Passenger

Jerry Pier:

Amtrak has an aversioin to gas turbines so if anyone ever suggested such a thing, continuity of employment would involved. A dual mode with catenary and gas turbine electric capability would increase locomotive weight by the turbine alternator unit and the fuel tanks. A scheme some of us thought of was to have a gas turbine electric (no pantograph) in trail from Boston to Penn Station and then use gas turbine power in the lead from Penn Station to WDC (letting the trailing electic locomotive push the train until exiting the tunnels). This would get around the performance limiting antique 25 Htz catenary and gain both time and reliability.The Bombardier Jet Train is ideally suited to the gas turbine task. The Acela's are over-powered anyway so it sounds like a winner, at least to me. .

A number of years ago, FRA estimated that replacing the 25 Htz system would cost at least 1  Billion dollars and upgrading the 60 Htz section from New Haven to Penn Station would cost a similar amount. This isn't a very sexy program so funding could be hard to find. The dual mode solution could be quicker and less costly

 What made me think of that is that supposedly back in the 90's GE made a presentation to Amtrak (and possibly some of the transit agencies) of a P32 Dual Mode unit with a pantograph rather than third rail shoes..there were, of course, no takers...New Jersey is in the process of designing some dual mode units with Pantographs;

http://en.wikipedia.org/wiki/ALP-45DP

I see your point about the weight issue..

They've been discussing high speed rail between St. Louis and Chicago for years and nothing has been done.  Of course, Amtrak doesn't own the rails out this way and getting the host RR's to sign

off on it is no doubt a problem. 

Sunnyland:

They've been discussing high speed rail between St. Louis and Chicago for years and nothing has been done.  Of course, Amtrak doesn't own the rails out this way and getting the host RR's to sign

off on it is no doubt a problem. 

Al - in - Stockton

CSSHEGEWISCH:

Note that both the FL9's and the P32's operate as straight electrics only when they aren't in the open air. 

Actually that was an operating decision (schedule) because at the time they were designed those units could only take 600V dc and apply it to the traction motors. .. The Dual mode DC units LIRR has also have that deficiency. Todays DC Traction motors use a higher voltage now so you cannot get enough power (slower acceleration and top speed) to the traction motors using third rail 600V. Those locomotives switch to the higher voltages from the locomotive alternator as soon as possible. 

AC traction dual or tri-mode mode locomotives.. AC traction locomotive systems can take any voltage (DC from third rail, DC from an alternator, or DC from a transformer rectifier) in and run that DC through the inverters and get any voltage and frequency out. Note: THOSE Inverters are one of the big additional costs of AC traction over DC. Do any of you in the power industry know if those costs are decreasing? Today's EMD and GE use different designs with EMD using two inverters and GE 6 smaller ones. Inverters and AC motors are very reliable so dispatch reliability is improved.

The Dual mode locos mentioned above that NJ Transit is going to buy probably cost alot because 6700HP (max 5300 when full HEP applied) on 4 (?) axels may require the design of new inverters and maybe AC traction motors. Imediately rectifying the AC before any locomotive use enables use of 25Hz or 60Hz with only a transformer tap for each voltage. i.e. if it was 12.5V 25Hz or 60Hz no other item in the loco would be needed

Note: Two Catepillar prime movers 2250HP each. Max speed 100MPH. Max speed from wires 125 MPH. Two inverters. 

I'll admit that I have not read every post in this thread, but might there be a marketing problem?  Let's start with the name...

My suggestion for a much-needed revival is Metroliner !!!  I feel ashamed to even type that other name being used for NEC express trains.  It sounds like a body part upon which I am sitting... the place where you put a furnace... it might actually be able to "accelerate," but so what? 70 mph schedule times is sad... it is not "excellent," the first-class accommodations are mediocre...
 

I guess this is close enough to be on-topic:  Does the Acela actually "tilt" when it goes around curves?  Like the Pendolino or like the Swedish prototype, for lack of the exact specs Acela's "grandfather"?

I know the curves impose their own speed limitation but any tilting would tend to speed up the schedule at least a little, wouldn't it?   And reduce the passengers' attempts to steer the train with the muscles of their diaphragm? 

oltmanned

The Turboliners are double ended. To reverse, the crew just moves from one end to the other. This happens twice on every Schenecady-Penn Station trip

Running through to WDC would be no problem operationally but it would require more equipment or a reduction in frequency. The oother problem is that the RTL's, without the catenary speed restriction would probably beat the Acela, a definite no-no.

The piece of track between Princeton Jubction and Brunswick used to be good for 160 mph. The RTLIII's could zip along rhere at 125-140 mph.

Jerry Pier

Much as I think that turbines are cool, I am not so sure that turbines would beat electrics on end-to-end schedule keeping, certaining not for limited express trains making intermediate stops and perhaps not even for express trains.

Apart from the arguments of electrics vs motor trains and Global Warming and where-do-you-get-the-fuel-for-electricity, the one advantage of electrics is nearly limitless torque and HP.

Turbines, on the other hand, may not be HP limited on account of weight -- you can get lots of power in a small and relatively lightweight package.  They are limited in terms of HP rating so as to not have outrageous part-load fuel consumption.  The proposal to use regenerators or recuperators mitigates this effect some at the expense of increased weight and increased package size.

