Differences

This shows you the differences between two versions of the page.

--- transportation:train [2026/01/11 20:37] – [Caltrain] timb
+++ transportation:train [2026/09/03 00:36] (current) – [Articles] timb
@@ Line 163: / Line 163: @@
 https://shakeddown.substack.com/p/a-short-post-on-short-trains
+== How Railroad Crossings Work ==
+January 16, 2024 - Practical Engineering
+[Note that this article is a transcript of the video embedded above.]
+If you’ve ever ridden a bike, driven a car, or operated pretty much any other vehicle on earth, there’s a fact you’ve probably taken for granted: you can see farther than it takes to stop. Within the span between seeing a stationary hazard and colliding with it, you have enough time to recognize it, apply the brakes, and come to a stop to avoid a collision. Your sight distance is greater than your stopping distance; it sounds almost silly, but this is a critical requirement for nearly all human-operated machines. But it’s not true for trains.
+Engineers can see just as far as the rest of us, but the stopping distance of a fully laden freight train can be upwards of a mile. That means if an engineer can see something on the tracks ahead, it’s often already too late. So, trains need a lot of safety infrastructure to make up for that deficiency. For one: trains almost always have the right-of-way when they cross a road or highway at the same level, or at grade. The cars have to wait; And, we use a litany of warning devices at grade crossings to enforce that right-of-way and try to prevent collisions. In most cases, these devices have to detect the impending arrival of a train and give motorists enough time to clear the tracks or come to a stop. It sounds simple, but the engineering that makes that possible is, I think, really interesting, and of course, I built some demonstrations to help explain. This video is part of my series on railroads, so check out the rest after this if you want to learn more! I’m Grady, and this is Practical Engineering. Today, we’re exploring how grade crossings work.
+https://practical.engineering/blog/2023/12/29/how-railroad-crossings-work
@@ Line 845: / Line 855: @@
 https://www.thetravel.com/largest-underwater-tunnel-in-the-world-unused/
+====== Map ======
+== The world railway map ==
+https://worldtrainmap.com/
 ====== United States ======