Frost can be hard to see, especially if it starts to settle on everything at night, as it usually does, and after the train is underway. If you begin a trip on dry rails, frost can slowly begin to settle on everything without being noticed at all. Once it is there, the ties and ballast tent to sparkle more than usual in the headlights, but as it accumulates, this is can easily go unnoticed. Of course, if it goes unseen, it will be noticed the first time an attempt is made to stop or start the train! At first, when power or braking force is still relatively low, the wheels might just squeal a little, but as more power or braking force is applied, they will lose their grip on the rail completely and the entire locomotive will shudder and shake as the wheels slip and try to grab some rail again. Usually when this happens, I do a quick evaluation of the distance yet to be covered and the amount by which I need to reduce speed. If I only need to lose a couple of miles per hour, often I will use the terrain to do that. Even along the river, the track is not perfectly flat. There are lots of small undulations in the tracks, and knowing where the tracks turn uphill, even slightly, can be helpful. These small uphill areas can be used to scrub a few miles per hour off of the speed of a train. The situation is a little different if the train is headed downhill, or if a lot of speed must be lost. Most uphill areas on the Forsyth Sub are not long or steep enough to bring a train to a stop from track speed, using just gravity. If I have to slow down significantly or stop, and the wheels do not grab rail the way I want them to, I do not even hesitate to use the air brakes. By using the air brakes, the braking force gets spread throughout the entire train, and I do not have to depend entirely on the dynamic brakes, on the locomotives, to control the speed. Sometimes the air brakes work well, and sometimes the do not. I always figure if they do not work well, I can set more air, and if they work better than usual, I can release them sooner and just go slow for a little longer. I would much rather be going slow or stop short instead of running too fast into an area or sliding past a point where I was supposed to stop. It is much easier to stop short and pull up than try to explain to the Road Foreman why the train slid 30 feet past a stop signal!
Fresh snow can be as slippery as frost, but it is much easier to see at night. Of course, its accumulation on the tracks is quite obvious, and when snow is falling, it is usually piling up on the windshield and all over the locomotive too. While frost can go somewhat unnoticed at times, snow does not. Besides slippery rail, snow presents another problem - slippery brakes. If the snow is higher than the top of the rail, the wheels can start to pick it up, and then it gets pushed up between brake shoes and wheels. When a brake application is made, the snow has to be melted off the brake shoes before they have much effect on the speed of the train. This increases the time from which a brake application is made to when that application can be felt and is effective. This is another reason I usually set air right away if the dynamics begin to slip. Once the snow flies, extra time will be needed before the air brakes are working as hard as they normally do. Once again, it is better to be early with that than late! Fortunately, we have not had any significant snowfall yet.
Starting a train on slippery rail can be tricky, but it is usually less stressful than stopping. Modulating the amount of power going to the wheels, and using sand are the tricks to starting. When slippery rail is anticipated, it helps to use the sanders to stop, so that the locomotive is sitting on sanded rail when it is time to move again. The fine sand, which is carried on locomotives, can be directly applied to the rail through nozzles mounted just ahead of each set of wheels. While sand does not substitute for dry rail, it can make starting and stopping much easier, because it does help to increase the traction between the wheels and the rail. Essentially, it gives the wheels something to grab, when a lot of power or braking force is applied.
Besides slippery rail, fall is the season for broken rails. As the temperatures cool, the steel begins to contract, which puts more stress on the rail. If rail was laid during the summer, when the weather is hot, and the rail is in a more expanded state, it will all begin to contract and can break under the stress. Several nights ago, we discovered a broken rail. When the rail breaks, the signals governing movement into that signal block will display a red aspect. In the case of the other night, this was a Stop and Proceed indication, which is exactly what we did. Whenever we proceed at a Stop and Proceed indication, we have to be moving at restricted speed, which is a speed that allows stopping the train within half the range of vision, not exceeding 20 mph, on the BNSF. Other railroads may limit the speed differently. We are required to be able to stop short of obstructions in the tracks, other trains, or men working. Broken rail is actually not something we are required to stop for, but we must be on the lookout for it whenever we are moving at restricted speed. Most of the time, when a rail breaks, the ties hold everything in alignment. If we were to put a large braking force on the rails to try to stop for a broken rail, it could push things out of alignment. Also, it can be difficult to see broken rail from the locomotive, until it is about to go under the locomotive. Usually it is not discovered until the wheels go over it, with a much louder clack than a normal joint. Several nights ago, we passed the Stop and Proceed signal, and my Conductor and I both commented that it was probably a problem with a rock slide fence that is in that block. We went by the slide fence and noticed nothing wrong with it, and then about 500 feet before the next signal, when we were just about on top of it, we noticed what looked like a possible broken rail. We reported it to the dispatcher and continued over it slowly, until the entire train was clear of it. Sure enough, they sent maintenance out there, and it was indeed a broken rail. They spliced in a new piece of rail and bolted it all together. It will probably be welded later, when it gets colder, so it does not break again. While broken rails do not occur that frequently, they do tend to happen more often in the fall, as the weather cools and the steel contracts and becomes more brittle. They can happen any time of the year though. Once the whole train was over the break, we were back on clear blocks, so we picked the speed up to normal track speed.
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