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Are cab cars, DMUs a safety problem?

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Are cab cars, DMUs a safety problem?
Posted by Paul Milenkovic on Monday, July 7, 2008 1:17 PM

In another thread I presented some ideas of how the current levels of fuel consumption of Amtrak corridor trains could be greatly improved with some equipment changes. 

Much of the discussion had centered on whether load-factor assumptions are a "fair" way of assessing train fuel efficiency and whether load-factor could be increased by pricing policies.  Now that Amtrak (looks like it may) have capital money to acquire new corridor equipment, what changes from standard practice would be practical to address fuel efficiency by reducing the fuel used per revenue seat?

A "standard" Amtrak corridor train is operated push-pull and has a 125 ton locomotive or NPCC "cabbage" care at each end.  Don Oltmann suggested that the heavy, non-revenue "cabbage" car was an expedient when the F40s were retired as locomotives -- prior to that, I understand that they used Metroliner cars with the electric motors, transformers and pantographs taken out.  Even the Pacific Cascades Talgo, back in the pre-stress crack days when they were running Talgos, had this locomotive-cabbage book ends of the consist.  In fact, the conditions of the FRA waiver for the lightweight Talgo were to have a non-revenue 125 ton mass at each end, either a locomotive or an NPCC.

I have picked out the NPCC as a fuel waster -- not only is it the mass of two revenue cars, but the mismatch in height between it and the Horizon or Amfleet roofline results in added wind drag.  When I had suggested dispensing with the NPCC to my local advocacy group, it was suggested that I wanted to take away life-saving safety measure to the train crews.  On the other hand, the Pacific Surfliner is operated with a commuter-style cab car and does not use an NPCC.

Would it be plausible to operate cab cars or DMUs on Amtrak corridor trains, or are the days of having revenue seats at the end units of passenger consists over?  Commuter services as well as the Pacific Surfliner use cab cars, but was there some initiative on the part of the FRA after the Los Angeles commuter accident to do away with cab cars in commuter service? 

If a locomotive or NPCC at each end of a consist is a requirement, is it a requirement that it weigh 120+ tons, or are lighter weight "power cars" such as the Talgo XXI, discussed on another thread over at Locomotives, acceptable?  Would some kind of "safety cab" at the A end of a cab car or DMU be acceptable, or is the iron-clad requirement that the ends of consists be protected by non-revenue seat units that are also heavy?

Another person in our local group remembers the Alan Cripe people making a pitch to Midwest High Speed Rail Association about bringing back a Diesel-motor version of the TurboTrain, and a video was shown of the reinforced nose of the oriignal TurboTrain slicing apart a dump truck in a grade-crossing collision, emphasizing that a lighweight train could be reinforced in such a way to protect the occupants of the train.  Can this pitch be made today?

The other aspect of DMU's or "power cars" with full or partial revenue seating is the question of DMUs vs locomotive-hauled consists and maintenance practices.  The same person who criticized me for wanting to do away with NPCCs was also critical of DMUs from the standpoint of maintenance and operating costs.

If you have locomotives on one hand and railroad cars on the other hand, each can be subject to the maintenance procedures and inspections required for each class of rolling stock.  With a DMU, you have something that is both a "locomotive" and a "passenger coach" at the same time, which may present issues with both the maintenance and inspection regimes.  On the other hand, Amtrak at one time had a substantial fleet of the French, or French-derived Rohr-built TurboLiners, which had power cars with partial revenue seating space.

If for whatever reason one goes with having a locomotive at each end of the consist, are lightweight locomotives with safety cabs a possiblity?  In a discussion of tilt equipment, it was mentioned that a lighweight locomotive is required for full-speed operation on account of a Genesis or an F59 being heavy enough to spread the rails when negotiating curves at speeds the tilt cars would allow.  Or are the grade-crossing safety issues such that a full-weight locomotive is a requirement?

If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?

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Posted by CSSHEGEWISCH on Monday, July 7, 2008 2:06 PM
I'm not sure about the Talgos because of their light weight, but I think the safety issue is a phantom when it comes to conventional equipment operated as push-pulls.  Almost all suburban operations use cab cars and electric MU cars aren't that different in weight and construction from DMU's.  About the only time I see this issue raised is when there's any accident similar to the recent Metrolink collision and derailment.  I'm sure that there are a lot of commuters out there who had their ride to work delayed (locomotives are usually on the outbound end) because of a grade crossing accident involving an automobile and no derailment.
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Posted by DMUinCT on Monday, July 7, 2008 2:51 PM

   In the northeast, the "Downeaster" to Portland Maine, the "Vermonter", and the Atlantic City line is "Push Pull" operation!!  Also most commuter trains.

