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How is the number of cars per train determined for commuter rail

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How is the number of cars per train determined for commuter rail
Posted by kittysharyo on Friday, August 9, 2024 9:45 PM

I live close to work, but I often take commuter rail for adventures, which means typically not in rush hour even on weekdays when I'm on vacation. I often find the trains really empty, like sometimes only 5 passengers in a bilevel car that can seat over 100 and once I was the only person in a cab car besides the engineer and conductor (the Rotem cab car has 173 seats). I thought maybe it's just a Metrolink (LA metro area) thing and LA transit isn't splendid. In LA, the most occupied Metrolink train I've been on was on the San Bernardino line from San Bernardino to LA Union Station on a weekday evening and the car I was in was only about 1/3 occupied. I visited Chicago in the summer and took the Metra a lot for adventures; it was also quite empty off peak so it was probably not just LA. I feel like, isn't that a huge waste of energy, like the fuel to start and accelerate the train and get it up hill and the AC for all the empty space? How do they determine how many cars to use per train?

OK, maybe it's empty because it's off peak, so I looked up some data. For LA Metrolink, the San Bernardino line is the busiest from January to March 2024 (data here: https://metrolinktrains.com/about/agency/facts--numbers/), with on average about 207 passengers per train, but the average is misleading because peak hour trains would be more occupied. So I guess say 400 passengers per train at the very peak time and segment, which makes the typical 4 or 5 car consist of Metrolink reasonable. From a similar calculation, Caltrain's 5 car consist is also reasonable. Probably Metrolink determines how many cars to use based on the very peak time and segment and adds some more seats due to variability in the number of passengers and to make passengers more comfortable. Is that correct? But why don't they drop off the extra cars for off peak? More work than turning around and they don't turn around hence the cab car? Meanwhile other much less busy lines (e.g. Riverside line with 115 passengers per train on average on weekdays Jan to March 2024) don't have shorter trains but less frequent services which might have caused lower ridership.

Chicago Metra has more detailed data (https://metra.com/dashboard) on ridership of each train through the day for each line and direction. Some of the lines get >100 passengers per car much of the day during weekdays. But the problem comes when some lines, like the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. I don't think the transportation industry in general is that concerned about covid social distancing in 2024, since many Amtrak trains are completely full, so are flights where passengers are packed even more tightly. Then why don't Metra and other agencies use fewer cars per train for lines that clearly have low ridership and low occupancy even at the very peak?

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Posted by BaltACD on Monday, August 12, 2024 10:51 AM

kittysharyo
I live close to work, but I often take commuter rail for adventures, which means typically not in rush hour even on weekdays when I'm on vacation. I often find the trains really empty, like sometimes only 5 passengers in a bilevel car that can seat over 100 and once I was the only person in a cab car besides the engineer and conductor (the Rotem cab car has 173 seats). I thought maybe it's just a Metrolink (LA metro area) thing and LA transit isn't splendid. In LA, the most occupied Metrolink train I've been on was on the San Bernardino line from San Bernardino to LA Union Station on a weekday evening and the car I was in was only about 1/3 occupied. I visited Chicago in the summer and took the Metra a lot for adventures; it was also quite empty off peak so it was probably not just LA. I feel like, isn't that a huge waste of energy, like the fuel to start and accelerate the train and get it up hill and the AC for all the empty space? How do they determine how many cars to use per train?

OK, maybe it's empty because it's off peak, so I looked up some data. For LA Metrolink, the San Bernardino line is the busiest from January to March 2024 (data here: https://metrolinktrains.com/about/agency/facts--numbers/), with on average about 207 passengers per train, but the average is misleading because peak hour trains would be more occupied. So I guess say 400 passengers per train at the very peak time and segment, which makes the typical 4 or 5 car consist of Metrolink reasonable. From a similar calculation, Caltrain's 5 car consist is also reasonable. Probably Metrolink determines how many cars to use based on the very peak time and segment and adds some more seats due to variability in the number of passengers and to make passengers more comfortable. Is that correct? But why don't they drop off the extra cars for off peak? More work than turning around and they don't turn around hence the cab car? Meanwhile other much less busy lines (e.g. Riverside line with 115 passengers per train on average on weekdays Jan to March 2024) don't have shorter trains but less frequent services which might have caused lower ridership.

