 CS44's on a 53 car train to get it up Steven's Pass and still could not maintain 20 mph.

The weights as shown for a loaded StP Centerbeam is 94t loaded & 31t unloaded in Quick Drive consist editor.

The Weights for Marias Pass Centrebeams are 39t loaded & 17t unloaded.

Quite a difference!

CG

[thecanadianrail]

Well a real centerbeam flatcar loaded would weight in around 100t in real life so the weight isn't really off in the measurements. Im not sure why 8 ES44's couldn't pull that short train over the hill, which ES44's were you using?

[CGrimes]

Well a real centerbeam flatcar loaded would weight in around 100t in real life so the weight isn't really off in the measurements. Im not sure why 8 ES44's couldn't pull that short train over the hill, which ES44's were you using?

I'm using the Steven Pass Route ES44's.

You are right according to BNSF (http://www.bnsf.com/customers/equipment/centerbeam-flatcar/) a 60 foot Centerbeam Flatcar can hold up to 100 tons.

[Ericmopar]

If I remember correctly, rule of thumb is to double horsepower and tractive effort for every 1% increase in grade. That would be logarithmic I think.
So, a train that needs 8000hp on level ground, would need 16000hp on a 1% grade, and 32000hp on a 2% grade and so on.

[thecanadianrail]

If I remember correctly, rule of thumb is to double horsepower and tractive effort for every 1% increase in grade. That would be logarithmic I think.
So, a train that needs 8000hp on level ground, would need 16000hp on a 1% grade, and 32000hp on a 2% grade and so on.

this page will answer all of that: http://www.alkrug.vcn.com/rrfacts/hp_te.htm

[Toripony]

This is just an observational reference... here in Oregon south of Eugene I routinely see short (25-30 car) loads of finished wood products pulling hard up grades around 2-3% using 2 heads and 1 pusher.

[thecanadianrail]

This is just an observational reference... here in Oregon south of Eugene I routinely see short (25-30 car) loads of finished wood products pulling hard up grades around 2-3% using 2 heads and 1 pusher.

Now this is interesting! Out here I will usually see a lumber train (mix of centerbeams and boxcars) of around 70-100 cars long going through the mountains on the CN mainline usually with only 1-2 locomotives. Granted the track doesn't quite hit 2% at its max but it still has a fairly steady grade between 1-2%. So now im left wondering what is correct?

[buzz456]

It's not just grade but curves.

[FourEightFour]

You could utilize the Cole formula:

Rolling resistance: 8 lbs per ton
Grade resistance: 20 lbs per ton per percent of grade
Curve Resistance: .8 lbs per ton per degree of curvature


Disclaimer: I use this for older equipment, as that is all I have to work with.

[Ericmopar]

The number of engines will also depend on what the railroad considers a tolerable line speed up the grade.
It also has to do with drawbar pull. If the train has enough power to get up the grade, but not enough DSP units to keep a drawbar or knuckle from breaking, they add units for that too.

[GreatNortherner]

Hi,

It's been my experience in RW that train weight and engine power usually result in maximum gradient speeds that are generally close to what Al Krug's tool calculates. I have also observed that many of the, especially older, US DLC cars are underweight in loaded state (if they can be loaded at all), which might contribute to the surprising effect when suddenly switching to cars with heavier loaded mass.

Link to Al Krug's RR Forces Calculator: http://www.alkrug.vcn.com/rrfacts/RRForcesCalc.html

Cheers,
Michael

[ErikGorbiHamilton]

ES44's in real life are really "Under Powered" when it comes to mountains

[BNSFdude]

ES44's in real life are really "Under Powered" when it comes to mountains

As a conductor, I may be over stepping my bounds of knowledge of train handling, but under what authority do you make this (false) statement? And what specific ES44 are you talking about? DC? AC? C4? They all have different characteristics from my experiences.