   All the rest of Amtrak's Northeast Corridor Trains are "locomotive hauled", 8 or more cars.  Then you have the 20 Acela Train Sets.   All Corridor trains are "Reserved" trains, tickets equal the number of seats, but no seat number, (no overbooking) and often sold out at peak hours.  The corridor already runs the HHP8 (8 thousand HP) and the AME-7 (7 thousand HP) at 110 plus mph, the Acela (12 thousand HP) up to 150mph.  The DMUs are not designed for that kind of service.  (My initials of my name have nothing to to with the Railcar with the same letters)

  All passenger trains in the U.S. must meet federal safety and crash testing standards.

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Posted by Ham549 on Monday, July 7, 2008 5:07 PM
The F40PH is very safe although same can't be said for the Genes#!+, remember this was caused by a SUV had a F40PH been leading that train the results would have probely been far less tragic.
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Posted by HarveyK400 on Tuesday, July 8, 2008 1:49 AM

The Metrolink accident may have been caused by an SUV; but it appears that the major damage was cause by the jack-knifing between cars. 

  • A heavy locomotive will not always stay on the rails after hitting an object on the tracks.
  • The mass of the trailing train needs to be absorbed in a crash; and the heavier the train, especially with a 131 ton car at the end, the more pronounced the momentum.

I think the X2000 had a safety cage around the cabs in the locomotive and end cab-coach for push-pull service.  Swedish railways are not fully grade-separated.

Similarly, I know The Netherlands and Denmark had emu and dmu trains with reinforced cabs and noses.

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Posted by oltmannd on Tuesday, July 8, 2008 10:51 AM

 CSSHEGEWISCH wrote:
I'm not sure about the Talgos because of their light weight, but I think the safety issue is a phantom when it comes to conventional equipment operated as push-pulls.  Almost all suburban operations use cab cars and electric MU cars aren't that different in weight and construction from DMU's.  About the only time I see this issue raised is when there's any accident similar to the recent Metrolink collision and derailment.  I'm sure that there are a lot of commuters out there who had their ride to work delayed (locomotives are usually on the outbound end) because of a grade crossing accident involving an automobile and no derailment.

I second this opinion.  Cab cars are more than safe enough.  There is no such thing as absolute safety - just reasonable trade-offs.

I suspect that Amtrak's "cabbages" were born more out of a need to create cab cars on the cheap than for safety considerations.  After all, they operate Keystone trains in push mode with Metroliner cab cars at 110 mph over road Xings....

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Posted by gardendance on Tuesday, July 8, 2008 12:04 PM
 Paul Milenkovic wrote:

A "standard" Amtrak corridor train is operated push-pull and has a 125 ton locomotive or NPCC "cabbage" care at each end.  Don Oltmann suggested that the heavy, non-revenue "cabbage" car was an expedient

Am I reading this right, are cab cars non-revenue? The last time I rode an Amtrak push-pull was 1992 to and from San Diego, although I've been on commuter rail push-pull since then. The cab cars carried passengers. What does NPCC mean? Is it non-passenger carrying car? That's a new acronym to me.

I often wondered how safe trains were in push mode with nothing but a regular coach at the front end. I didn't know the cab car had ballast. Is it all just ballast? I remember GO Transit in Toronto had what appeared to be locomotives at both ends, it turned out one of them was an APCU Auxilliary Power Control Unit, a former locomotive sripped of a few things so that all it could do was to provide hotel power and a cab. The locomotive at the other end was the one that gave motive power and did not have the ability, head end power, to run air conditioning and passenger lights.

Kind of like married pair MU's, one car has the pantograph and air conditioner, the other car has the brake compressor and air tanks. Any thoughts on the merits of similarly distributing functions between the 2 controlling units at each end of a push-pull consist so you get equal weight without too much dead weight? GO Transit's example seems like a lot of extra weight but the trade off may have been that they took a broken locomotive and made something useful out of it.

