In a way, both POV's have merit. Let us assume that point NYP to point DC is 200 miles. In a 4 hour period, we can have trains depart one way every 30 minutes. If they average 50 mph, we can only get one train from point to point. If 100 mph, twice as many. That ratio lowers obviously over a 10-15 hour day, but the equipment utilization advantage of higher speeds also kicks in.
C&NW, CA&E, MILW, CGW and IC fan
A moving-block signal system can increase capacity over a fixed signal system. Moving block systems without wayside signal and only cab signals and automatic preempting safety train control could do the job and are possible within today's technology.
schlimm In a way, both POV's have merit. Let us assume that point NYP to point DC is 200 miles. In a 4 hour period, we can have trains depart one way every 30 minutes. If they average 50 mph, we can only get one train from point to point. If 100 mph, twice as many. That ratio lowers obviously over a 10-15 hour day, but the equipment utilization advantage of higher speeds also kicks in.
If you depart one train every 30 minutes, the flow past any point in the system is the same regardless of speed.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
daveklepper A moving-block signal system can increase capacity over a fixed signal system. Moving block systems without wayside signal and only cab signals and automatic preempting safety train control could do the job and are possible within today's technology.
A moving block signal system will maximize your capacity, regardless of train speed. Flow rate will be virtually the same for any speed.
One side of this argument is measuring headways in minutes and in that frame of reference it is valid.
If you measure headways in signal blocks or miles you will get a different result. The faster a train clears a block, the sooner the block is available for the next train.
Dave
Lackawanna Route of the Phoebe Snow
Yes Phoebe-Vet, but the faster the allowable train speed, the longer the block, so the two cancel. The only way to increase capacity is by going to moving blocks, and this comes close to doubling capacity. In other words the distance between signal spacing for the speed becomes, with a moving block system, the safety block behind the moving train. Whereas, with fixed blocks, the train behind sees a red signal, until the train ahead is actually two blocks ahead.
Moveable blocks and cab signals are the keys to speed and capacity...but still commuter roads find getting another train in an hour by speeding things up works.
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Of course better and more reliable braking can allow higher speeds while retaining an existing block system. Possibly commuter railroads with captive consists not interchanged should consider magnetic track brakes which allow modern light rail cars to mix with traffic and operate in pedestrian zones with excellent safety. They would be used only in emergency brake applications. West Penn used them on interurban cars built in 1912. Standard on all PCC streetcars, but I do not believe they were retained on the Spam Cans (CTA 6000's). They were used on the C&LE "Red Devils" and the Indiana "High Speeds."
schlimm Amtrak needs separate, dedicated tracks, not shared with commuter trains (or freight, for that matter) in the NEC. I suppose the bottleneck is the Hudson tunnel. How many tracks is it? Is that why there was a proposed new tunnel that was rejected by Christie?
Amtrak needs separate, dedicated tracks, not shared with commuter trains (or freight, for that matter) in the NEC. I suppose the bottleneck is the Hudson tunnel. How many tracks is it? Is that why there was a proposed new tunnel that was rejected by Christie?
The Hudson tunnels (aka North River Tunnels) consist of 2 tubes with one track each. So you have a double track line connecting New York Penn to anything south.
Additional tracks are sorely needed for more capacity. Which was what ARC that Christie killed was supposed to bring in its way. And what Amtrak is exploring adding with its Gateway Program.
But track and platform capacity in Penn Station itself is also an issue. And Metro North wants Penn Station access!
Phoebe VetIf you measure headways in signal blocks or miles you will get a different result. The faster a train clears a block, the sooner the block is available for the next train.
Nope. Because faster trains need longer blocks - or more blocks - to keep safe separation.
henry6but still commuter roads find getting another train in an hour by speeding things up works.
Wow, you just won't give it up....
Just saying it doesn't make it true. Which one? Where? When? What was MAS before and after?
CJtrainguyAdditional tracks are sorely needed for more capacity. Which was what ARC that Christie killed was supposed to bring in its way. And what Amtrak is exploring adding with its Gateway Program.
ARC was a bad idea. Gateway is much better. Christie probably did the right thing killing ARC.
To get more capacity, you have to fix the bottlenecks, which are usually terminal areas in the freight train world, but are often line capacity in the transit/passenger world. Once you get to a movable block system and the best possible train braking system, the only thing left is adding tracks.
daveklepperOf course better and more reliable braking can allow higher speeds while retaining an existing block system. Possibly commuter railroads with captive consists not interchanged should consider magnetic track brakes which allow modern light rail cars to mix with traffic and operate in pedestrian zones with excellent safety. They would be used only in emergency brake applications. West Penn used them on interurban cars built in 1912. Standard on all PCC streetcars, but I do not believe they were retained on the Spam Cans (CTA 6000's). They were used on the C&LE "Red Devils" and the Indiana "High Speeds."
Track brakes for safety would be helpful for line capacity, but they'd have to be "failsafe" if you wanted them as part of your PTC system.
CJtrainguy schlimm Amtrak needs separate, dedicated tracks, not shared with commuter trains (or freight, for that matter) in the NEC. I suppose the bottleneck is the Hudson tunnel. How many tracks is it? Is that why there was a proposed new tunnel that was rejected by Christie? The Hudson tunnels (aka North River Tunnels) consist of 2 tubes with one track each. So you have a double track line connecting New York Penn to anything south. Additional tracks are sorely needed for more capacity. Which was what ARC that Christie killed was supposed to bring in its way. And what Amtrak is exploring adding with its Gateway Program.
