An Example of how PTC will affect Commuter Rail Schedules

Amtrak Unlimited Discussion Forum

Help Support Amtrak Unlimited Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Rover

Conductor
Joined
May 13, 2015
Messages
1,493
Location
N. Texas
New Rock Island Line schedule finalized to meet demands of Positive Train Control


https://metrarail.com/about-metra/newsroom/new-rock-island-line-schedule-finalized-meet-demands-positive-train-control

To handle as many passengers as it does during the morning rush period, Metra must quickly turn trains around at downtown stations and send them back out to make more inbound trips. The same applies to the evening rush period, as trains complete their trips to the suburbs and turn back to pick up more customers downtown. Metra calls this process “flipping” a train, and it will take longer because of PTC.
 
To flip a train, the engineer must move from the cab car to the locomotive or vice versa, and the crew must clear the train, perform a brake test and conduct a job briefing. With the added task of initializing the PTC system, these “flips” are expected to take more than 10 minutes, so the schedule of about a dozen trains were adjusted, and those changes, in turn, affected other trains on the schedule. A video explaining the changes can be found at metrarail.com/PTC.
 
daybeers said:
Why does the system take so long to initialize?
I am not sure why I-ETMS requires a whole huge database to be downloaded each time it is initialized. Someone who knows more about the inards of I-ETMS may be able to help.

It may have something to do with the fact that all the information that the engine picks up on the fly from track mounted transponders in something like ACSES, has to be downloaded up front in I-ETMS. But I am not sure.
 
I-ETMS is so terrible.  It's just embarassing that the US couldn't adopt ETCS/ERTMS.  Oh well, that's what we get for living in an underdeveloped country.
 
I remember reading somewhere that within the yards (IIRC Metra specific, but could be wrong) there is a different system than PTC in use?

Metra doesn't have unlimited funds and probably, as proscribed by law, went with a low bidder, but I don't know how they wrote the RFP/specs either.
 
I-ETMS is so terrible.  It's just embarassing that the US couldn't adopt ETCS/ERTMS.  Oh well, that's what we get for living in an underdeveloped country.
I'm a noob, so can someone roughly explain the difference between these, and why the U.S. had to adopt I-ETMS? 
 
Why does the system take so long to initialize?


I am not sure why I-ETMS requires a whole huge database to be downloaded each time it is initialized. Someone who knows more about the inards of I-ETMS may be able to help.

It may have something to do with the fact that all the information that the engine pucks up on the fly from track mounted transponders in something like ACSES, has to be downloaded up front in I-ETMS. But I am not sure.
Long story short. Something like ACSES is a generic control system tailored to a type a train while I-ETMS is specific to your particular train. Therefore, everything about your train and crew has to be entered. Then, the appropriate information is downloaded to the system.
 
Last edited by a moderator:
Yup. It is geared more towards handling freight trains with varying characteristics rather than standard consist and braking characteristics passenger trains. No one in their right mind would use it on a primarily suburban passenger service route. Of course US has a vanishingly small number of those, and yet People's Republic of California went with I-ETMS on all its primarily suburban routes. It just goes to support my hypothesis that in many parts of the US passenger service is run mostly as a hobby and not as a serious enterprise. [emoji6] And that is why no one bothers to seriously question outrageous costs of building and operation, and do something about it, other than raise fares and cut back service.

There is a reason that Brightline chose to use E-ATC and not I-ETMS. The fancy features of the latter are unnecessary for its operations and apparently even for the uniform operating characteristics freight trains that FECR operates.

It is not unusual for a suburban EMU to be turned in 5 minutes elsewhere in the world and in principle possible, even in the Northeast. But not so in the rest of the US, where they are happy to run passenger railroad like it is 1950s in Iowa, minus the passenger facilities. [emoji1]
 
Last edited by a moderator:
I'm a noob, so can someone roughly explain the difference between these, and why the U.S. had to adopt I-ETMS? 
Under normal circumstances being one of the last parties to implement a technology based upgrade allows you to enjoy the fastest and cheapest solution that prevailed over all others, but here in the US we eschew anything that could be construed as efficient or cooperative, so the first item on our invoice is a reinvented wheel with square dimensions at twice the usual price.
 
Last edited by a moderator:
VRE is taking a pounding, particularly at AF, interlocking where NS and CSX meet. Turnaround time has also increased.

Things have improved but it is still a work in progress.

https://wtop.com/dc-transit/2019/05...ders-safety-system-related-delays-are-easing/

Every day for the last month, delay after delay has left many Virginia Railway Express riders frustrated. But the agency is confident it has now worked out most of the kinks with a new safety system.

“We think we’ve gotten over the hump of the worst of it,” said Joe Swartz, VRE chief of staff.

The consistent delays have been tied to crews getting used to positive train control, or PTC, systems, which are meant to automatically prevent or reduce the damage from collisions between trains, and to automatically slow down trains that are going at an unsafe speed on a curve or near workers.

That implementation has caused slowdowns for Manassas Line trains as they moved between tracks owned by Norfolk Southern and tracks owned by CSX; incorrect slower speed limits in the system; and an unexpectedly long process to turn trains around.

VRE expected the reinitialization of the system to take two or three minutes, but it initially took about 10 minutes, causing rippling delays.
 
VRE is taking a pounding, particularly at AF, interlocking where NS and CSX meet. Turnaround time has also increased.

Things have improved but it is still a work in progress.

https://wtop.com/dc-transit/2019/05...ders-safety-system-related-delays-are-easing/

Sadly this is part of bringing something new online. No matter what every Railroad is going to have teething issues with PTC. It’s not uncommon to hear of trains on the Reading Line in the NS Harrisburg Division to go without the PTC just cause they are still working out bugs. During my time at Septa I was working a train to Norristown, we were crossing over at 16th Street Junction from the main to the Norristown Line and the PTC kept dumping the train. We couldn’t get above 5 mph. As soon as the train hit 6 mph whoosh. Air would dump. Eventually they told us to Cutout the PTC. Septa uses a different version of Amtrak’s ACSES. So it’s transponder based.
 
Back
Top