Number of Locomotives on Stack Trains.

[Anonymous]

I have seen so much weard power on UP Stack Trains lately that I just don't know what to say anymore! For instance....................
There will be such as one Stacker will have 2 or 3 SD70M's pulling a Stack Train that will be over 2 miles long. And there will other times there will be other Stackers that will have some where between 5 to 10 Locomotives on the point and the Train will be under 1 and a half to 2 miles long! Very weard! I just can't figure them out!

[MP57313]

QUOTE: Originally posted by BNSF railfan.
5 to 10 Locomotives on the point

Power balancing? Where they need engines in another location and run them as part of a train instead of light?

[Anonymous]

Rail traffic does not present the situation where power naturally balances out.

Loaded cars weigh more than empty cars....if it takes 2 engines to haul a coal train over the road (assuming grades in each direction are comparable) those same 2 engine can haul about 3 times the number of empty cars as they can loaded cars.

Some terminals accumulate surplus power since most movements into the terminal are loaded trains and most movements out of the terminal are empties returning home. It is much more cost effective to return surplus power to where it is needed by adding additional power to a train that is operating to where the power is needed than by calling a light engine movement that may use multiple crews to get the power where it is needed.

[Anonymous]

BNSF Fan,
Take note of whether there is a trend... Your eastbound stacks will typically be 100% loaded boxes in your part of the world, whereas a westbound train may have some empties. Even though, to the casual observer, 2 trains may look the same, the tonnage in the boxes (or lack of tonnage in some boxes) could make the total weight of the train significantly different.

Also, as noted above, there's always the power balancing dillema. Right now is peak season for the UP. Intermodal is running at its heaviest for the year (pre-season fall retail rush). They're scrambling to get power where its needed to handle the trains.

[Junctionfan]

Chances are that if it is UP, they are using power to handle grades, speed and weight. Also they like any other railroad, do power shifting. I have seen this on video and givin an explanation by the producer of it. CN intermodal heading from Toronto to Chicago usually has 2 to 3 engines had 12 because several of them were to get maintance in U.S some place.

Depending on where you saw this, I would imagine that Chicago and North Platte is where power is stored, maintained and in demand for other trains so power moves are constant and frequent just not on the same train but sent out on any train when required. It is the same as that I have seen the odd boxcar or autorack on an intermodal train but is not usually the norm.

[ShaunCN]

yesterday i saw 5 CN units on a intermodal train... was quite a sight!!! all where big locos too Dash9's and SD75I.