posted
I don't know how many others feel as I do, but...when I see the Acela Express passing through midtown Elizabeth, NJ, around the reverse curve located there, and the train does not show any sign of moving faster around these curves than their non-tilting counterparts, it makes me roll my eyes in utter disgust. What was the point of the active-tilt suspension system, then, if the train is not going to go faster around a curve than a non-tilt train?? (In fact, what I observed in particular today was an Acela Express going around the curve, southbound, in its usual lackadaisical fashion...followed by a NJ Transit train consisting of an ALP-44 "toaster", equivalent to an AEM-7 but with a slower top end, plus six unrebuilt Comet II cars, which are much like Amtrak's Horizon cars, which appeared to be rounding the curve at a faster rate of speed than the modern tilting wonder that preceded it five minutes beforehand!)
When first advertised, this active-tilt system was supposed to be so marvelous that it would allow trains to take curves at between 100 and 125 mph, while keeping passenger comfort at a maximum. (I believe that trains can stay on the rails while rounding curves of certain radii at these speeds, but the passengers would be thrown to one side of the train when the centripetal forces kicked in, not to mention being made extremely ill by the G-forces.)
Oh, I could go on and on...but since the former PRR is supposed to be one road where the loading gauge is not violated, i.e. on the sides of the cars, I'd like to know why I don't see the new trains tilting and/or going faster around curves than their decades-old non-tilting colleagues. Anyone want to take a stab at this...?
irishchieftain Member # 1473
posted
If anyone does decide to reply, try to use this thread, since I seem to have accidentally generated a duplicate. I'm going to have to try to contact the "forum leader(s)" to delete the duplicate...
vthokie Member # 1456
posted
I don't know what the story is with the curve at Elizabeth, but there certainly are numerous curves where the Acela Express is authorized for higher speeds. One example is a few miles south of you, where the Acela Express is authorized for 95 mph on the curve in Metuchen, and all other trains are held to 80 mph.
Gilbert B Norman Member # 1541
posted
To reiterate a discussion on railroad.net at which both Mr. Helfner and I participated, it probably was time for Amtrak to offer "premium" equipment for their "premium class" of Corridor service. 60 seat Amfleets (vs 84) simply was not enough of a product differential to justify even the "spread" between "NEDirect/Regional" and "Metroliner".
However that objective, along with the apparent public acceptance of the even higher Acela Express fare structure, could have been accomplished with conventional cars incorporating Acela Express' "smart" interior design features (i.e. they were not designed to emulate a 737's interior as were Amfleets)and hauled with existing locomotives. Maximum speed would have been 135; Boston-NY would been scheduled at 3'55" NY-Was 2'45".
The existing Acela Express equipment should simply have waited until there was infrastructure in place to support "speeds of" instead of "speeds up to" 150.
Talk about how to have saved us taxpayers a few $$$$$$!!!
[This message has been edited by Gilbert B Norman (edited 05-04-2002).]
vthokie Member # 1456
posted
I disagree. If Amtrak was going to purchase new equipment for the Northeast Corridor (which they needed to do), might as well get something fast and modern. It's about time the U.S. got a real high speed train! Yeah, it's too bad that there's not more 150 mph running, but there will be eventually, so it makes sense to look to the future when creating specs for a new train. I mean, trains last a long time! It would be foolish to base the train's capability on current infrastructure limitations.
Now, if you want to criticize a purchase, how about Amtrak buying Talgos for 79 mph operation in the Pacific Northwest, with no speed increases planned for well over a decade!
reggierail Member # 26
posted
Last time I rode the Talgos from Seattle to Vancouver was about 3 years ago. The snazzy Talgo cars hauled by a beat up F-40 sure looked silly. Reggie
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irishchieftain Member # 1473
posted It would be foolish to base the train's capability on current infrastructure limitations
Well, what's more foolish is putting a train with high capabilities on an infrastructure that can't support them. What you end up with is a train that looks good but does everything the other trains do (this refers to the Cascades Talgos as much as the Acela Express, of course).
Getting back to Acela Express, though: You'll never see them going faster than 90 mph on the CDOT/MTA-controlled part of the Northeast Corridor. In addition, the CDOT has banned the use of active-tilt on their part of the NEC because the Acela Express cars were built with two inches of excess clearance on each side (which makes CDOT fearful that a tilting train will sideswipe a train on an adjacent track)—Amtrak knew this when going in to get these trainsets built. Best chance to see high-speed running outside the current areas, i.e. in the future, should be (I don't say "will be" because I've lost faith) the former PRR NY-Washington. (And, of course, these trainsets will never reach 170 mph, which they're reputedly capable of achieving, thanks to the FRA.)
irishchieftain Member # 1473
posted
Well...anyone have an answer to that Elizabeth Reverse Curve thingy? Remember, it goes around that curve at the same speed (or slower, sometimes) than non-tilting trains. I got a very unsatisfactory answer from an Amtrak person last year at the festival in Hoboken, NJ ("Oh, there must be a speed restriction on that curve")...
vthokie Member # 1456
posted
Okay, I don't have a definite answer, but I'll take a stab at it. (Just speculation of course.) That curve at Elizabeth is posted for 55 mph, I believe. IIRC, the Acela's tilt mechanism doesn't become fully active until 60 mph. Maybe the speed around that curve would be too close to the minimum speed for the tilt mechanism.
vthokie Member # 1456
posted
quote:Originally posted by irishchieftain: Getting back to Acela Express, though: You'll never see them going faster than 90 mph on the CDOT/MTA-controlled part of the Northeast Corridor.
