Slack

[Anonymous]

How do engineers go about controling slack in a train? What indicators do they lok for to decide whether to add throttle or brakes and what type of braking?

[Anonymous]

Being a good engineer is all about maintaining tight control of your train. To maintain tight control of speed and slack you have to know where your train is, where your train is going, and where your train has been. All the hills and dips really make a difference on how your train acts. When the head end of the train starts going up hill (ascending) you need to add power then so the slack does not run in. I have been working on the railroad for 22 years and I have seen very serve slack action. When I was a rear brakeman on a train coming from Janesville, Wisconsin to Proviso Yard in 1984 we encountered slack action so bad that the conductors desk broke away from the wall, that is the main reason the railroads wanted to get rid of the caboose because there were a lot of personal injuries to the crew in the caboose.
Dave UP engineer

[Anonymous]

I agree with Dave, that you have to know where you are going, where you are at, and where your rear end of your train is. You also need to pay attention to how your train is made up, specifically where's the loads and empties. Sometimes, if you have a bunch of loads behind a lot of empties you have to wait a little bit before you do things, to let the loads either
a)get over the crest of a hill, or b)let the loads get to the bottom of a hill (so you don't get too fast). Also, a lot depends on what type of train you have, a stack train has very little slack in it (relatively speaking), while an auto train has huge amounts of slack (I've gotten on rack trains that were bunched up that the head end has move 2 or 3 car lengths before the rear even started moving). Generally, the company wants us to use dynamic brakes, that is what they preach, so that's usually the first choice, but there are circumstances (particullarly the light on the head end/heavy on the rear) where using the train brakes is much better. It's really just a judgement matter, depending on what the terrain is (uphill/downhill, undulating, flat), what type of train it is and how heavy it is, how much dynamic braking you have (engines),wind (yep wind will have a big effect on certain trains, particullarly stacks and empty coal trains), and whether you are stopping, slowing down(and how much you have to slow down), or just maintaining whatever speed you are going. It's also a feel type of thing, every train is a little different, you can have 2 very similar trains, and one will stop on dime (figuratively) while the other you sometimes wonder if it will ever stop. Hope this helps.

[Anonymous]

Desributed Power has greatly reduced slack in trains. almost to nothing at all.

[Anonymous]

When was the last time you were on the head end of frieght? The slack action in a train depends on type of cars and the engineer. If you have alot of autos or long draw bars in the train there could be alot of slack. A train with 10,000 feet of auto racks will have around 300 ft of slack in it. Trains this long are often the norm as most will know. If your engineer doesn't have control it will give you a good thump going down a grade.