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Heads or tails

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Posted by BaltACD on Monday, May 4, 2020 6:37 AM

blue streak 1
How many different remote units can be operated separately from the front ?  Is it the same for for all RRs and their various equipment or is it different ?  Have wondered that if you have say 2 units on the back if each unit was run separately from the front and are not connected with the MU cable?  That might be important especially if each unit was low on fuel ?  Crazy I know and probably not allowed by RR rules ?

My understanding, and I am not a engineer, is that the Engineer from the lead consist can control up to 4 additional engine consists place through out the train.

Each engine consist can be one or more locmotives.  Each carrier has their own rules and special instructions about where to locate the remote consist(s) in a train.

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Posted by blue streak 1 on Sunday, May 3, 2020 10:32 PM

How many different remote units can be operated separately from the front ?  Is it the same for for all RRs and their various equipment or is it different ?  Have wondered that if you have say 2 units on the back if each unit was run separately from the front and are not connected with the MU cable?  That might be important especially if each unit was low on fuel ?  Crazy I know and probably not allowed by RR rules ?

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Posted by BaltACD on Monday, April 20, 2020 9:36 PM

Murphy Siding
 
BaltACD 
Murphy Siding 
jeffhergert

If it's a 1 x 2 configuration the head end will feel a lot more slack action unless the DPs are run separately ('fence' up) from the head end.  The head end doesn't have enough power to 'run away' from the back end pushing through small sags in synchoronous operation.

Jeff   

Does fence up mean the front and back units are being operated seperately? Wouldn't that take a magician to get that right on an even slightly rail line?

The thing to remember about rail lines and their operation - their physical characteristics don't change from trip to trip - the grades, the dips, the sags, the speed restrictions are all in the same place that they were yestrday.

Engineers operate the line trip after trip and learn 'tricks of the trade' from time to time to apply to future trips - where to apply power, where to apply brakes, where to use stretch braking (If allowed), where slack may need to be bunched, where slack needs to stretched, when to raise or lower the fence when operating with DPU.  The engineer knows the 'feel' of his train - when it feels right, and when it doesn't.  The feel developed from many, many trips over the line with many kinds of trains - merchandise, intermodal, bare tables, loaded tank trains, empty tank trains, loaded grain, coal ore and other bulk commodity trains - running with Clear signals, running on Approach signals, running on Restricted Proceed signals, getting a temporary slow order at a specific point that is normally track speed and figuring out where to brake to be in compliance without slowing too soon or too late.

From his experience, a Engineer knows what his train 'should' feel like at every significant location on his territory - in handling his train the Engineer has his mind miles ahead in planning the operation of the train. 

That all makes good sense, but I'm thinking. What happens if this week's train is 96 cars and last week's train was 100? Does having the trailing engines a couple hundred feet "off" make a difference?

The Engineer will apply 'Kentucky Windage' to his normal train handling procedures for how he 'feels' the train is handling.  Every foot of the way the Engineer has a 'handling picture' of what the train should feel line in line with 'the facts' that are presented about the train's consist; he keeps comparing the actual feel of the train to his control inputs to that 'handling picture' he has in his mind.  The basic train operating plan for a train will be the same most all the time - it will be adjusted due to the specific train handling characteristics that the engineer is feeling this trip.  It is possible that the 100 car train will have better braking response than a shorter train - for the most mart 4 or 5 cars are insignificant.

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Posted by Murphy Siding on Monday, April 20, 2020 8:33 PM

BaltACD

 

 
Murphy Siding
 
jeffhergert

If it's a 1 x 2 configuration the head end will feel a lot more slack action unless the DPs are run separately ('fence' up) from the head end.  The head end doesn't have enough power to 'run away' from the back end pushing through small sags in synchoronous operation.

Jeff   

Does fence up mean the front and back units are being operated seperately? Wouldn't that take a magician to get that right on an even slightly rail line?

 

The thing to remember about rail lines and their operation - their physical characteristics don't change from trip to trip - the grades, the dips, the sags, the speed restrictions are all in the same place that they were yestrday.

Engineers operate the line trip after trip and learn 'tricks of the trade' from time to time to apply to future trips - where to apply power, where to apply brakes, where to use stretch braking (If allowed), where slack may need to be bunched, where slack needs to stretched, when to raise or lower the fence when operating with DPU.  The engineer knows the 'feel' of his train - when it feels right, and when it doesn't.  The feel developed from many, many trips over the line with many kinds of trains - merchandise, intermodal, bare tables, loaded tank trains, empty tank trains, loaded grain, coal ore and other bulk commodity trains - running with Clear signals, running on Approach signals, running on Restricted Proceed signals, getting a temporary slow order at a specific point that is normally track speed and figuring out where to brake to be in compliance without slowing too soon or too late.