Like a few other posts here I really don't see much safety difference in front end protection between an old fashioned electric MU, of which the US has many examples for over 80 years at high speeds, and a locomotive pushing a cab car. I do think there must be the added danger though of that heavy locomotive at the back telescoping through all those coaches, and then crushing against a heavily ballasted cab car, or another locomotive if there was a loco at both ends of the train. Does anybody know if that rear end locomotive has better stopping power than a coach, assuming that a particular accident allowed brakes to apply? And if it does stop better than a coach is it enough to account for the locomotive's extra weight?

I don't remember the dates, but there was a Metroliner which had substitute GG1 locomotive and Amfleet which hit a big track laying machine. Comments at the time were that the accident would have had a lot more injuries if the train had the regular Metroliner MU's.

Another accident was on a New York-Philly clocker which in those years used leased NJTransit MU's. A piece of metal sticking out of a trailer train sliced several feet through one side of the lead car, I think there was at least one fatality. Chances are that accident would not have hurt anyone if a locomotive had hauled the train.

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Posted by oltmannd on Tuesday, July 8, 2008 1:31 PM

Cab cars aren't ballasted.  An NPCC is an Amtrak F40 with the engine removed and a baggage door installed in the side.  It functions as a cab-baggage car, hence the slang "cabbage".Smile [:)]

Tightlock couplers and strong buff strength requirements for passenger cars make the chances of the pushing locomotive telescoping into the cars ahead unlikely.

Certainly, a cab car provides less protection for the operator and perhaps the passengers, but the number of occurences of bad things happening is very, very small.  Perhaps the risk can be reduced more for less money by doing other things.  At some point, grade Xing eliminations are cheaper than pushing NPCCs around all over creation, for example.

It might be worth remembering that 2 AEM7s an an empty Amfleet car were not enough protection for the 17 folks who died at Chase MD year ago. 

The only perfectly safe way to travel is not to go.

 

 

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Posted by gardendance on Tuesday, July 8, 2008 6:52 PM

are you implying that fewer would have died if the AEM7s and empty Amfleet car were at the back of the train at Chase?

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Posted by oltmannd on Wednesday, July 9, 2008 6:58 AM
 gardendance wrote:

are you implying that fewer would have died if the AEM7s and empty Amfleet car were at the back of the train at Chase?

No.  Only that the arrangment and design of equipment is no panacea.

That one arragement can be determined to be "safer" than another does not mean that one arrangment is a "safety problem".

Safety on the NEC was better served at lower cost by installing LSL on the frt. trains than it would have been if the reaction would have been to beef up passenger car stength and/or train consist requirements (e.g. placing three empty passenger cars at the front and rear of the trains.)

The slight additional risk from operating cab cars at the head end of the train is more than outweighed by the operational benefits.

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Posted by passengerfan on Wednesday, July 9, 2008 7:22 AM

The Los Angeles Metro incident was a horrible event. It was a freak though. How often is someone going to attempt suicide by train and everything happen as it did. That there would be a freight train involved as well becomes a mathematical improbability.

These cars first used on GO Transit have a tremendous safety record when one considers the number of commuters transported safely each and every work day in these cars in the push -pull mode one sees just how safe these cars really are. They are not used in just Los Angeles and Toronto but Seattle, Vancouver, Stockton, New Mexico, Miami, and Salt Lake City.

I ride these cars occasionally when I need to get to the bay area and spend a day I feel perfectly safe and ride the cab car on my return.

I think the question of cab- car safety has been blown out of all proportion over the one incident. The cabbage cars are a waste and were really just a quick expedient. I still do not see the need for Acela to have power on each end. Additional cars could be pulled and passengers carried if one power unit was eliminated. There are turning facilities at Washington, New York and Boston.

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Posted by beaulieu on Wednesday, July 9, 2008 8:31 AM
 passengerfan wrote:

I think the question of cab- car safety has been blown out of all proportion over the one incident. The cabbage cars are a waste and were really just a quick expedient. I still do not see the need for Acela to have power on each end. Additional cars could be pulled and passengers carried if one power unit was eliminated. There are turning facilities at Washington, New York and Boston.

Al - in - Stockton  

Al, without a cab on both ends the Acela would need more sets to operate the schedule, also I don't think that there is enough capacity in the East River Tunnels to take the trainset to Sunnyside Yard to turn the train. Finally Acela needs both power cars to have enough horsepower to make the schedule. 

