Locomotives at each end?

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JazzDad

JazzDad

Gandy Dancer
OK, I admit it: I hadn't done much railfanning for years. I remember when you'd see a freight train with about 4 locos MU'd at the head end. Lately, I'm seeing all these trains on my local UP (formerly SP) line where there are 2 locos up front and 2 at the rear end. Is this some new trend? It makes sense; less stress on the the front cars of the train.
 
usually on the larger trains it is to reduce coupler stress as you say. On shorter trains or locals it is done to keep from having to back up long distances (the 2nd unit is usually offline and not really doing anything).

UP has been doing it for awhile down here, not because of the hills by any means! They experimented for awhile with extra engines (DPUs/Distributed Power Units) about 2/3 of the way back instead of at the end. Evidently the experiment ended because I don't see them that way any more. Today I saw one headed your way with 4 in front and 2 at the rear, and another eastbound with 3x2. Almost all of UP's non-locals are done with split power around here.

JazzDad: Where in SC Texas are you? Sounds like you are on/near the Sunset Line. I'm in Sugar Land during working hours, those tracks are about 50 yards from my office.
 


I was also told it was more economical and fuel efficient to run some power at the front and DPU mid-train or on the rear. Effectively, each group of engines is only pulling the cars behind it, so if you have 2 engines and 100 cars with both engines at the front, you have 2 engines pulling 100 cars, but if you put one engine on the front and one in the middle you have 2 engines each pulling 50 cars. I very simplistic analogy, but you get the idea.
 
Its about a few things... HpT (horsepower per ton), dynamic brake requirements/limitations, and drawbar (stress)limits. In comon sense terms....its all about train handling. Also when running DP trains you can run the front and rear units seperately. When you are going up a steep hill like the flyover at san bernardino, you can put the rear units in run 5 and the front in run 4, that way the rear pushes more than the front pulls, elimination the possibility of breaking a knuckle or ripping a drawbar completely out..... yes it has been done lol
 
Hey, Ken. I'm seeing these through freights along Hwy 90, near Columbus.

And yes, Fred, I used to see power in the middle of the train, but not so much any more.

My boss calls this area the rolling foothills of the hill country, so they're working the throttles a little bit out here.

The KCS grain unit trains really fly through this rural landscape.
 
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they do this in and around Chicagoland to get the trains up to speed faster and for better economy. I forget the figure one of the large railways gave but they say it will save them millions in fuel cost by running a loco on the rear. I think they call them a DPU? If I recall some rear units are unmanned and are radio controlled from the front locos? Looks odd to me but hey if it works try it?
 
The CPR runs some coal trains with end power for these reasons and one more. The train heading West has to reverse from the main up a spur East to the mine, then when it comes down reverse back to head East once on the main. This way it's ready to go no matter what direction it's heading.
 
bnsf's running 2*2 trough colorado springs lately but ive notesed the rear locos have etd
's on the couplers
 


BNSF does NOT "require" an ETD on the end of the train. The train can be put into emergency from the rear units which are controlled by the lead unit.
 
Laidoffsick said:
BNSF does NOT "require" an ETD on the end of the train. The train can be put into emergency from the rear units which are controlled by the lead unit.
Click to expand...

They must have an indication to signify end of train of some kind, a light or something?
 
The train I work is DP going westbound (down Cajon Pass) 50% of the time. Once in awhile we will have an ETD on the rear only because we will need an ETD for the eastbound trip the following day. The ETD isn't even cut in, it's just there for the ride.
 
I remember Conrail used to use a pair of GP-15-1s on their local freights around Latrobe,PA. They would run one on each end of the train or cut of cars. My guess is because they probably didn't want to have to turn around somewhere or run the loco backwards so when heading back the crew would just jump in the other loco. I imagine other railroads do that a lot too.
 
Many times its not because we "don't want to" turn around, its because there is NOT a place to do so. Deadend industrials spurs with no wye, no runarounds, or no sidings.

So you put a loco on each end of the cars, when you get to the industry, cut the rear unit off, shove your cars into spot, come back out and go against the rear unit, switch ends, and head back home. In Southern CA, we run baretables evryday with a 2 unit east/west consist. Run out into a siding, leave the empties in the siding for storage, switch ends and return to the terminal where you came from.
 
I work 3 days a week at an office about 80 yards from the BNSF main at the top of Cajon Pass, in Hesperia, and have a great view of trains passing by all day long. I'd say probably 80% of both UP and BNSF have power on both ends, always with new units. It's been my supposition that the GEVOs and SD70ACEs are optimized for this sort of running.

A few days ago, just as I was leaving in the afternoon, a consists of a dozen BNSF units roared past heading south, doing about 60mph. I had to run a few errands, but was still able to catch up to them on my way home, at the bottom of the pass, and take a few pics. Just a solid block of power :)
 


You know it's real funny when they need it on one piece of rolling stock ;)

DSC01863.png
 
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