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

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

#71

Post by ThrustVectoring »

btilly wrote: post #58
dredmorbius wrote: post #11

Earlier quoted context omitted.

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. Which is exactly why bicycles are so fond of rolling through stop signs. When you're riding one, it is obvious to you that going from 20 mph down to 10, then back up to 20 is reasonably safe and only takes half the effort as going from 20 mph down to 0…

It takes 3/4 of the effort - kinetic energy is proportional to the square of speed.

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

#72

Post by gsnedders »

ant6n wrote: post #66
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"

How about using some sort of advance signal?

There are repeater signals for this purpose, see http://railsigns.uk/sect7page1/sect7page1.html

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

#73

Post by ComradeTaco »

kposehn wrote: post #19
TylerE wrote: post #12

Earlier quoted context omitted.

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…

As a random piece of trivia, in cab signaling was pioneered in the 1920's and implemented commercially by Pennsylvania Railroad the 1930's while upgrading their main line between New York City and Washington D.C. You can see in this photo that the engineer had one indicator that would light up for each signal aspect: https://i.pinimg.com/originals/31/85/83/3185833fba11b79498ff...

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

#74

Post by gsnedders »

kposehn wrote: post #19
TylerE wrote: post #12

Earlier quoted context omitted.

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…

Realistically, in the UK, it's going to be ETCS with balises: all new build stock at this point either has ETCS in-cab signalling fitted, or is designed for its fitment.

That said, the rollout of the infrastructure side of ETCS is somewhat delayed, but it is happening in places (Thameslink is ETCS Level 2 with conventional signal overlay, albeit with shorter blocks in ETCS; Crossrail is ETCS Level 2 with no overlay).

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

#75

Post by gsnedders »

grkvlt wrote: post #68
code_duck wrote: post #23

Earlier quoted context omitted.

Car drivers tend to underestimate the amount of space it takes for a semi to stop. Heck, every time I load up my car or attach a trailer, it takes time to become accustomed to the decreased braking performance. Drivers likely could not give an accurate estimation for how many feet it takes to do anything on the road, such as come to a stop in an SUV going 50. Given the extreme mass of a cargo train, I wouldn't be sur…

> how many feet it takes to do anything on the road, such as come to a stop in an SUV going 50 Isn't knowledge of stopping distances for vehicles at various speeds and different road surface conditions a requirement for obtaining a driving license? (At least, in the UK I believe it is, and I think the Highway Code tables probably over-estimate these distances for safety purposes)

The Highway Code tables are based on an average family car in the 1960s (IIRC) when the tables were first introduced. They're ridiculously long distances for modern cars, though AIUI the "thinking time" part is nowadays thought to be too low.

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

#76

Post by grkvlt »

gsnedders wrote: post #75
grkvlt wrote: post #68

Earlier quoted context omitted.

> how many feet it takes to do anything on the road, such as come to a stop in an SUV going 50 Isn't knowledge of stopping distances for vehicles at various speeds and different road surface conditions a requirement for obtaining a driving license? (At least, in the UK I believe it is, and I think the Highway Code tables probably over-estimate these distances for safety purposes)

The Highway Code tables are based on an average family car in the 1960s (IIRC) when the tables were first introduced. They're ridiculously long distances for modern cars, though AIUI the "thinking time" part is nowadays thought to be too low.

Still, that's not a bad thing, per se. If we underestimate based on a vaguely remembered overestimated value from the highway code based on 1960s cars, then the effects cancel out and we're basically correct for modern vehicles?

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

#77

Post by code_duck »

grkvlt wrote: post #68
code_duck wrote: post #23

Earlier quoted context omitted.

Car drivers tend to underestimate the amount of space it takes for a semi to stop. Heck, every time I load up my car or attach a trailer, it takes time to become accustomed to the decreased braking performance. Drivers likely could not give an accurate estimation for how many feet it takes to do anything on the road, such as come to a stop in an SUV going 50. Given the extreme mass of a cargo train, I wouldn't be sur…

> how many feet it takes to do anything on the road, such as come to a stop in an SUV going 50 Isn't knowledge of stopping distances for vehicles at various speeds and different road surface conditions a requirement for obtaining a driving license? (At least, in the UK I believe it is, and I think the Highway Code tables probably over-estimate these distances for safety purposes)

Yes, but I don't think it requires or correlates to real understanding of what the distances are. I doubt that people understand how it varies with speed, or what that number of feet really looks like on the road. The process I have experienced is I read what a theoretical distance is in the booklet the state gave me for the exam, and then select their indicated answer on a multiple-choice test.

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

#78

Post by gsnedders »

grkvlt wrote: post #76
gsnedders wrote: post #75

Earlier quoted context omitted.

The Highway Code tables are based on an average family car in the 1960s (IIRC) when the tables were first introduced. They're ridiculously long distances for modern cars, though AIUI the "thinking time" part is nowadays thought to be too low.

Still, that's not a bad thing, per se. If we underestimate based on a vaguely remembered overestimated value from the highway code based on 1960s cars, then the effects cancel out and we're basically correct for modern vehicles?

I /think/ I recall seeing something that claimed with longer reaction times it actually ended up worse overall.

That said, I think often the bigger problem is people not realising especially in more unusual conditions (like snow in much of Britain) quite how much longer braking distances become.

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

#79

Post by hexane360 »

btilly wrote: post #58
dredmorbius wrote: post #11

Earlier quoted context omitted.

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. Which is exactly why bicycles are so fond of rolling through stop signs. When you're riding one, it is obvious to you that going from 20 mph down to 10, then back up to 20 is reasonably safe and only takes half the effort as going from 20 mph down to 0…

Not to mention that a person pedaling from a standstill has a lot less power output than a person pedaling an already moving bike.

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

#80

Post by hexane360 »

dmckeon wrote: post #15

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…

I loved those videos too, but it was pointed out to me how much blame they put on the employee for unsafe working conditions. Safety isn't just about telling your employees to be safe and punishing them when they aren't.
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