My wife and I were walking along the east esplanade of the Willamette River
in Portland late yesterday (Sunday) afternoon, and as we were approaching
the Steel Bridge, I heard the low rumble of a train coming down the adjacent
tracks from UPs yard in North Portland. Being somewhat besotted by trains,
I walked over to the cyclone fence to watch the train pass by, while my
wife rolled her eyes and patiently waited.
The track here bends around a grain elevator just to the north of the bridge,
and so trains slowly reveal themselves to onlookers, which adds to the fun
of watching them pass from that viewpoint. Trains can continue on south along
the Willamette and follow, more or less, the I5 corridor, or turn east and
head up the Columbia, alongside I84.
On this particular afternoon the lead locomotive rumbled by, and a friendly
engineer waved as he passed by. And then the locomotives just kept coming:
there were at least ten and maybe even as many as a dozen. I thought this
would be the longest train I had ever seen or heard of, but in fact only a
couple dozen cars, mostly empty box and bulkhead flats, rolled past before
the train came to an end.
And so my question is, why all the locomotives? Was this train destined for
some insanely steep grade? Would it pick up more cars elsewhere along the
course of its journey, or is it just a transfer of locomotives to another
location?
From time to time locomotives get inequitably distributed by the characteristics of the trains they haul.
One terminal I worked could either have a surplus of power or a power defecit depending on what commodities were being handled at the time.
Coal Trains would arrive with 3 units…The empties from these coal trains could be returned to the mines with 2 units creating a continuing surplus as long as coal was the only commodity the terminal was handling. Throw in an Iron Ore ship docking and moving it’s contents, it would now take 4 units to handle half the cars that the coal trains brought in with 3 units. For the duration of the Ore run the terminal was always in a power defecit situation and would need extra power to be operated into the terminal.
The power demands for specific areas of each railroad have their own needs. With locomotives being the big ticket investment item for the railroads, they don’t assign any more power to most trains that is needed to move the tonnage the train is carrying, it is also somewhat rare where the tonnage rating for a sub division will be the same in both directions…most of the time one direction will have a better tonnage rating than the opposite direction.
When an ‘extreme’ number of locomotives are on any run they are there for one of two reasons, they are working engines being repositioned to a location that needs them. Or they are shop engines being sent to a repair facility.
After the long (4-day) Thanksgiving holiday, the eastbound freight to which Wulfblat refers may have been peddling power for outlying locals. These would have been individual units that were serviced over the weekend at the Albina (Portland) diesel facility and then dropped off on the way to either Hinkle or Eugene. Some of the power could have been assigned to work trains as well.
Of course the units may have been dead-in-consist awaiting repair or periodic inspections (as required by the F.R.A.) at the Hinkle, Ore. diesel shop.
Exactly what was already said before, either these loco’s go back for maintenance after a faillure, or back to an other yard from where heavy trains leave and smaller and lighter trains return.
It can also have to do with the gradient of the line. One way perhaps 3 or 4 diesels are required while the other way, down hill 2 engines are enough, even with dynamic braking taken into account.
In NZ sometimes when the electrical section is switched off between Palmerston North and Te Rapa, one DX diesel hauls 2 or 3 dead electrics and then the 3 or 4 passenger wagons from the Overlander train in tow. This is the passenger train between Auckland and Wellington.
The sound is great when those 12 cylinder diesels have to work hard on a heavy haul and you enjoy the sound on the viewing platfrorm of the train.
See the answers above for details. For any one of the above reasons (and a few others), the power on that train must move East towards Hinkle. Only sufficient units to operate the train will be permitted to be on-line and the balance will be idleing and isolated so that their wheel-slip controls will operate properly.
Last night I was on a light engine consist of 8. (5 NS and 3 UP) We were taking them from a CSX crew and delvering them to NS yard in New Oreans. First trip I made of just locos.
You can count on this being a power balancing move. Portland to Hinkle is almost dead flat. The worst grade starts at the Steel Bridge and runs up Sullivan Gulch. I do not have charts, but suspect it is no more than 1% ascending Eastbound. I saw a good sized Eastbound at Bridal Veil the other day with two units, which is sufficient to move most anything between Portland and Hinkle. East of Hinkle is the Blue Mountains and a whole different story.
While railfanning the old ATSF line, a short TOFC went by at track speed with 8 locos. If only some were online, can the remainder be added to online by the engineer from the lead unit?
Are the air compressors from all 8 used to charge the train line?