From his experience, a Engineer knows what his train 'should' feel like at every significant location on his territory - in handling his train the Engineer has his mind miles ahead in planning the operation of the train.

 

That all makes good sense, but I'm thinking. What happens if this week's train is 96 cars and last week's train was 100? Does having the trailing engines a couple hundred feet "off" make a difference?

Thanks to Chris / CopCarSS for my avatar.

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Posted by SD70Dude on Monday, April 20, 2020 7:47 PM

BaltACD
SD70Dude
guetem1

largely, it can be a matter of convenience, sone grain facilities aren't conducive to hosteling power, so the train may have gone in 2x1 and will come out 1 x 2 because there is nowhere to turn the consist, sometimes it can be a junction that only faces in one direction so pulling a 1x2 train past a switch, and proceeds through the switch and voila, you now have a 2 x 1 train running up the branch 

We have some places like that too.

CN's operating instructions do not allow a remote consist to have more powered axles than the lead consist.  So if you see one of our trains running in this fashion one of the remote units must be isolated, or it may have died enroute and is being left in the train until it gets to a shop.

Or the train could simply be backing up, which is a common occurrence in some places and situations.

Is it possible for a Engineer operating from a single unit on the head end to isolate one of the two units on the rear, without physically going to the two units and isolating one of them?

No.  You have to go in the cab and turn the switch.  The few trains that end up running like this will be empty, so the extra power of the third unit is not needed, and it will be isolated at the start of the trip when the train is built in that manner.

The entire remote consist can be isolated, and when operating with multiple remote consists each one can be isolated independently of the others.

Greetings from Alberta

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Posted by BaltACD on Monday, April 20, 2020 7:06 PM

SD70Dude
 
guetem1

largely, it can be a matter of convenience, sone grain facilities aren't conducive to hosteling power, so the train may have gone in 2x1 and will come out 1 x 2 because there is nowhere to turn the consist, sometimes it can be a junction that only faces in one direction so pulling a 1x2 train past a switch, and proceeds through the switch and voila, you now have a 2 x 1 train running up the branch 

We have some places like that too.

CN's operating instructions do not allow a remote consist to have more powered axles than the lead consist.  So if you see one of our trains running in this fashion one of the remote units must be isolated, or it may have died enroute and is being left in the train until it gets to a shop.

Or the train could simply be backing up, which is a common occurrence in some places and situations.

Is it possible for a Engineer operating from a single unit on the head end to isolate one of the two units on the rear, without physically going to the two units and isolating one of them?

Never too old to have a happy childhood!

              

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Posted by SD70Dude on Monday, April 20, 2020 6:40 PM

guetem1

largely, it can be a matter of convenience, sone grain facilities aren't conducive to hosteling power, so the train may have gone in 2x1 and will come out 1 x 2 because there is nowhere to turn the consist, sometimes it can be a junction that only faces in one direction so pulling a 1x2 train past a switch, and proceeds through the switch and voila, you now have a 2 x 1 train running up the branch

We have some places like that too.

CN's operating instructions do not allow a remote consist to have more powered axles than the lead consist.  So if you see one of our trains running in this fashion one of the remote units must be isolated, or it may have died enroute and is being left in the train until it gets to a shop.

Or the train could simply be backing up, which is a common occurrence in some places and situations.

Greetings from Alberta

-an Articulate Malcontent

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Posted by guetem1 on Monday, April 20, 2020 5:07 PM

largely, it can be a matter of convenience, sone grain facilities aren't conducive to hosteling power, so the train may have gone in 2x1 and will come out 1 x 2 because there is nowhere to turn the consist, sometimes it can be a junction that only faces in one direction so pulling a 1x2 train past a switch, and proceeds through the switch and voila, you now have a 2 x 1 train running up the branch

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Posted by BaltACD on Monday, April 20, 2020 3:03 PM

Murphy Siding
 
jeffhergert

If it's a 1 x 2 configuration the head end will feel a lot more slack action unless the DPs are run separately ('fence' up) from the head end.  The head end doesn't have enough power to 'run away' from the back end pushing through small sags in synchoronous operation.

Jeff   

Does fence up mean the front and back units are being operated seperately? Wouldn't that take a magician to get that right on an even slightly rail line?