Chicago Metra has more detailed data (https://metra.com/dashboard) on ridership of each train through the day for each line and direction. Some of the lines get >100 passengers per car much of the day during weekdays. But the problem comes when some lines, like the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. I don't think the transportation industry in general is that concerned about covid social distancing in 2024, since many Amtrak trains are completely full, so are flights where passengers are packed even more tightly. Then why don't Metra and other agencies use fewer cars per train for lines that clearly have low ridership and low occupancy even at the very peak?

It takes manpower and space to adjust the size of trains.  If you have a 8 car inbound train for the morning rush hour - most likely that train will either lay over for the afternoon rush hour, or it will go outbound in the morning still with 8 cars and very few passengers to it suburban destination, it will then make an 8 car train to the urban terminal again with few passengers to be in position for the afternoon rush hour where it will be full of pasengers.

The commuter operations I am most familiar with are MARC and VRE into and out of Washington DC.  All VRE trains operate into DC in the morning rush hours and return to Fredericksburg and Manassas during the afternoon rush hours.  MARC does likewise operating inbound to DC from Baltimore, Frederick and Martinsburg in the morning and outbound in the afternoon.

Never too old to have a happy childhood!

              

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Posted by CSSHEGEWISCH on Monday, August 12, 2024 12:03 PM

Balt is right.  While train size on Metra is no longer adjusted for lower ridership in the midday (CTA is the same way), not every car is open for service on the midday trains.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by MidlandMike on Monday, August 12, 2024 8:47 PM

kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers.

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train.

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Posted by BaltACD on Tuesday, August 13, 2024 8:15 AM

MidlandMike
 
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train.

I am surprised that those operating under the CN axle restrictions haven't taken CN to court to for forcing the secondary users to subject their operations to unsafe signal systems.

Never too old to have a happy childhood!

              

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Posted by CSSHEGEWISCH on Tuesday, August 13, 2024 1:08 PM

MidlandMike
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers.

 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train.

 
The electrified suburban lines, which are mostly separate from the parallel freight and passenger lines, are owned and operated by Metra.
The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by Overmod on Wednesday, August 14, 2024 7:05 PM

Many commuter services are length-limited first by platform length and then by adjacent grade crossings that are blocked by 'overhanging' power or cab cars.

The gains from operating shorter consists during the day are normally far outweighed by the cost of switching cars in and out of consists, particularly when there is a dedicated 'cab car' on the far end.  Subway and elevated operations with MU equipment can often 'afford' to run shorter trains in off-peak service, but there is far less 'economy' in doing this for heavy-rail off-peak service (compared to the alternative mentioned, which is to cut off lighting and A/C to some of the cars in an otherwise-fixed consist).

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Posted by JL Chicago on Thursday, September 12, 2024 3:53 PM

I remember reading in one of the Chicago papers about a decade or two back that Metra did a study and determined it was more costly to switch out cars than just haul the extra cars.  Fuel costs really are minimal although I always wondered if they fully accounted for all maintenance costs.  

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Posted by Flintlock76 on Tuesday, September 17, 2024 11:37 AM

While I make absolutely no claim of  being a transit expert just from watching videos of NJ Transit rail operations I've seen consists vary from four to eight cars per train although five or six seem to be typical.  I'm assuming consists are determined by passenger volume and train frequency on the various routes.  Interestingly whether the routes are electrified or diesel only doesn't seem to make a difference.  I've also noticed depending on time of day some cars are unoccupied, I'm assuming blocked off deliberately due to low patronage at that time of day .  

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Posted by n012944 on Thursday, September 19, 2024 9:46 AM

BaltACD

 

 
MidlandMike
 
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train.

 

I am surprised that those operating under the CN axle restrictions haven't taken CN to court to for forcing the secondary users to subject their operations to unsafe signal systems.