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Posted by DMUinCT on Wednesday, July 9, 2008 9:06 AM

  NPCC, AKA The Cabbage.

   A gutted F40PH with side doors to act as a Baggage car/ Control cab.  On the "Downeaster" it gives Baggage and Bike capacity to a run between Boston and Portland ME.   Northbound locomotive hauled, southbound the engineer has a full F40PH cab to work in.

   Another factor --- the F40PH fuel tank is loaded with SAND for weight!   This gives it the (aprox) braking power on the back of the train as the locomotive up front has.  

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Posted by beaulieu on Wednesday, July 9, 2008 12:06 PM
Amtrak's NPCC (Non-Powered Cab Car) were ballasted to replace the weight of the Diesel and the Alternator (which were parted out or sold) because if they weren't ballasted Amtrak would have had to  modify or replace the trucks. The brakes as designed for a locomotive would have been much too powerful for a much lighter car , which would have resulted in the wheels sliding on even a light brake application. Secondly the springs would have been much too strong resulting in the track being hammered by the wheels since the springs would provide very little cushioning. Modifying or replacing the trucks were beyond Amtrak's financial capabilities. Parts would have had to be Engineered and manufactured as there were no off-the-shelf replacements. The NPCC solved two problems, a shortage of cab cars, and a shortage of baggage cars.
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Posted by ndbprr on Wednesday, July 9, 2008 2:57 PM
Any time the crew is inchs from the font of the vehicle there are going to be more injuries than if they are not if for no other reason then that is the crumple zone.  The PRR streamlined the last of the P5a engines because of a crew being killed in a box cab.  That is the reason for the cab location on a GG1.  Now if a crew could be seriously hurt in a cab built with 1/4" or thicker plate and a cast steel underframe I think I would opt for another location if I had a choice.  Wouldn't you?
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Posted by tomikawaTT on Wednesday, July 9, 2008 4:25 PM

Looking away from North America, Japan has innumerable classes of trains (including Shinkansen) which carry passengers in the first and last cars.  A lot of them have the driver in a cab no bigger than a North American vestibule at the head end, with one sheet of steel between him and the wind.Shock [:O]

One very popular extra-fare fast (but not super-speed) train has a lounge section at the extreme front end, with the driver's cab above and behind it.  (Do people pay an extra fare on top of the train's extra fare to put themselves in harm's way?)Evil [}:)]

I have traveled thousands of kilometers aboard Japanese DMU and EMU trains, watching through the front windows (over the driver's shoulder.)  I never felt the slightest fear for my safety.  OTOH, I have traveled considerably less distance on Japanese roads, and have put innumerable buttonholes in automotive seat cushions.  Which would I prefer to do?Laugh [(-D]Laugh [(-D]

So, Metrolink has had a FEW accidents, a SMALL NUMBER of fatalities and injuries (both in absolute numbers and as a percentage of ridership,) and is so unsafe that the FRA wants to put bulletproof buffers at both ends of every train.  How many were killed and injured on Southern California freeways over the past holiday weekend?  Going by the FRA/'Advocate' way of thinking, we should all be driving around in Abrams tanks...Grumpy [|(]

Just my My 2 cents [2c].  Other opinions will differ, but the facts won't.

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Posted by beaulieu on Wednesday, July 9, 2008 5:17 PM

 ndbprr wrote:
Any time the crew is inchs from the font of the vehicle there are going to be more injuries than if they are not if for no other reason then that is the crumple zone.  The PRR streamlined the last of the P5a engines because of a crew being killed in a box cab.  That is the reason for the cab location on a GG1.  Now if a crew could be seriously hurt in a cab built with 1/4" or thicker plate and a cast steel underframe I think I would opt for another location if I had a choice.  Wouldn't you?

 

Much safer than traveling in an automobile, operating at commonly driven speeds, do you consider driving a car too dangerous? How much is the added safety worth to you if you have to pay for it personally? Convince me that you haven't traded off safety for transportation convience by driving a car.

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Posted by gardendance on Wednesday, July 9, 2008 11:36 PM
 beaulieu wrote:

 ndbprr wrote:
The PRR streamlined the last of the P5a engines because of a crew being killed in a box cab.  That is the reason for the cab location on a GG1.

