• Acela Speeds

  • Discussion related to Amtrak also known as the National Railroad Passenger Corp.
Discussion related to Amtrak also known as the National Railroad Passenger Corp.

Moderators: GirlOnTheTrain, mtuandrew, Tadman

  by ApproachMedium
 
The poles being closer together has little to do with speed, it has to do with the constant tension catenary sections. There are already some improvements from the upgrades, but not from the wire/catenary sections. As of right now we have only seen the benefits of the new progressive high speed signal system that was installed along the way. The system has greatly improved the following of trains on the same track since the system can give you i think 5 different cab aspects vs the previous 3. You now can get clear, cab 80, approach medium, approach and restricting where before it was clear, approach (30mph) and restricting. So youd get up to 110 or 125 and then get too close to a train and bam, cab drops to approach. Put the brake on, do 30 for a mile, it comes up, speed up, drops again. Now you can usually follow an NJT train at 80 or 45 depending and not drop to such low speeds. It really keeps the trains moving.
  by gokeefe
 
Wow that was awful. I never would have imagined that the system would have been setup so tightly.
  by ExCon90
 
Regarding the posts above about the nonstop Metroliner, true--that Metroliner was leaving NCR with empty seats. On a historical note, Baltimore enacted an ordinance around the time the Union and B&P Tunnels were built requiring all trains operating through Baltimore to make a station stop in that city, and the City Council blew the dust off the ordinance and started to make difficulties over that nonstop Metroliner, but the situation resolved itself when Amtrak discontinued the nonstop to fill seats. I suppose the issue could be raised again if nonstop Acelas were introduced, but I don't see a city ordinance overriding interstate-commerce implications. They'd have to try to make a safety issue out of it.
  by bostontrainguy
 
What about the section in Massachusetts or Rhode Island where they also tested for 160 mph? That is modern constant-tension catenary. Are those stretches capable of handling the higher speeds without additional modification? Why hasn't it been done?
  by ApproachMedium
 
Design speed for the acela is 160mph. They have always accounted for 10mph grace over top speed, in case of speedometer inaccuracies etc. With modern electronics that is not as necessary. Anyhow the track is maintained to achieve that speed as well as the wire but the signal systems top speed is programmed at 150. They could change it, but im not sure they are going to until the new train sets come out which will have a higher top speed.
  by bostontrainguy
 
So these stretches in New England could have been used as a test bed for 160 mph without any modification. Wouldn't that have been the better choice?
  by east point
 
Wonder if NE stretches not long enough for the sustained speed tests ? Another item might have been testing the variable tension CAT ( PRR ) at those speeds to verify how that CAT behaved at those speeds ? If it had passed then constant tension might not have been required for 160 ? Wasn't the fastest recorded speed 171 MPH ?

Then again there may ( probably ) have been other measurements. Wheel rail interaction, car action under that class of track ( PRR ) which has an older base and subgrade, PAN bounce, Operation under 25 hZ 12 kV compared to previous tests under 25 kV 60 hZ ? etc.
  by Matt Johnson
 
During early Acela testing the train reached an official max of 168.8 mph near Kingston, Rhode Island. During more recent testing through the Princeton Junction, New Jersey area, the Acela is unofficially reported to have exceeded 170 mph, likely breaking the UA Turbo record but alas, not officially recorded as doing such.

The Avelia Liberty will be 186 mph capable in the tilt version (with the potential for a 220 mph variant). I wouldn't be surprised to see it smash the existing records during testing through Princeton Junction!
  by Nasadowsk
 
Matt Johnson wrote: I wouldn't be surprised to see it smash the existing records during testing through Princeton Junction!
I would - most HSTs have pretty awful acceleration rates, being geared for such high speeds. The run through there isn't very long and you might not be able to get to full speed before you hit the next speed restriction...
  by ApproachMedium
 
bostontrainguy wrote:So these stretches in New England could have been used as a test bed for 160 mph without any modification. Wouldn't that have been the better choice?
No because the sections up there are double track. The seconds down in NJ are 4 track and Amtrak dispatches the lines. So we have good control where they could close the two middle tracks and run testing while keeping the two outside tracks open for regular traffic during the over night. It is essential that no other trains pass the high speed test run on the other high speed track because of the wire movement in the crap tensioned PRR cat wire. With the excessive bounce you could cause pantograph damage at those speeds.
  by johndmuller
 
ApproachMedium wrote:
The system has greatly improved the following of trains on the same track since the system can give you i think 5 different cab aspects vs the previous 3. You now can get clear, cab 80, approach medium, approach and restricting where before it was clear, approach (30mph) and restricting. So youd get up to 110 or 125 and then get too close to a train and bam, cab drops to approach. Put the brake on, do 30 for a mile, it comes up, speed up, drops again. Now you can usually follow an NJT train at 80 or 45 depending and not drop to such low speeds. It really keeps the trains moving.
Wouldn't the same sort of thing be happening in this scenario anyway, just not with as extreme speed changes? The NJT train is still going to be there and will be setting the effective max speed; I suppose if one knew the situation, one could just go 79 or whatever NJT is doing and not have to ping pong up and down much if at all so long as there was enough separation.
  by ApproachMedium
 