 

 

CN's argument to that would be, it isn't unsafe, if you follow our rules.  Amtrak is free to run a reduced consist, less than the axle restrictions, it will just be at a slower pace.

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Posted by BaltACD on Thursday, September 19, 2024 11:54 AM

n012944
 
BaltACD 
MidlandMike 
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train. 

I am surprised that those operating under the CN axle restrictions haven't taken CN to court to for forcing the secondary users to subject their operations to unsafe signal systems. 

CN's argument to that would be, it isn't unsafe, if you follow our rules.  Amtrak is free to run a reduced consist, less than the axle restrictions, it will just be at a slower pace.

Amtrak should reduce their payments to CN account of a UNSAFE signal system.  A signal system in a territory where rust rail conditions are not an issue requiring 7 cars to 'insure' it's activation is unsafe on its face.

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Posted by Overmod on Thursday, September 19, 2024 2:16 PM

While on the subject of what became Metra Electric: I saw an excerpt from a video that appeared to show many of the steel IC MUs coupled into one long line 'over the weekend' which suggested that trains might have been sequentially 'uncoupled to length' as consists were dispatched the next regular morning...

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Posted by n012944 on Friday, September 20, 2024 10:11 AM

BaltACD

 

 
n012944
 
BaltACD 
MidlandMike 
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train. 

I am surprised that those operating under the CN axle restrictions haven't taken CN to court to for forcing the secondary users to subject their operations to unsafe signal systems. 

CN's argument to that would be, it isn't unsafe, if you follow our rules.  Amtrak is free to run a reduced consist, less than the axle restrictions, it will just be at a slower pace.

 

Amtrak should reduce their payments to CN account of a UNSAFE signal system.  A signal system in a territory where rust rail conditions are not an issue requiring 7 cars to 'insure' it's activation is unsafe on its face.

 

 

It isn't unsafe, and works just fine, if you follow the rules.  Less than 7 cars, 60 mph leading up to road crossings and things work fine.  Want to run 79mph?  Then 7 cars it is.  It is really no different than a single 4 axle locomotive being limited to 30 mph, and not allowing a train in behind that lite power, as the signal system might lose shunt.   It is safe, if you follow the rules to protect it.

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Posted by BaltACD on Wednesday, October 9, 2024 10:48 PM

n012944
 
BaltACD
n012944 
BaltACD 
MidlandMike 
kittysharyo
... the Electric line, get at most 50-70 passengers per car at the busiest and 80% of the time there're <50 per car. Each of the Highliner cars with commuter type seats can seat well over 100 passengers. 

Are these ex-IC lines still owned by CN.  They require a certain number of axels (32?) per train. 

I am surprised that those operating under the CN axle restrictions haven't taken CN to court to for forcing the secondary users to subject their operations to unsafe signal systems. 

CN's argument to that would be, it isn't unsafe, if you follow our rules.  Amtrak is free to run a reduced consist, less than the axle restrictions, it will just be at a slower pace. 

Amtrak should reduce their payments to CN account of a UNSAFE signal system.  A signal system in a territory where rust rail conditions are not an issue requiring 7 cars to 'insure' it's activation is unsafe on its face.

It isn't unsafe, and works just fine, if you follow the rules.  Less than 7 cars, 60 mph leading up to road crossings and things work fine.  Want to run 79mph?  Then 7 cars it is.  It is really no different than a single 4 axle locomotive being limited to 30 mph, and not allowing a train in behind that lite power, as the signal system might lose shunt.   It is safe, if you follow the rules to protect it.

Back in the  day when the 30 MPH restiction on single units was originated, it was because the relay based signal systems could not respond to circuit activations quickly enough.  Those systems were satisfactory over half a century ago for two units.  I guess Canadian relays are frozen in time as they have to translate the American electrical impulses into French and send them on to Ottawa to be translated into Canadian and then sent to New Orleans to be translated ino Cajun to activate the signal system.  

Never too old to have a happy childhood!

              

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