Convince me that you haven't traded off safety for transportation convience by driving a car.

ndbprr: putting the GG1 cab in the center of the locomotive body certainly afforded lots of extra crew crush protection, but at a visibility cost. Like steam locomotives, camelbacks, and any long nosed loco, it was tough to see out front, especially around curves. Another part of the trade off was most of them had 2 man crews, presumably with an alert fireman looking out the left side while the hand on the brakes looked out the right side. Oops, I mean the eyes of the man with the hand on the brakes.

beaulieu: sometimes people think they're getting more safety when they leave the driving to themselves. In another thread I mentioned a friend of mine who felt unsafe trusting a public transit operator, she emphatically said that she felt safer when she was at the wheels of her car.

Related to that, a car commercial had a little baby in a car seat give a voice over: another driver cut mom or dad off, hero parent saved the day by accelerating; a truck lost its load in front of the car, again the car's magnificent performance averted the crash because the stable controls allowed them to swerve into another lane, avoiding the obstacle. Conspicuously absent from the commercial was any mention of going for the brakes to avoid the accidents. I think that this is Madison Ave playing to an unfortunate nature in many of us to think that action, pushing and aggression are better than pulling back, slowing down, or relying on the safe, courteous transportation profesionile :)

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Posted by gardendance on Wednesday, July 9, 2008 11:55 PM
 beaulieu wrote:
 passengerfan wrote:

I still do not see the need for Acela to have power on each end.

Finally Acela needs both power cars to have enough horsepower to make the schedule. 

beaulieu: I'd tend to agree with you. TGV and Shinkansen have power cars at both ends, and I expect the general consensus is that they are the epitome of high speed rail.

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Posted by DMUinCT on Thursday, July 10, 2008 3:45 PM

  The Acela design was throught to need 12,000 hp to reach and hold 150mph., one 6,000 hp locomotive at each end.  When they go "throttle up" at Westerly after clearing the last Grade Crossing, it does take time to build up to 150mph by Kingston.

  To pull enough power from one pantograph riding one wire at 150mph, is it possible, don't know.  If you were to double the size and weight by combining two locomotives into one???  Don't know, what did the Spec. say.  The French and Canadians know a lot more about this type of train than we do.

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Posted by tomikawaTT on Thursday, July 10, 2008 4:05 PM
 gardendance wrote:
 beaulieu wrote:
 passengerfan wrote:

I still do not see the need for Acela to have power on each end.

Finally Acela needs both power cars to have enough horsepower to make the schedule. 

beaulieu: I'd tend to agree with you. TGV and Shinkansen have power cars at both ends, and I expect the general consensus is that they are the epitome of high speed rail.

The Shinkansen trains have CABS at both ends - and powered axles under EVERY car.  That's why they accelerate like scared rabbits.

At a somewhat lower speed, JNR (pre-privatization) DMUs had powered axles under every car, both ends - with two notable exceptions, both on the highest-speed train sets.  The KiHa82 class cab cars had one engine driving the train and the other (at the cab end) driving the HVAC package over the front truck.  The SaShi80 class diners (specifically designed for and matched to the KiHa80 class trains) had no powered axles (presumably to keep the engine vibrations from disturbing the diners.)

Interesting aside - when modeling an abbreviated KiHa80 class DMU train, the only places where a power truck won't intrude into passenger space visible through the windows are at the cab ends of the cab cars and the kitchen end of the diner - precisely the places where the prototype train DOESN'T have powered axles...

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Posted by passengerfan on Thursday, July 10, 2008 5:21 PM
 tomikawaTT wrote:
 gardendance wrote:
 beaulieu wrote:
 passengerfan wrote:

I still do not see the need for Acela to have power on each end.

Finally Acela needs both power cars to have enough horsepower to make the schedule. 

beaulieu: I'd tend to agree with you. TGV and Shinkansen have power cars at both ends, and I expect the general consensus is that they are the epitome of high speed rail.

The Shinkansen trains have CABS at both ends - and powered axles under EVERY car.  That's why they accelerate like scared rabbits.

At a somewhat lower speed, JNR (pre-privatization) DMUs had powered axles under every car, both ends - with two notable exceptions, both on the highest-speed train sets.  The KiHa82 class cab cars had one engine driving the train and the other (at the cab end) driving the HVAC package over the front truck.  The SaShi80 class diners (specifically designed for and matched to the KiHa80 class trains) had no powered axles (presumably to keep the engine vibrations from disturbing the diners.)