It doesnt work that way, eventually you get closer and you go from clear to approach. The blocks used to be very long. They are much shorter now and with the progressive block system it understands train speeds and will negotiate the cab signal indications for the train following the train ahead of it accordingly. Trust me, as an experienced engineer with both systems the new system works much better at keeping the traffic flowing even if its not at track speed. The NJT trains currently are good for 100mph and 80 for MU. They will be increasing the NJT multilevel trains to 125mph as part of the upgrades eventually. The same cars on MARC are now good for 125 and run on Amtrak B class speed tables vs C class speed tables of the previous.
  by R36 Combine Coach
 
Matt Johnson wrote:The Avelia Liberty will be 186 mph capable. I wouldn't be surprised to see it smash the existing records during testing through Princeton Junction!
Westinghouse Metroliners 800 & 802 hit 175 mph on this very stretch on 12/17/67, so it is within reach.
  by gokeefe
 
Having traveled on Acela through Kingston a few times at 150 MPH it seems so unbelievably fast to think of 175 MPH.

Hopefully Avelia Liberty will be able to operate at or very close to full capability.
  by AC4619
 
Couple quick thoughts. First, it's not surprising, but nevertheless a bit disheartening, that a project that was once supposed to bring CT cat to the entire speedway, is now a mix of upgraded VT and CT. It's 2017 (albeit, the year is a terrible argument to make for almost anything)....amtrak should not be installing NEW VT cat. In the current administration it's presumed that they're not going to get additional funding for overruns, but, it's frustrating that they've overrun in the first place. This isn't exactly cheap by international standards per mile, and we aren't even going to get a full stretch of 1990s-modernism to show for it.

Second, recently took the Acela. On a weekday. During rush hour. On a non-holiday. It was EMPTY. I mean, there were 10 people in the entire car I was in. Even at the prices they're charging, not sure how their overall ridership is right now, they couldn't have been making a profit on the train I was on. Not that surprising--on some stretches, the Acela takes LONGER than the REGIONAL, at a similar time. Which is ostenisbly insane. In particular, until the most recent timetable, Acela 2100 was slower PHL-NYP, than Regional 180/comporable. It's still similar now: 727-844 (Regional) vs 736-852 (Acela). So, you save...one minute, on the Acela, for the low low price of...3x a regional saver fare. Sorted by duration, several other Acela's are comporable to, or slower than, regionals and keystones. Obviously, this includes schedule padding, but it's unacceptable for a premium "high speed" product, to be slower, than your non-high speed product. Granted, WAS-NYP, the Acela saves you time, 30 minutes worth (and to that end, interestingly enough, 2100 happens to be amongst the fastest runs), but I'm wondering if companies are trending more towards the notion that it isn't worth the price differential (excepting executives).

Third, some of the saver-Acela fares that once existed for the evening NYC and WAS departures have now disappeared. It's interesting because it indicates either these runs are performing well enough that no incentives need to be offered to adequately fill the train to profitability, or, a change in direction and style due to new CEO Richard Anderson. For those who follow aviation, Anderson was famous for working to make delta into a bit of a "premium product for a premium price" model. E.g., He took the position and led the company towards a model in which service quality--timeliness, aircraft, crew professionalism etc, commanded a bit of a premium over the competition. Similarly, he worked to devalue a bit the FF program, and reduced discounts for premium cabins and products. And, given Delta's success, the strategy was effective. I'm curious to see if the slow disappearance of saver fares on the Acela lately is reflecting that.

On a related note, Amtrak's marketing hasn't kept pace with these changes--their website still advertises saver acela fares on late night and Saturday trains. However, a recent search through many different route pairings and dates, turned up almost no saver acela fares (there were a few, but not many). Similarly, I got an email yesterday advertising "20% off NE regional tickets with saver fares"--the current saver rates are 25% off. A check of fares last night still had a 25% discount, so I'm musing over whether the reverse occurred (marketing ahead of actual fare changes). Given that Amtrak on the whole though is considered a premium travel product in the NE, it'll be interesting to see how all of these factors (fares, ridership, speeds/schedule times), change, under anderson.

I do also find it interesting that Amtrak hasn't increased speeds to 160 mph on the sections of track in RI/MA, that can support it. At the very least, marketing opportunity & good test bed. As far as acceleration goes, Acela is very overpowered, purposefully, because of all the curves and speed changes. While it may not be able to HOLD 160 for a long time, one presumed it could be reached in existing 150 mph sections.
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