Actually ARC would have been NJT trains only, no Amtrak, and would have terminated at a stub station which would have required deadhead moves and quick turnarounds in order to keep station tracks clear. In hind sight Christie probably made a good move...there were many at the time who thought the same. It did not utilize NYP, did not integrate or interface with Amtrak, LIRR, or other NJT services....it was a quick and rash concept pushed through more by exasperation than sound judgement...but it did get adrenaline flowing and ideas being considered and adapted.; however, it is mostly still talk.
I never did like the separate station next to New York Penn for ARC, because inherently the flexibility of bringing trains in on any track is a good thing. So in that respect, the Gateway Project is an improvement.
The negative in killing ARC is that everything was kicked back to the planning and talking about stage, rather than building something.
At least there is some very preliminary protective building activity for the Gateway Project taking place on Manhattan now.
Obviously additional tunnels will be built eventually. I'd like to see that be sooner rather than later though.
And at some point we're going to have to deal with the fact that the current North River tunnels are now over 100 years old…
Right on all matters....but if Christie didn't put the brakes on ARC, millions would have been spent in waste. I'd like to see a downtown set of tunnels....from the old Erie alignment perhaps, under the Hudson and Manhattan to Brooklyn or Queens perhaps tying into the LIRR or other existing tracks for yarding or through services to LIRR or even New England or loop back to NYP....lots of need for lots of upcoming transit, commuter, and regional needs.
I thought I was keeping up with what is going on in the NYC-NJ area, but I must confess that I do not recall anything about a Gateway project. Can one of you fill me in on this?
Thanks,
Johnny
Gateway is use of present NYP and adding tracks from another tunnel project basically. Includes Amtrak and NJT. And LIRR to a lesser extent. Gets money from Amtrak and not all on the shoulders of NJ or NJT. Also calls for revamping all of NYP structure wise.
Thanks, Henry.
CJtrainguy I never did like the separate station next to New York Penn for ARC, because inherently the flexibility of bringing trains in on any track is a good thing. So in that respect, the Gateway Project is an improvement. The negative in killing ARC is that everything was kicked back to the planning and talking about stage, rather than building something. At least there is some very preliminary protective building activity for the Gateway Project taking place on Manhattan now. Obviously additional tunnels will be built eventually. I'd like to see that be sooner rather than later though. And at some point we're going to have to deal with the fact that the current North River tunnels are now over 100 years old…
Official outline of the Gateway Project here:
Gateway Project pdf
Thanks, CJtrainguy. I am not sure how I missed it, but, miss it I did.
schlimm The only way to increase the passenger capacity of the NEC without enormous infrastructure costs is to increase train speeds, thus allowing more trains to run per hour.with the same distance between them for safety. As time goes by and the new, faster Acela trains come online, the regional trains will likely need to be cut back because of those capacity restraints.
The only way to increase the passenger capacity of the NEC without enormous infrastructure costs is to increase train speeds, thus allowing more trains to run per hour.with the same distance between them for safety. As time goes by and the new, faster Acela trains come online, the regional trains will likely need to be cut back because of those capacity restraints.
There also needs be some infrastructure upgrades. Not the $40B+ that will speed up the NEC to the planned- 160 MPH but funds to lengthen trains to 14 cars. That will take some station's platforms to get longer. Trenton, Wilmington, Baltimore, and some Washington platforms. NYP does have only a few track platforms that can take 14 but maybe very precise scheduling can be implemented. Ultimately the above stations can be lengthened to handle 18 cars + 2 motors. NYP can only lengthen when the Gateway project is completed. That cost may be as much as $10B.
14 car regional trains will require a lot more coaches & business class cars. 14 lengths will also allow Acela-1s to be coupled together for higher capacity once Acela-2s are built to cover more slots..
Exactly how 14 cars will fit NYP -- BOS is unknown by me.
Instead of longer trains with accompanying upgrades at stations, an option is to look at bi-level train cars. The French have their bi-level TGV Duplex and bi-level train cars and MUs are in use all over Europe for local, regional and some long-distance trains.
NJT is of course already using bi-levels on some of their trains.
The NEC cannot handle bi-levels without changes in vertical clearances. And unless the new tunnels are built...
schlimm The NEC cannot handle bi-levels without changes in vertical clearances. And unless the new tunnels are built...
Somebody needs to tell NJT that...
These things run into NYP everyday! I've even ridden them in and out of there a few times. Nothing terrible happened...
So, the big question is "why aren't cars like these in Amtrak's plans?" ...at least for NYP to WAS service. It would buy some time for infrastructure changes to accommodate longer trains.
FWIW, several of these were fitted with nice reclining leather seats and lounge areas for use in the short-lived Atlantic City Express Service (ACES - clever, huh?) that ran NYP to Atlantic City (with an electric locomotive on one end and a diesel on the other.
It is entirely correct that NEC and specifically the North River Tunnels can't handle Superliners. And if I understand correctly, if Superliners get to New York Penn Station, since the platforms are high level and the Superliners have doors designed for low platforms, you can't get on/off anyway.
But bi-levels that are built to fit the loading gauge of the NEC are perfectly fine, as NJT demonstrates every day.
Bi Levels are lower than Superliners. As for price being too high....enough people pay the price to the point that trains are often sold out...so as long as people buy and trains are full, the price can't be too high. It is when the trains are empty that the price is too high.
I agree. I think these bilevels modified with reclining seats would make great NE Regional Direct cars for NY-Boston service (and Portland, ME - Newport News, Norfolk, and Caronlina service for that matter once the essential Boston tunnel gets built). I also think that LIRR should buy bilevel mu cars. Perfectly practical, more comfortable than 3-2 seating in M-9's or M-7'sm and more capacity.
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