What causes derailments, why are they so common?

I think that safety should be a huge factor in a method of transportation like a train. But these days you always read about a train striking a car, god forbid a big truck and everyone dying. Why don't we put more money into making our railroads safe? If trains are so supposedly big and powerful why do objects that are 1-1000th of their mass cause them to derail? Why is our safety and engineering so poor?

What are your thoughts?

I guess there are many thoughts floating around the web, but here's some:
1.) There are lots of derailments happening, but these are usually very minor ones (in yards, or sidings) at low speeds, and often are rerailed without incident. Lots of subpar & wonky track around (hence the various classes of track - Class I track is 10mph max...which is pretty dang slow!)
Here's some FRA track classes & speed limits

2.) Your examples are more grade crossings - well, this is always a big topic of discussion here, but the main problems (at least in the US) is there are lots of Grade Crossings (and need to be - you can't justify a bridge for a crossing of say 50 vehicles/day, yet there needs to be a connection to travel from one side of the tracks to, say a main road - even the UK, with supposed isolated main lines, has lots of level crossings - I do think for FRA Class 6 or higher you need no grade crossings, or some sort of 4 quadrant gates)
Now, a 2 ton car vs. a 200 ton locomotive, if it doesn't get wedge under the loco, the loco usually stays on the track...but a 40 ton truck, that's about a fifth of the loco's weight, hmm now you have a problem).
Major incidents (which tend to make the paper as apparently they are so photogenic), those are investigated rather heavily.

PC789 wrote:I think that safety should be a huge factor in a method of transportation like a train. But these days you always read about a train striking a car, god forbid a big truck and everyone dying. Why don't we put more money into making our railroads safe? If trains are so supposedly big and powerful why do objects that are 1-1000th of their mass cause them to derail? Why is our safety and engineering so poor?

What are your thoughts?

Congratulations on making your first post! :-)

I think you're a bit mixed up. Are you asking what causes derailments? Or are you asking about grade crossing safety? Grade crossing accidents where truck drivers and automobile drivers cause wrecks are due to the driver of the vehicle breaking the law and driving into the path of an oncoming train. What's more, I don't know of many car/train collisions that result in derailments. Derailments are caused by many factors, and range in severity from minor to catastrophic.

As far as investments in safety, the railroads do all they can. But you can't stop stupid, no matter how much money you invest in bells, crossing gates, warning flashers, and stop signs. As for these big and mighty objects, a "tiny" two-ton object like a car, or a heavier object like a truck won't cause a derailment. The truck or car gets pulverized every time. And the train crew that survives is traumatized for the rest of their lives.

Read up:

http://www.oli.org/

http://safety.fhwa.dot.gov/xings/index.htm

Watch these:

http://www.youtube.com/watch?v=zCrHwqGfkYs

http://www.youtube.com/watch?v=qUNZO1Xti1E

http://www.youtube.com/watch?v=Mf3v6bxblSQ

http://www.youtube.com/watch?v=hWToJxKYRSc

PC789 wrote:I think that safety should be a huge factor in a method of transportation like a train. But these days you always read about a train striking a car, god forbid a big truck and everyone dying. Why don't we put more money into making our railroads safe?

Like how? Maybe the train should have to obey a speed limit? Maybe the train should blow its horn at the car? Or signs and pavement markings warning people about the crossing? Or they should have flashing lights and a bell? Or maybe even gates that come down and block the road? Or a public education system which teaches children "If you get in the way of a train, it cannot stop and WILL hit you" and "If you get hit by a train, you will suffer an inelastic collision, and you will take on the train's velocity which will undoubtedly cause a large impulse to your body."

If trains are so supposedly big and powerful why do objects that are 1-1000th of their mass cause them to derail?

Um, hitting things is rarely the cause of a derailment. Usually a derailment is caused by a technical problem in the rails which causes multiple cars to leave the tracks. Could be a broken rail head, or a sun kink, or spread gauge.

What are your thoughts?

I think you wouldn't care to know what my thoughts are right now.

First, as other posters noted, we have to separate derailments and grade-crossing collisions from railroad accidents in general, The first two make up a very large proportion of all the incidents taken together.

Most derailmets occur in yards, or on less-used trackage. Since higher speeds are seldom encountered here, publicity isn't likely. It's only when a large number of cars derail at speed that the wreckage is big enough to attract reporters and lawyers.

Also worth noting is the fact that major dertailments tend to be more common around this time of year due to the spring thaw, when changes in the underlying ground can disturb a track's alignment. The problem also spiked during the late 60's and early 70's, when financial difficulties caused some lines to scrimp on maintenance, and larger cars stressed the trackage in ways not previously encountered. Advances in the technology of trackwork and healthier finances have definitely improved things here.

As to grade crossings, I continue to be amazed by the number of drivers who don't understand enough about the laws of physics to avoid making some dumb comment like "Why didn't the train stop?" In some cases, this happens because the line in question has been upgraded to allow for higher speeds, and the motorist just doesn't make the connection.

Finally, let's remember that railroads make a big, juicy target for legal vultures of the ambulance-chaser persuasion, and they're not going to present their usual clientele with both sides of the story.

Another thing to consider is that while serious derailments or tragic grade crossing accidents make headlines, there is no "news" in the tens of thousands of trains which routinely arrive at their destination safely. The number of incidents is small when compared to the overall number of trains operated.

