Does anyone think we will see 90 mph top speeds (track permitting) for more trains across the entire Amtrak system with the PTC mandate coming in December 2015, maybe just in flatter areas? I know crossing gates would have to be re-timed and freight RRs would have to agree, but other than that I do not see what else needs to be done. Thoughts.....
2015 PTC Mandate: Possibility of higher speeds across the system
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jis
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My guess is that the PTC mandate will be postponed beyond December 2015. But there will be considerable amount of route mileage that will be under PTC by then, and no Amtrak train will be running at any higher speed on any of those PTC routes by then, other than those where they already run at 90mph.
Welded rail, well maintained ballast and high quality wood or concrete ties is enough to safely support 90 mph speeds. Remember, the SWC used to go 90 over jointed rail!
jis
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Incidentally the following subs on BNSF already have operational PTC:
Illinois:
Mendota
California:
San Bernardino
Bakersfield
Mojave
Stockton
Needles
Of these, I believe Mendota, San Bernardino, Bakersfield, Stockton and Needles subs host Amtrak. I am unaware of whether Amtrak has any engines equipped to run under BNSF PTC yet. The BNSF rulebook says that any train equipped with PTC must use PTC in these subs, but all trains need not be equipped with PTC at present to travel on these subs.
In Amtrakland the situation is similar on NEC south as far as PTC goes. Of course Amtrak spells PTC as ACSES on the NEC and attached routes since all commuter agencies around the NEC like SEPTA, NJT, MNRR and LIRR plan to use some form of ACSES to meet the PTC mandate.
All Amtrak trains must run using ACSES where the track is so equipped and Amtrak trains are not allowed to depart origin with inoperative ACSES. However, other trains need not have ACSES operative to run on ACSES equipped tracks. It is sufficient for them to just have operating cab signals to operate at speeds upto 125mph. Above that ACSES is mandatory.
Illinois:
Mendota
California:
San Bernardino
Bakersfield
Mojave
Stockton
Needles
Of these, I believe Mendota, San Bernardino, Bakersfield, Stockton and Needles subs host Amtrak. I am unaware of whether Amtrak has any engines equipped to run under BNSF PTC yet. The BNSF rulebook says that any train equipped with PTC must use PTC in these subs, but all trains need not be equipped with PTC at present to travel on these subs.
In Amtrakland the situation is similar on NEC south as far as PTC goes. Of course Amtrak spells PTC as ACSES on the NEC and attached routes since all commuter agencies around the NEC like SEPTA, NJT, MNRR and LIRR plan to use some form of ACSES to meet the PTC mandate.
All Amtrak trains must run using ACSES where the track is so equipped and Amtrak trains are not allowed to depart origin with inoperative ACSES. However, other trains need not have ACSES operative to run on ACSES equipped tracks. It is sufficient for them to just have operating cab signals to operate at speeds upto 125mph. Above that ACSES is mandatory.
I think we may see some cases of trains moving from 79 mph to 90 mph where the only limitation has really been PTC, but there are plenty of places where that isn't the case and track condition is a major factor. I do think, for example, that in VA you might see it on the Peninsula subdivision...but you likely won't see it on the RF&P.
One caveat to this: We might see 90 mph operation, but it might not affect the timetable...I can see the freights allowing the use of 90 mph speeds to facilitate better timekeeping (i.e. getting a train back in slot) but not actually letting Amtrak compensate much in the timetable.
One caveat to this: We might see 90 mph operation, but it might not affect the timetable...I can see the freights allowing the use of 90 mph speeds to facilitate better timekeeping (i.e. getting a train back in slot) but not actually letting Amtrak compensate much in the timetable.
Swadian Hardcore
Engineer
This is a major problem with the restrictive Amtrak operations. A lot of tracks get upgrades but time savings are still trivial when lots of the extra speed gets commited to padding. A 14% speed increase should result in at least a 10% time saving.