Well, I've heard maybe 110 mph in the future, but we'll see. Even 90 isn't so bad...the important thing is managing the traffic flow so that the trains can get from New Rochelle to New Haven on time, regardless of what speed they travel at!
quote:In addition, the CDOT has banned the use of active-tilt on their part of the NEC because the Acela Express cars were built with two inches of excess clearance on each side (which makes CDOT fearful that a tilting train will sideswipe a train on an adjacent track)—Amtrak knew this when going in to get these trainsets built.
I've been wondering, are Metro North's tracks actually closer together than on the rest of the NEC?
quote: Best chance to see high-speed running outside the current areas, i.e. in the future, should be (I don't say "will be" because I've lost faith) the former PRR NY-Washington. (And, of course, these trainsets will never reach 170 mph, which they're reputedly capable of achieving, thanks to the FRA.)
Best place for 150 mph, IMO, is from New Brunswick through Princeton Junction to Trenton, NJ. There are, I believe, two minor 130 mph curves between New Brunswick and Trenton, but other than that it's dead straight track. That's where I think the Acela Express should definitely be allowed 150 mph, and Amtrak needs to make replacing that old variable tension catenary a priority!
As far as the train being capable of 170 mph, of course it can go faster than it does in revenue service! It's officially rated for 165 mph (10% above its max revenue speed), and I think you'll find that most trains have some margin specified. (The TGV's, for example, are capable of more than 186 mph.) I'll settle for more 150 mph running!
[This message has been edited by vthokie (edited 05-05-2002).]
dguruswamy Member # 1330
posted
The reality is that while replacing the catenary is a goal, the priority is replacing all the substations that feed the catenary. While the catenary is old and ugly it's still functional, and replacing it is not likely to be a priority for a company over $3B in debt.
quote:Originally posted by vthokie: Best place for 150 mph, IMO, is from New Brunswick through Princeton Junction to Trenton, NJ. There are, I believe, two minor 130 mph curves between New Brunswick and Trenton, but other than that it's dead straight track. That's where I think the Acela Express should definitely be allowed 150 mph, and Amtrak needs to make replacing that old variable tension catenary a priority!
[This message has been edited by vthokie (edited 05-05-2002).]
rresor Member # 128
posted
Okay, I've posted about this subject before, but maybe not on Trainweb.
1) The tilting mechanism is purely for passenger comfort. It has nothing whatever to do with how fast the train can run (the power cars don't tilt).
2) Amtrak asked the FRA for permission to run with nine inches of "cant deficiency" (nine inches over balancing speed, which is the speed where outward tilt exactly equals the superelevation of the high rail). Due to continuing unsolved problems with the tracking of the trucks (they "hunt" unpredictably on curves), FRA limited the train to (IIRC) 7 inches north of NYP and 6 inches south. This holds down maximum curve speeds, and FRA people tell me the hunting problem is unlikely to ever be corrected.
3) For the same reason, FRA limits the maximum speed of the train in *any* curve to 130 mph.
4) Even if the train were to perform to specifications, 150 mph would be permitted on only 45 miles of track between NYP and WAS.
5) My April 2001 timetable gives a speed of 65 for Acela Express through the Elizabeth reverse curve, vs. 55 for Amfleet. So there's a little difference.
vthokie Member # 1456
posted
quote:Originally posted by rresor: 1) The tilting mechanism is purely for passenger comfort. It has nothing whatever to do with how fast the train can run (the power cars don't tilt).
Yes, I'm aware of that. Which leads me to another question...if the X2000's flexible axle mounts on the trucks were the key to actually taking curves at higher speeds, how was the Acela supposed to have the same capability with conventional trucks?
quote: 5) My April 2001 timetable gives a speed of 65 for Acela Express through the Elizabeth reverse curve, vs. 55 for Amfleet. So there's a little difference.
Well, guess that answers the question!
irishchieftain Member # 1473
posted a company over $3B in debt.