The thing to remember about rail lines and their operation - their physical characteristics don't change from trip to trip - the grades, the dips, the sags, the speed restrictions are all in the same place that they were yestrday.

Engineers operate the line trip after trip and learn 'tricks of the trade' from time to time to apply to future trips - where to apply power, where to apply brakes, where to use stretch braking (If allowed), where slack may need to be bunched, where slack needs to stretched, when to raise or lower the fence when operating with DPU.  The engineer knows the 'feel' of his train - when it feels right, and when it doesn't.  The feel developed from many, many trips over the line with many kinds of trains - merchandise, intermodal, bare tables, loaded tank trains, empty tank trains, loaded grain, coal ore and other bulk commodity trains - running with Clear signals, running on Approach signals, running on Restricted Proceed signals, getting a temporary slow order at a specific point that is normally track speed and figuring out where to brake to be in compliance without slowing too soon or too late.

From his experience, a Engineer knows what his train 'should' feel like at every significant location on his territory - in handling his train the Engineer has his mind miles ahead in planning the operation of the train.

Never too old to have a happy childhood!

              

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Posted by Murphy Siding on Monday, April 20, 2020 2:19 PM

samfp1943
 
Murphy Siding

      In a loaded unit train of grain with 2 locomotives on one end and 1 locomotive on the other end, does it matter if the head end has 1 or 2 locomotives? I just saw one come by with the single up front. If it means anything, track around these parts is pretty flat. 

 

 

  Norris: I'll leave operational mechanics up to the pros, like Jeff H.

In this area, { strictly, a subjective observation!]  the BNSF seems to operate, in the 1x2 configuratons, mostly, [on the all grain hopper configurations].

    When they have a single leading unit, and a couple of units in rear DPU on the other end; the trains seems to be an empty, returning to its reloading location,[ reverse route?].  The feed supplemt trains { Jeff H. has noted them in previous Forum entries}; on their return route(?) ;lately, thru here, they seem to be a combination of two empty, return trains(?); a guess is, they are 10K ft., plus in length(?).

I do not see too many on the OKT line going South in this area. I have no idea what common practice is on UP.   They seem to march to their own 'music'.. Whistling

 

 

These were loaded grain cars. I know that from my recent education on the subject, the sound of the cars, and knowing where they originated.

Thanks to Chris / CopCarSS for my avatar.

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Posted by Murphy Siding on Monday, April 20, 2020 2:17 PM

jeffhergert

If it's a 1 x 2 configuration the head end will feel a lot more slack action unless the DPs are run separately ('fence' up) from the head end.  The head end doesn't have enough power to 'run away' from the back end pushing through small sags in synchoronous operation.

Jeff  

 

 

Does fence up mean the front and back units are being operated seperately? Wouldn't that take a magician to get that right on an even slightly rail line?

Thanks to Chris / CopCarSS for my avatar.

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Posted by samfp1943 on Monday, April 20, 2020 10:07 AM

Murphy Siding

      In a loaded unit train of grain with 2 locomotives on one end and 1 locomotive on the other end, does it matter if the head end has 1 or 2 locomotives? I just saw one come by with the single up front. If it means anything, track around these parts is pretty flat. 

  Norris: I'll leave operational mechanics up to the pros, like Jeff H.

In this area, { strictly, a subjective observation!]  the BNSF seems to operate, in the 1x2 configuratons, mostly, [on the all grain hopper configurations].

    When they have a single leading unit, and a couple of units in rear DPU on the other end; the trains seems to be an empty, returning to its reloading location,[ reverse route?].  The feed supplemt trains { Jeff H. has noted them in previous Forum entries}; on their return route(?) ;lately, thru here, they seem to be a combination of two empty, return trains(?); a guess is, they are 10K ft., plus in length(?).

I do not see too many on the OKT line going South in this area. I have no idea what common practice is on UP.   They seem to march to their own 'music'.. Whistling

 

 

 


 

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Posted by jeffhergert on Sunday, April 19, 2020 6:44 PM

If it's a 1 x 2 configuration the head end will feel a lot more slack action unless the DPs are run separately ('fence' up) from the head end.  The head end doesn't have enough power to 'run away' from the back end pushing through small sags in synchoronous operation.

Jeff  

 

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Heads or tails
Posted by Murphy Siding on Sunday, April 19, 2020 2:58 PM

      In a loaded unit train of grain with 2 locomotives on one end and 1 locomotive on the other end, does it matter if the head end has 1 or 2 locomotives? I just saw one come by with the single up front. If it means anything, track around these parts is pretty flat. 

Thanks to Chris / CopCarSS for my avatar.

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