Acceleration time. Extrapolating from Fairmount DMU study, there's a .03 mphps decrease in acceleration for a diesel push-pull train for every 5mph of speed starting with the acceleration from 25mph to 30mph. So to accelerate from 80mph to 90mph would take 163 seconds and take 20,458 feet. In the meantime, a 79mph train has covered 18,891.7 for a net gain of only 1,566.8 feet or 13.5 seconds after 3.87 miles of 90mph running. For every ten miles thereafter, you'll gain 50 seconds of time, but you'll probably have stops around that 15 mile mark, if not earlier (unless you're a long distance training running out in the middle of nowhere in which case nobody really cares whether or not you're appreciably faster). So basically you cut a minute from the schedule. It's really not worth all that much.
If you want to speed things up, what you want to do is minimize slow periods and sections (because they also have deceleration penalties) and raise your ability to accelerate quickly so you can spend more time at high speed. Nothing beats electrification for that, especially when combined with the use of distributed traction. Refer back to the Fairmount DMU study. A diesel push-pull train takes 166 seconds and 8,388 feet to accelerate to 60mph. The GPS logged actual journey time and distance of a BR Class 395 doing the same is 32 seconds and 1,498 feet. Assuming no further acceleration and no deceleration, the 395 passes an arbitrary 5 mile marker after 315 seconds while the diesel push pull train does so almost a minute later after 370.7 seconds. The more common your stops or slow zones, the greater the benefit of electrification's higher acceleration and the lower the advantage of a higher running speed (in fact, it would take 8.13 miles and 7.73 minutes for that diesel push-pull to accelerate to 90mph in the first place which makes such an upgrade nearly useless for many intercity runs; by contrast, the 395 does it in 57 seconds and 4,320 feet, before the diesel push-pull has even reached 30mph).
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Nathanael
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I would expect to see a lot of trains speed up from 79 mph to 80 mph. Not very exciting, I know, but every little bit helps...
Nothing will go up to 90 mph unless there is already Class 5 track (used for freight speed limits above 60 mph, or sometimes just for very heavy traffic loads). Others would know what tracks are already Class 5. (Anyone have a list?)
Even on those routes which are already class 5 track and get PTC, I wouldn't expect a lot of 90 mph running as a matter of scheduling (except in areas where the track is owned by passenger operators or states) because the freight railroads like to keep the Amtraks running at speeds as close as possible to the freight speeds to simplify dispatching. I can certainly see 90 mph being permitted for "catching up", however, when Amtrak trains get delayed at a station or whatever. I could see it being used for scheduling if it helped make the slots "come out right". ("Amtrak runs at 90 mph, then stops at this station for 10 minutes, then runs at 90 mph, then stops at this station for 10 minutes, averaging 50 mph, the same speed as the stack train behind it.")
For 90 mph, grade crossings might need retiming, but they don't need any major improvements.
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Nathanael
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Poking around, it appears that large portions of UP's mainlines and BNSF's mainlines are maintained to class 5 standards, with 70 mph + freight speed limits. Also the CN (IC) route which the City of New Orleans runs on. It sounds, from what I've been able to find, like very little is maintained to class 5 standards east of the Mississippi, except on "passenger-owned" track.
Accordingly my *educated guess* is that after PTC installation, 90 mph running will be used on parts of the UP, BNSF, and CN lines; but I'm guessing it will in most places be used only to "keep the train in slot" so that it runs at the same average speed as the freights (remembering that the passenger train is slowed by more station stops). That alone could be quite valuable; schedule adherence matters a lot. On routes like the Pacific Surfliner, where the track is already class 5, most of it is owned by passenger operators, and the route is full of passenger trains with relatively few freights, 90 mph might be used more extensively.
Accordingly my *educated guess* is that after PTC installation, 90 mph running will be used on parts of the UP, BNSF, and CN lines; but I'm guessing it will in most places be used only to "keep the train in slot" so that it runs at the same average speed as the freights (remembering that the passenger train is slowed by more station stops). That alone could be quite valuable; schedule adherence matters a lot. On routes like the Pacific Surfliner, where the track is already class 5, most of it is owned by passenger operators, and the route is full of passenger trains with relatively few freights, 90 mph might be used more extensively.
Swadian Hardcore
Engineer
Great analysis. I see what you mean. I have felt that acceleration on Amtrak trains is often very slow. I do enjoy a nice quick burst of speed which seems very rare on Amtrak. Too bad, I guess it would be quite pointless to get lots of 90 mph track if you can't use it well. Most MUs are uncomfortable for long trips.
