Train-VS-RT crane/lowboy Louisiana.

[rsb502]

I was wondering when this was going to get posted. At first I thought HOLY SHIT thats my old trailer. Upon further review not my old equipment. Taylor Trucklines in Mn. they just got into HH from what I heard. Think there hh days are over

was wondering if this was why you sold the truck,lol

[rsb502]

Today's RR crossings have computer circuits that will judge the speed of a train . Just throwing a pipe across the rails won't gt crossing gates to lower or a signal to drop to red. You would have to find the isolated sections of rail and short them all to fool the signal system computer into thinking a tran had passed. Todays signal systems are complex and they are built to avoid faulty signals and train location reporting....laying a pipe across May have worked 30 years ago but not in today's world.

Hate to break it to ya but they arent all new, we (CSX) just replaced part (not all) of the original signal system from the 1940's and 50's from the Chattanooga Subdivision. It would never have been replaced but it wouldnt work with govt mandated PTC so one section at a time its getting swapped out, but its still just a track shunt to start the grade crossing system , its more intuitive but you can still fool it with wire and a resistor.

[mowerman]

looks like they had plenty of time to stop....wow crazy ,,,,tough to watch...bob

[Brocky]

I am not a train man, but How Long does it take to stop a train?? From the number of cars which crossed the highway after impact it does not look like the engineer ever applied the brakes??? And the tank cars which derailed well beyond the crossing finally stopped it??

[other dog]

I don't know anything about trains either, but I used to know a guy that worked for the railroad and remember him saying they started putting on the brakes 2 miles from their stop. I don't know how fast they were going in the first place though, or how long the train was.

Unrelated, but a B model Mack-

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

[rsb502]

Train braking is terrain and condition Dependant, a decent rule of thumb is a 100car train on level track takes 1 mile from 50mph, if its down hill or wet or cold double the distance. The changes don't end there, most mixed consist trains average half loads half empties, coal, grain and tank trains are most always all loaded or all empty so again double the stopping distance. If there was a curve or building back up the track restricting vision of the truck the brakes may not have been activated till a couple hundred feet before the truck.

[other dog]

Train braking is terrain and condition Dependant, a decent rule of thumb is a 100car train on level track takes 1 mile from 50mph, if its down hill or wet or cold double the distance. The changes don't end there, most mixed consist trains average half loads half empties, coal, grain and tank trains are most always all loaded or all empty so again double the stopping distance. If there was a curve or building back up the track restricting vision of the truck the brakes may not have been activated till a couple hundred feet before the truck.

So, a hunnert car bananner train in Mississippi where it's all flat would mean the engineer spotted Marcel from about a mile away...sounds legit to me.

[rsb502]

Remember I said there was more to it,air brakes on trains aren't like truck brakes, there's no spring brake and only 1 air line thru the train. Train brakes work by pressurizing the "train line" to 90psi, once the train is aired up every cars reservoir and the train line are equal at 90psi. Okay so when an engineer applies the brakes he is reducing the train line pressure, he would make a 10psi set, reducing the train line by 10psi to 80psi. At that point the "triple valve" on each car releases air from the reservoir on the car to the brake chamber pulling rods and the brake shoes against the wheels. The more air is released from he train line the harder the brakes set on the cars......however! The brakes set from the front to the back as the train line pressure drops, not all at once it can take about a minute for all the brakes to come on, therefore adding to the stopping distance. Also once you release air from the train line there is no compressor on the cars to recharge it, you have to charge the train line by releasing the brakes to fill the tanks, so if you make a bunch of brake adjustments, or "sets" and then throw the train brake into emergency dumping the train line there may not be a lot of air to set the brakes very hard anyway. And now you know "some" of the rest of the story!

[mrsmackpaul]

I don't know anything about trains either, but I used to know a guy that worked for the railroad and remember him saying they started putting on the brakes 2 miles from their stop. I don't know how fast they were going in the first place though, or how long the train was.

Unrelated, but a B model Mack-

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

any body notice it looks like half the mud guard or fender or wing or what ever you yanks call it is missing

Paul

[Brocky]

84

Thanks for the explaination.. That helps me understand the situation better. If you have to release the brakes to recharge the system then how do you hold back a train on a long downhill like Cajon pass beside I-15 coming down int the LA area?? Are the engines able to do it like a truck with a Jake??

Brocky

[j hancock]

Dynamic braking is used downhill where the electric power motors are used as generators and either recharge the system or release the electricity through brake grid resistors located in the locomotive to the atmosphere via heat.

There was an axle electromagnetic retarder made in Spain by Ilasa used on truck trailers that could do the same thing coming down a hill. Not sure if they are still around.

[39 Baby Mack]

Jim,

Jacobs also marketed the Jacobs ER electric retarder for driveline application, sounds similar in operation to the one you mentioned above.

Ron

[Brocky]

Jim and Ron

Thank you.. Just had to get my head screwed on right this morning.

I now remember hearing about the generator type retarders out west.. I think the only one I ever saw was at the 2003 ATHS Syracuse show. Some one from Calif had a souped up supercharger Cummins engine mounted on a blue trailer and used one of those retarders to put a load on it. Straight pipe and it "TALKED"!!!

[farmer52]

Some trains that traverse steep grades use engines connected to the rear as "pushers" and "brakes". See this often on the Horseshoe Curve near Altoona, PA.

[rsb502]

For long downgrades the locomotive's will go into dynamic brake mode and the engineer will make a brake set and if needed make another set but once you start you need to be pretty sure of where you are going and what your doing. We have a helper district in Cowan Tn, they have been living trains over the mountain there since the early 1900's, most trains need help up but hold their own down so the helpers cut off on the move when the lead locomotive crests the grade (which is in the middle of one of the oldest tunnels too) look up Cowan Tn pusher and Cowan Tn tunnel.