Sorry for being unclear. I think that trains and track should be engineered better so that there are never any derailments, even if a car or truck collides with a train. I don't know if most of the time it's due to bad track or there are not sufficient enough guards under trains but something could be done. Or even connect the wheels to the track better with bigger flangs. Since trains cannot stop or swerve out of the way they should be built tougher than road vehicles to be able to keep passengers safe. The amount of deaths of train passengers due to level crossings is higher than it needs to be, possibly even more so in the united states.

Um, hitting things is rarely the cause of a derailment. Usually a derailment is caused by a technical problem in the rails which causes multiple cars to leave the tracks. Could be a broken rail head, or a sun kink, or spread gauge.

http://www.nytimes.com/2005/01/26/natio ... &position=

http://query.nytimes.com/gst/fullpage.h ... A96F958260

http://www.foxnews.com/story/0,2933,289678,00.html

http://youtube.com/watch?v=DYoF6IionD8

http://www.theaustralian.news.com.au/st ... 02,00.html

http://www.trainweb.com/derailments/2002e14a.html

While we're at it lets make planes that don't crash or boats that don't sink. Even if a train derails because of a grade crossing accident you seem to be of the idea that it's the railroads fault for not having better rails and it's not the drivers fault for going around gates or racing the train. What do you want the railroad to do, stupid-proof every little aspect of its operations?

PC789 wrote:Since trains cannot stop or swerve out of the way they should be built tougher than road vehicles to be able to keep passengers safe.

So we should make trains more durable so as to protect auto passengers who negate safety devices? If people stayed off the tracks, when the train is coming we wouldn't have this problem. Why don't people have to become responsible for taking precautions for their own safety like stopping when the gates are down or when the lights are flashing, instead of ignoring them?

A) Safety is a huge consideration. Railroads spend big bucks for "safety programs".
B) There is no short term financial reward for safety.
C) Railroads don't "fix" until it "breaks".
D) Railroads believe in making rules to prevent accidents.
E) Most derailments occur due to either stupid mental mistakes or mechanical failure.

Realistically, railroads haul thousands of freight cars, thousands of miles daily without incident. I think the last derailment that I was involved in was some twenty years ago (Now, I'll probably have one tomorrow) when a rail turned over on a yard lead. Obviously when a train make a spectacular incident it brings in the news media (who don't usually have a clue as to what might have happened, but are just looking for some story). Also, the sheer mass of a train makes for a spectacle.

Another point is that just as the vast number of car wrecks make them common, the small number of train and plane incidents make them more newsworthy.

More railroad emphasis on inspecting train cars during inbound train inspection (although I don't know how to inspect cars for knuckle or drawbar weakness), fixing mainline sloworders (if there's a slow order , must be a track problem) and upgrading some "other than main track" sections would help eliminate some derailments.

"Since trains cannot stop or swerve out of the way they should be built tougher than road vehicles to be able to keep passengers safe."

This is starting to get silly. Have you EVER seen a train you would consider less "tough" than a road vehicle?

I can think of only one or two occasions where the highway vehicle might pose more of a threat, A truck hauling gasoline or propane is one. But the structural integrity of the train would aggravate, rather than mitigate, the effects of the impact here.

A still-more-dangerous scenario might involve a flatbed hauling structural steel. But regardless, the fault would lie with the driver of the truck.

And on that note, I might have to add, as a one-time motor freight dispatcher, that the competence of line-haul drivers, taken as a group, has declined in recent years. This is due largely to to the replacement of retiring drivers by recent immiogrants who speak English only as a second language, and are not as familiar with all the nuances of our complex society.

As for the quest for absolute security, Mr. PC789, I used to sell it; it came in very small parcels of land -- three feet wide, ten feet long, and six feet deep.

PC789 wrote:Sorry for being unclear. I think that trains and track should be engineered better so that there are never any derailments, even if a car or truck collides with a train.

I think the best solution would be anti-vehicle missiles mounted on the hood of every locomotive. When the engineer sees a vehicle in the path of his train, he shoots off the missile and blows up the vehicle. It would be too bad for the vehicle's driver, but it would give them a much better incentive to STAY OUT OF THE WAY.

Let's build all cars and trucks out of NERF material, and the fronts of locomotives out of sneaker-toe material. NERF car gets stuck on the track? Sneaker-toed locomotive easily punts it out of the way!!! Problem solved. The NERF material should keep the occupants safe. Haven't figured out a way to keep the sneaker-toed locomotive from starting to stink, after a few months, though.............

look at this train, then look at the one in the video, if we used locomotives like more often for passenger trains there would be far fewer rail fatalities.

http://www.youtube.com/watch?v=Rp-GzO7q0c8

PC789 wrote:look at this train, then look at the one in the video, if we used locomotives like more often for passenger trains there would be far fewer rail fatalities.

Why? It sure looked to me like there was NOTHING LEFT BUT SPLINTERS out of that log truck. Look, PC789, it's a simple matter of the laws of physics. Train has a certain speed and mass the product of which is momentum. When something with a certain amount of momentum hits something else of much smaller mass, there really isn't any question of the outcome. Whatever it hits will receive a large enough impulse for its velocity to instantly match that of the train.

Any human which receives that magnitude of impulse to their body is going to die. Physics ... not just a good idea ... it's the law.