I think the Class 395 was designed as a high-speed train. It also has electric power. Some British railfans have said the old InterCity 125 is more comfy than MUs. Acceleration isn't as great because it's got a separate locomotive running diesel.
It's a high speed commuter train actually. Go figure. As for comfort on MU vs push-pull, I suspect that has rather more to do with how the seats are set up as most MUs, so far, have been for commuter service (though the Shinkansens, notably, have always used distributed traction). The rest of the world is moving towards MUs for all passenger service however, which reinforces my theory regarding comfort.
jis
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One of the best selling HSR sets - the Siemens Valero - is distributed power EMU and I am told that in many of its incarnations from ICE to Saipan in Russia it is rather comfortable inside.
Amtrak George
Lead Service Attendant
I would guess that some lines may agree to raise the top speed from 79 to 80. Other than that, on lines Amtrak owns, PTC could create the possibility of higher speeds for track that would handle it.
Looking at things from the freight railroads' point of view, I don't see them raising the speed limit for passenger trains without the following:
1. A new contract with Amtrak in which Amtrak pays for the track to be put in shape and kept in shape for higher speeds.
2. Massive improvements in grade crossing protection including changing the timing of crossing signals.
3. Line relocations in many cases to reduce curvature and other impediments to speed (even the CN line through the Mississippi Delta has some speed restrictions on curves!)
Looking at things from the freight railroads' point of view, I don't see them raising the speed limit for passenger trains without the following:
1. A new contract with Amtrak in which Amtrak pays for the track to be put in shape and kept in shape for higher speeds.
2. Massive improvements in grade crossing protection including changing the timing of crossing signals.
3. Line relocations in many cases to reduce curvature and other impediments to speed (even the CN line through the Mississippi Delta has some speed restrictions on curves!)
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Amtrak George
Lead Service Attendant
My message fired too soon! I was going to add that I doubt the freight lines would want to raise passenger speeds in most cases, due to liability and safety concerns, as well as problems getting a faster passenger train around the freights.
Another related thought: On the City of New Orleans, the line I ride the most, it would be a very uncomfortable ride (and possibly dangerous) to increase the speed over what it is now, without a good bit of track work.
Another related thought: On the City of New Orleans, the line I ride the most, it would be a very uncomfortable ride (and possibly dangerous) to increase the speed over what it is now, without a good bit of track work.
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Nathanael
Guest
As I say, if the freight railroads know which side their bread is buttered on, they'll use 90 mph running where they already maintain the track to the right standards, if it assists to keep Amtrak "in slot", and probably not otherwise. (I am not sure all of them know which side their bread is buttered on.)
Swadian Hardcore
Engineer
The Shinkansen isn't that comfortable though, Green is 4-abreast and Standard is 5-abreast. They use standard gauge, not any form of broad gauge.
I've taken Deutsche Bahn many, many times, I still think the IC is more comfortable than the ICE as far as seats go. The ICE might ride a bit smoother, but they're all smooth to me.
I'm sure a MU could be made as comfortable as a separate railcar, but it just seems harder, and it's even worse when you try to install Sleepers. China seems to be the only one doing OK with Sleeper HSTs.
For the state supported corridor trains, the state would or could pay for track upgrades for higher speeds. The state may be able to get matching or significant federal grant funding from the TIGER program, HSIPR if it is funded again, or other federal programs. The state may pay for grade crossing upgrades as part of road safety and congestion mitigation initiatives. Number 3, line relocations, can be expensive, which means that it prety much happens only as part of a corridor project or if the freight railroad is doing for their own purposes.
The more miles of the LD routes that are shared with corridor and commuter services, the better off the LD trains are. The full implementation of PTC may provide some speed increases, but the completion of all the current HSIPR and TIGER grant funded projects and various state funded & freight railroad projects will probably help more by 2017. The implementation of PTC is clearly going to be delayed or stretched out in incremental fashion beyond 2015, well that is, if Congress does not go into total gridlock.
