The Dangers of Train Yards, Through the Eyes of Railroad Employees • Hacker News Board

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#11

Post by dredmorbius » Tue, Jul 03, 2018, 5:36 PM UTC

ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

My experience is largely with bicycles (you're very aware of the energy input/output), automobiles, and boats, but thinking of moving vehicles as momentum systems, to which energy can be added or removed, is useful.

On a bike, you maintain a steady speed by matching drag losses with the energy you're putting into the pedals. Braking and other actions cost you energy you've put in.

For automobiles and trucks, added mass has a significant change to momentum, and I feel that. Boats, from a row or sailboat to a 30m+ power vessel, have their momentum, drag, and interaction with water, waves, currents, and wind.

Trains are a whole 'nother ballgame.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#12

Post by TylerE » Tue, Jul 03, 2018, 5:37 PM UTC

lbriner wrote: post #6

Because of signal sighting rules in the UK, we experienced a lot of trouble upgrading lines to higher speed. All of a sudden, that signal that you could see for 10 seconds could now only be seen for 8 due to a bridge or whatever. Muchos dollars relocating signals and in some places not being able to increase the line speed at all. Boring but very real reasons why we "can't just update things"

Dunno why they don't just go ahead and bite the bullet and go to 100% in-cab signaling. The technology has worked for decades and has been deployed on many lines, including a few in the UK.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#13

Post by sandworm101 » Tue, Jul 03, 2018, 5:43 PM UTC

ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

>> 5mph would take nearly 1000' to bring to an "emergency" stop.

That seems far fetched. 1000' is a long way at 5mph. The number of engines doesn't matter. Each car has its own brakes in an emergency. Cut pressure in the line and every car will brake itself. Perhaps they meant situations involving hills, not uncommon for ore trains heading from mines.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#14

Post by lucb1e » Tue, Jul 03, 2018, 5:44 PM UTC

Historical, not current ones. I was talking to some friends about it just yesterday and was looking forward to the driver's point of view.

Also, cookie wall. So the TLDR is that in the past, more people needed to be employed on a train. The diesel came and they could redesign the locomotives so no big boiler was in front which blocks visibility. Problem solved for the railroads, but people unemployed. Apparently there are some historical pictures that they took on rail yards to prove the visibility issue.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#15

Post by dmckeon » Tue, Jul 03, 2018, 5:45 PM UTC

Not to make light of railyard hazards, but:

> the union had more than 30 railroad employees take photos of their workplace in an effort to demonstrate the hazards firemen could help navigate around.

suggests that the presumably union workers may have tended to choose to take photos of the more (or most) dangerous locations.

For a company perspective from the 1940s, see ""Why Risk Your Life?" -- 1940s Railroad Safety Film" https://www.youtube.com/watch?v=BqpayZ2JqlU

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#16

Post by bigjimmyk3 » Tue, Jul 03, 2018, 5:55 PM UTC

sandworm101 wrote: post #13

ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

>> 5mph would take nearly 1000' to bring to an "emergency" stop. That seems far fetched. 1000' is a long way at 5mph. The number of engines doesn't matter. Each car has its own brakes in an emergency. Cut pressure in the line and every car will brake itself. Perhaps they meant situations involving hills, not uncommon for ore trains heading from mines.

A train's emergency braking system is somewhat sacrificial (using it can damage engines, cars, etc.) so you're probably correct. I'd say that in either case, most people who are not "train people" will dramatically underestimate the required stopping distance. The mass of a fully loaded train is surprisingly large.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#17

Post by regularfry » Tue, Jul 03, 2018, 6:00 PM UTC

Just as interesting, linked from that page: https://www.atlasobscura.com/articles/pointing-and-calling-j...

Now I'm wondering about the cross-over between that and rubber-duck debugging.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#18

Post by kqr » Tue, Jul 03, 2018, 6:01 PM UTC

dredmorbius wrote: post #11

ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

My experience is largely with bicycles (you're very aware of the energy input/output), automobiles, and boats, but thinking of moving vehicles as momentum systems , to which energy can be added or removed, is useful. On a bike, you maintain a steady speed by matching drag losses with the energy you're putting into the pedals. Braking and other actions cost you energy you've put in. For automobiles and trucks, added m…

> On a bike, you maintain a steady speed by matching drag losses with the energy you're putting into the pedals. Braking and other actions cost you energy you've put in.

As does the frequent mistake of putting weight on the rear pedal. Realising this made me understand how little energy it really takes to keep a bicycle going, given the correct gear.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#19

Post by kposehn » Tue, Jul 03, 2018, 6:03 PM UTC

TylerE wrote: post #12

lbriner wrote: post #6

Because of signal sighting rules in the UK, we experienced a lot of trouble upgrading lines to higher speed. All of a sudden, that signal that you could see for 10 seconds could now only be seen for 8 due to a bridge or whatever. Muchos dollars relocating signals and in some places not being able to increase the line speed at all. Boring but very real reasons why we "can't just update things"

Dunno why they don't just go ahead and bite the bullet and go to 100% in-cab signaling. The technology has worked for decades and has been deployed on many lines, including a few in the UK.

Cab signaling requires a different set of standards in order to provide the necessary level of safety.

Cab signals are (usually) transmitted through the rail and picked up by a special receiver on the leading axle of the locomotive. Each locomotive has to be equipped and the rails themselves have to be checked and blocked. This also means the rails have a higher maintenance requirement as opposed to lineside signals which can be more easily maintained.

However, some countries (Brazil predominantly) have embraced a GPS based cab signal system where lineside signals are almost totally eliminated. However, this was done with federal subsidies to cover the expense iirc.

Another example is the US Northeast Corridor where cab signals are used along with lineside signals to provide a level of redundancy at speed.

Unfortunately there’s no easy solution, but I lean towards the Brazilian GPS based systems from Wabtec.

Re: The Dangers of Train Yards, Through the Eyes of Railroad Employees

#20

Post by kposehn » Tue, Jul 03, 2018, 6:05 PM UTC

sandworm101 wrote: post #13

ChuckMcM wrote: post #9

I got a chance to drive a couple of different engines at the Plumas rail museum. And one of the things that does is help you internalize the amazing amount of mass and momentum a train carries around all the time. The engineer who was with us spoke of freight trains that were a hundred cars of iron ore that, even though they were travelling at only 5mph would take nearly 1000' to bring to an "emergency" stop. While I…

>> 5mph would take nearly 1000' to bring to an "emergency" stop. That seems far fetched. 1000' is a long way at 5mph. The number of engines doesn't matter. Each car has its own brakes in an emergency. Cut pressure in the line and every car will brake itself. Perhaps they meant situations involving hills, not uncommon for ore trains heading from mines.

A 30,000 ton ore train in Brazil will take about that long to stop, due to the nature of that weight strung out over 2.5 miles of distance.

That said, I think an emergency stop (air loss) would stop it faster.