I've always wondered who Amtrak's creditors are...
irishchieftain Member # 1473
posted My April 2001 timetable gives a speed of 65 for Acela Express through the Elizabeth reverse curve
Looks like your timetable lied...and assuming that the AE ever does that speed around the curve, how is that a significant improvement over the conventional trains? Like I said, the AE does not do 65 through Elizabeth Reverse Curve, bottom line. Conventional trucks still have high capability to keep the train on the track through curves, still and all...but since this is still a big issue, why did Amtrak use a technology supposedly from yesteryear on a "train of the future"???
The TGV's, for example, are capable of more than 186 mph
Much more...they do 190 mph in regular service nowadays, and the test train that ran at 327 mph is well documented...
Even if the train were to perform to specifications, 150 mph would be permitted on only 45 miles of track between NYP and WAS
Which 45 miles? And what are they scared of? The whole Acela Express project sounds lamer and lamer with each retelling. It's a lot more than 45 miles between NY and Washington...besides, how much trackage can the AEM-7s with Amfleets get up to 125 mph on??? That ought to tell you just where the Acela Express can do its vaunted 150 mph.
Due to continuing unsolved problems with the tracking of the trucks (they "hunt" unpredictably on curves)
Hmm?? And I thought that this problem was fixed and all, what with the various reports on Railroad.net to the affirmative. So the Acela Express is just the new E-60, then, but just not as bad...? It's a sad state of affairs when a B-B locomotive hunts; really lackadaisical design, I would say. (Although, come to think of it, it looked to me like an HHP-8 I was observing passing through Linden, NJ today pulling 10 Amfleet I cars was indeed hunting just a little.) Can Amtrak do anything right???
The tilting mechanism is purely for passenger comfort
Ad nauseam; this is about the umpteenth time I've heard that. However, on the same note, the passenger comfort was supposed to be maintained at higher speeds through curves than conventional equipment. Active-tilt becomes quite redundant when you run the train at the same speed through the curve as conventional railcars. Correct?
the priority is replacing all the substations that feed the catenary
Now this is something new. Is the root of this the goal of converting the NEC from 12kV 25Hz to 25kV 60Hz, which was supposed to have started two decades ago?
Gilbert B Norman Member # 1541
posted
I believe that comment regarding Messrs. "SwamifromArlingtonCounty" and Helfner's noting of Amtrak's $3B of debt should be deferred until their Annual Report for FYE Sep 30-01 is released.
I would like to think that auditors KPMG will be insistent in the inclusion of all liabilities, including capitalized leaase obligations.
Remember; read the Footnotes!!!
GBN, CPA
rresor Member # 128
posted
Timetable #7, April 29,2001, page 163:
"First curve west of MP 14 (that would be the Elizabeth reverse curve):
Track 1 55 Track 2 65 Track 3 65 Track 4 55
"Curve east of Elmora": 55 all four tracks
BUT, speed on tracks 2 & 3 in first curve is same for Acela Express and other trains.
The 45 miles in question are between New Brunswick & Trenton and between Perryville and "Gunpow" interlocking.
It's 225 miles from NYP to WAS.
I agree with you; Acela Express was a fraud from the beginning.
"Tomorrow's train today on yesterday's tracks".
irishchieftain Member # 1473
posted The 45 miles in question are between New Brunswick & Trenton and between Perryville and "Gunpow" interlocking...(it's) 225 miles from NYP to WAS
OK...well, that puts it in black-and-white. Well, to re-iterate one of my other queries, on how much of the 225 miles is 125-mph running permitted for AEM-7/Amfleet trains (or the second coming of the "Metroliner", if you like)? Are there any milepost markers where the Acela Express is permitted either 140 or 145 mph beyond the delineated 150-mph territory? Well...all of this is spitting in the wind, in light of the defrauding of the US that the Acela Express project turned out to be.
How prone to hunting are AEM-7 wheel trucks? They seem the most rock-solid locomotive on the NEC right now. It seems to me that aero-shrouded AEM-7s, regeared to 150+ mph, with Amfleet I cars retrofitted with tilt suspensions, would outperform the newer Bombardier consists. (Indeed, the original Metroliner MUs were supposed to be able to match the AE's speeds...)
rresor Member # 128
posted
AEM7s are designed for a max of 125. They work fine at that speed. The Acela Express does not ride on "TGV" trucks. The power car trucks were originally designed by Alstom for a 125-mph locomotive. The redesign for 150 mph didn't work very well, apparently -- that's why they hunt.
Where Acela Express can achieve 150 mph depends on three things:
1) ACSES (Advanced Civil Speed Enforcement System) installed and working 2) Constant-tension catenary (without that, max is 135 for both Acela Express and Metroliner consists) 3) Track geometry (AE is restricted to 130 mph at present on ANY curve by the FRA).
Nevertheless, Amtrak's "Year 2010 Plan" shows no more than 45 miles of 150 mph operation (with some curve restrictions) even when the three conditions above are achieved.
If (ever) FRA allows operation at increased "cant deficiency" and lifts the 130 mph restriction on curves, some of the curve restrictions will be lifted.
posted 