Much of the current Class IV track in the east is brought up to Class V standards when there is a major renovation project. The problem is, railroads choose not to maintain Class V as the inevitable wear and tear happens. Instead they allow the track gradually to fall to Class IV in places and then hold the line at Class IV with ad-hoc maintenance before the next major renovation.
From the perspective of freight railroads in the east, there is little incentive to maintain track consistently at Class V. Most of them are content to run freight at 50 or 60 mph max (intermodals perhaps a little faster) in order to conserve costly diesel fuel. They would not run freights faster than 70 even if the track and signals allowed it. The distances in the east are just not long enough for incremental speed to make a difference to freight shippers, especially when you factor in the terminal delays.
So, if CSX or NS or CNIC track is to be maintained consistently at Class V, somebody has to pay the incremental cost... Amtrak, the state DOT, whoever. Otherwise 79 (or 70 on some railroads) will continue to be the top end for Amtrak trains on those railroads regardless of what happens with PTC.
From the perspective of freight railroads in the east, there is little incentive to maintain track consistently at Class V. Most of them are content to run freight at 50 or 60 mph max (intermodals perhaps a little faster) in order to conserve costly diesel fuel. They would not run freights faster than 70 even if the track and signals allowed it. The distances in the east are just not long enough for incremental speed to make a difference to freight shippers, especially when you factor in the terminal delays.
So, if CSX or NS or CNIC track is to be maintained consistently at Class V, somebody has to pay the incremental cost... Amtrak, the state DOT, whoever. Otherwise 79 (or 70 on some railroads) will continue to be the top end for Amtrak trains on those railroads regardless of what happens with PTC.
Ryan
Court Jester
What is it about MUs that makes you think that installing a comfortable interior (sleeper or coach) is inherently more difficult?
jis
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The logic of that statement, or lack thereof IMHO simply beats me. What has MU or not got to do with internal furnishing? Afterall the car shell and interior space is the same whether it is part of an MU consist or not.
Swadian Hardcore
Engineer
Well, as I said, some people are doing good with overngiht MUs that have sleepers. I'm talking about the old City of Portland, which ran with a M-10000 DMU and they had to reduce the size of sleeping berths compared to regular heavyweight railcars of the time. See this: http://www.streamlinerschedules.com/concourse/track7/cityportland193605.html
I read a while ago that the old Santa Fe Chief of the 1950's and 1960's ran a good portion of its route at 100 MPH. If Amtrak is limited to 72 MPH max. on its LD routes, this only goes to show how backwards passenger train travel has become. Amtrak trains are all capable of running more than 100MPH, then why do we have 70 or 72 as the maximum speed?
Swadian Hardcore
Engineer
It's actually 79 most of the time, not 70 or 72. But I do see what you mean. The trains have gotten slower compared to previously. The SWC still runs a good portion at 90 mph though. Most Amtrak locomtives are capable of 110 mph. Back then I hear the elite trains would break speed limits if they were late to get back on time. Not on Cajon Pass, that was too dangerous to go fast.
Let me try again because the message doesn't seem to be getting through. Amtrak trains outside the NEC are slower, on average, than their 1950s predecessors because today's freight railroads have no incentive to support high speeds. Instead, in order to reduce costs while maintaining speeds that are perfectly adequate for freight, many railroads eliminated 90 mph running and all of them eliminated anything faster.
The speed of an Amtrak train is limited by the lowest of the following:
Yes, in the 1950s it was common for an engineer to exceed the speed limit when making up time. That was then and this is now. It never happens these days. Never.
The speed of an Amtrak train is limited by the lowest of the following:
- Track condition. FRA Class III = 60 mph. Class IV = 80 mph. Class V = 90 mph.
- The usual speed restrictions on curves, through cities, across interlockings, up and down steep grades, etc.
- The railroad's own limit. Some freight railroads limit passenger trains to 70 regardless of other factors.
- Signals. None = 59 mph. ABS/CTC = 79.
- Locomotives. Nearly all Amtrak locomotives are geared for 100+, however.
- Cars. Not a factor outside the NEC; Amtrak won't carry a private car whose running gear slows down a train.
Yes, in the 1950s it was common for an engineer to exceed the speed limit when making up time. That was then and this is now. It never happens these days. Never.
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