Interesting aside - when modeling an abbreviated KiHa80 class DMU train, the only places where a power truck won't intrude into passenger space visible through the windows are at the cab ends of the cab cars and the kitchen end of the diner - precisely the places where the prototype train DOESN'T have powered axles...

Chuck

I understand why the Acela trains have a power unit at each end it just seems to me they could put more cars between the cab ends. They need more capacity on the Northeast corridor and twenty Acela trainsets are know where near enough as the gas price crisis deepens. Since the trains only achieve 150 mph for one short stretch of track north of New York maybe additional cars could be added to those trains operating south of New York. For all of the money spent on Acela I just feel we should get more bang for the buck.

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Posted by oltmannd on Friday, July 11, 2008 8:03 AM

 ndbprr wrote:
Any time the crew is inchs from the font of the vehicle there are going to be more injuries than if they are not if for no other reason then that is the crumple zone.  The PRR streamlined the last of the P5a engines because of a crew being killed in a box cab.  That is the reason for the cab location on a GG1.  Now if a crew could be seriously hurt in a cab built with 1/4" or thicker plate and a cast steel underframe I think I would opt for another location if I had a choice.  Wouldn't you?

How often and at what cost are the two issues you are ignoring.

Operating at 50 mph is safer than 60 mph, so why not always operate at 50 mph max?

Operating at 40 is safer than 50....I doubt there would ever be a fatality if trains operated at 5 mph max, so why not chose this as max speed?

At the same time the PRR converted the P5s into P5as, they continued to field a fleet of MP54s operating over most of the same territory (plus on the LIRR), allowed the PRSL to replace locomotive hauled trains with RDCs, and pursued new MU cars for NY, Phila and intercity sevice. 

Also, "crumble zones" are almost completely irrelevant in North American frt locomotive design.  Crumble zones are energy managment systems.  There is too much energy in a frt train operating mainline speeds to manage using crumble zones.  Unlike automobiles, deadly rates of deceleration rarley occur in derailments or collisions.

 

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Posted by DMUinCT on Friday, July 11, 2008 9:01 AM

   Passengerfan, you are right!

  True, South of Boston and southern Rhode Island is 150 mph track, but much of the line is 135 to 140mph limit.  Most trains run through Boston to Washington, station stops are short, even in New York, they can not take the time to add or remove cars and keep it a 6 + hour run.

   Acela, alone amoung bullet trains, have standard 8 wheel cars coupled together.   If needed cars CAN be added.  If a problem developes with one car, it can be removed from service and even another car substituted.

A close look at a car, note the wheel encoders, air springs, the Rescue Windows, and yes, the Acela Cabs ARE fully armored. 

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Posted by Paul Milenkovic on Friday, July 11, 2008 11:44 AM

Last I checked, the Japan Shinkansen used conventional 8-wheel coaches without articulation -- they may be semi-permanently coupled into pairs to share electrical equipment.  I also thought the Metroliners had an A end with a cab and a B end without and that they were connected in pairs with back-to-back B ends.

The French TGV famously uses articulation -- Jacobs or Jakobs bogie it is called in the industry when the articulation shares a 4-wheel truck.  That is in part a weight-saving measure as the wheels and trucks are a heavy item.  In France, they have wheel shops that can take entire TGV trainsets and do the maintenance on them without taking them apart.

Southern Pacific back in the day had articulated "chair cars" and diners.  Just because you articulate something doesn't mean the whole consist has to be one permanantly-coupled unit.  You now have articulated spine cars and double-stack well cars in intermodal freight service, and the railroads had been experimenting as to how big a permanently-coupled chunk is desirable, a tradeoff between savings in having fewer switchable cars vs having a big string bad ordered all at once.

The TurboTrain was articulated and guided-axle and all of that, but the design had retractable clamshell doors to expose couplers and a passageway at the streamlined ends that allowed joining TurboTrain sets in multiple.  They never had enough TurboTrains in service that this was done in practice, although I saw one picture from Canada where they retracted the clamshell doors to hook on an FP-9 locomotive when they had mechanical trouble with the turbine propulsion.  The account was that the TurboTrain was so light that the FP-9 provided quicker acceleration from a standstill than those turbines, although the top end speed would be reduced form 150 MPH considerably owing to traction motor gearing.  The TurboTrain could have been successful as locomotive-hauled equipment, just as the Amfleet coach is an unpowered Metroliner

If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?

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Posted by DMUinCT on Friday, July 11, 2008 1:40 PM

  Oh yes, The "TurboTrain", built by my former employer, United Technologies (AKA United Aircraft).  Based on the Pullman-Standard "Train X", Pratt invented a "Pendular Suspension System" that was very successful.   Patentes TALGO S.A. later adoped it as "TALGO Pendular".

  UT's Pratt & Whitney division planned a 3 unit train with a power car on each end, wind tunnel tested.  Each power unit would have 2, 3, or 4 P&W PT6 turbine engines, designed and in use in Turbo-Prop aircraft, direct geared to the two front axles.    Each turbine weighted only 300 lbs yet put out 550 hp.  Each Power Car could be rated at 1,100  1,650 or 2,200 hp.  Turbines could be added or removed via side doors by field personel.    Each power car had 28 seats below and 24 seats in the "Vista Dome" located over the jet engines.  Design speed 160mph. Two trains could be coupled together with the "Clam Sheel" connection. One crew up front would then control all four Power Cars (one at each end and two in the middle)

  U.S. DOT ordered 2 three car train sets with 3 turbines in each power unit. Top speed was geared down to 125mph do to New Haven Railroad track condition.   Canada ordered 5 seven car "TurboTrains" to be built by the Montreal Locomotive Works.   As I remember, Canada had problems, 5 intermediate cars, snow clogging the engine intakes.   As for the Boston to New York run, Turbo equipment availability was 91.7% vs coventional equipment at 84.5% (but the Turbos were new, the New Haven was old).  Amtrak later added more intermediate cars bought as surplus fron Canada.

   

Don U. TCA 73-5735

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Posted by HarveyK400 on Friday, July 11, 2008 4:36 PM
If I'm not mistaken, the Xplorer and Turbo Train suspension is markedly different from the TALGO Pendular, as discussed in a previous thread.
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Posted by HarveyK400 on Friday, July 11, 2008 5:22 PM

I agree with you to a point about adding cars to increase capacity.  150 mph speed is unnecessary and not sustained for any significant distance; but Amtrack got a lot of marketing mileage out of only a few miles.

For shorter base service trains, a cab control coach would be more sensible with all the horsepower in the locomotive.  The same Acela nose and safety cab could be built on the end of a coach, much like the previously mentioned X2000.  The X2000 runs at 125 mph with 4-5 cars, a cab coach, and an electric locomotive.  A similar Acela train could have 352 seats.

The Southwest Airlines model is to vary frequency to match demand with fixed consists, in this instance a 737 aircraft.

Amtrak has the option for back-to-back Acela Locomotive+coach blocks without a cab coach with as many as 14 cars with reduced drag having roughly 680 coach and 140 business class seats for over 800 passengers and still accelerate quickly to 125-135 mph.

The next issue is whether pricing makes optimal use of capacity given the cost and revenue for the train. 

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Posted by DMUinCT on Saturday, July 12, 2008 9:05 AM

  Acela, First and Business Class only.   In the Northeast Corridor, Amtrak does run a fixed consist Acela every hour (much like Southwest Airline).  

  They then run Locomotive hauled Amfleet Reserved Coach and Business Class trains every 2 hours.

   Do they need more?

Don U. TCA 73-5735

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Posted by HarveyK400 on Saturday, July 12, 2008 12:03 PM

This discussion of Acela service utilization/capacity more properly belongs in the current thread on energy consumption; but here we are.

The initial point was, I recall, that some of the hourly Acelas carried light loads while business was turned away or diverted to other trains.  A more flexible schedule, ala Southwest, would be more efficient with.  Recently advertised Southwest schedules for various destinations are not on an hourly, clocker, schedule.

You ask if this [Amtrak] needs more.  Service would depend on the demand for travel and the train's capacity.

I had forgotten that the Acela is a premium First & Business service.  It can't be very efficient; but passengers are paying for the priviledge.  It's interesting to see what Acela might do in terms of numbers it it had coach seats.

The next question is what utilization is achieved on the Regionals? 

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