In railroad applications, your "cruise" HP requirements are small compared to what you could use if you could have it for acceleration to restore speed after stops or after slowing for speed restricted zones.  The is kind of the opposite of the helicopter or perhaps even ship application where close to max power is required at your cruise speed.  Jet airliners, on the other hand, have a takeoff thrust requirement that is multiples of cruise power, much like trains, but jets climb into the thin air at high altitudes to naturally reduce the power output of the engines without throttling them to reduce efficiency.

Again, in the railroad application you can mitigate these in several ways.  One is using turbines on lightweight but high speed trains so that the cruise power is a higher fraction of max power.  This is one way in that the United Aircraft TurboTrain had an advantage because it used aircraft-style aluminum construction to get lighter weight than most other trains.  Having track speed restrictions works against efficiency here, so perhaps the best use of the TurboTrain would have been to run it flat out between NYC and WDC instead of on the speed-restricted NYC-BOS run.

Another way is turning turbines on and off as needed.  The RTG/RTL's used a pair of turbines, one in each power car, and at "cruise", one turbine was reduced to idle.  Apparently this type of "hot standby" of one turbine used less fuel that keeping both turbines at reduced load, and I am guessing that idling the one turbine was better than simply shutting it off and restarting it -- perhaps because of thermal cycling, perhaps for the convenience of  not waiting the full 90 secons to restart it.

On the other hand, why could a turbine not be shut down in cruise, and the crew could push a button to restart that turbine when pulling into a station stop so the turbine would be ready to go at the schedules departure time.  One can readily anticipate restarting a turbine 90 seconds in advance of wanting to leave.

Maybe the thing to do (I am sure Jerry has thought of this or proposed it at one time or another) would be to put the regenerator on one of the turbines, to give it max flexibility in power level, and put the second turbine into a start-stop mode.  Has anyone thought of a kind of hot standby where the turbine is spinning at a rate below a self-sustained idle, but the turbine blades are kept at temperature to reduce the stresses of thermal cycles?

Jerry Pier:

oltmanned

The Turboliners are double ended. To reverse, the crew just moves from one end to the other. This happens twice on every Schenecady-Penn Station trip

Running through to WDC would be no problem operationally but it would require more equipment or a reduction in frequency. The oother problem is that the RTL's, without the catenary speed restriction would probably beat the Acela, a definite no-no.

The piece of track between Princeton Jubction and Brunswick used to be good for 160 mph. The RTLIII's could zip along rhere at 125-140 mph.

Jerry Pier

That's how I remember them running in and out of GCT and it's how the Keystone trains must be configured, too.  They had 1/2 the seats facing each way.  Looks like they don't do this with the Acela.  All the pix I can find show all the seats facing one way - they must turn the trains at each end of the run.  It would be a pain to have to spin them all, but maybe they do this.  Anybody know?  Having to turn the trains would be a real headache in NYP and DC acc't the congestion in the East River tunnel and Union Station throat.  They must have to turn the Empire trains at Sunnyside now. 

For a company that's screaming about equipment shortages, not getting thoses RTLs back running is a criminal waste.   

al-in-chgo:

I guess this is close enough to be on-topic:  Does the Acela actually "tilt" when it goes around curves?  Like the Pendolino or like the Swedish prototype, for lack of the exact specs Acela's "grandfather"?

I know the curves impose their own speed limitation but any tilting would tend to speed up the schedule at least a little, wouldn't it?   And reduce the passengers' attempts to steer the train with the muscles of their diaphragm? 

On my journey, the tray tables were defective, letting food and beverages slide into our laps.  If these trains were the "prototypes" for a new fleet, that would be okay... but we ordered no more,  the plant has closed and all the skilled workers are dispersed.

Paul Milenkoovic:

When the original RTL's were upgraded with a Turmo 12 (1608 HP) replacing the Turmo III (1139 hp) on one power car and leaving the Turmo 3 on the other Power Car, the intent was to use both turbines for acceleration and then shut the smaller one down. This kept the Turmo 12 at or about full power and so improved fuel consumption. Tests confirmed that this was viable on the Albany-NYC service. Typically, the enginemen were nervous about restarting the Turmo III so it was left at idle. Not as good as planned but still an improvement. Thermal cycling must always be considered but this can be managed. The RTL III's have a TM1200 (1608 hp) in each power car, either of which can handle the train by itself. Both can be used to accelerate if desired, particularly if you are reaching for speeds above 125 mph.

I'm all for recuperation but it would be better to use it on both turbines to equalize the service times. As I have mentioned previously, a recuperated TM1600 was developed to direct drive a 2000 kw permanent magnet alternator. It's specific fuel consumption matched a good diesel over the useful speed range. Unfortunately, the builder chose to get out of the  industrial turbine business.

Honeywell also did a paper study of recuperating the 5000 hp TF50. This showed  similar results. Makes you mouth water.

Jerry pier

Question :  Who on this planet is operating turbines now?? If so why? If not why?

 Our nations's ability to deliver high-quality passenger transportation is only limited by our attitude, not curves or power sources. 

 Q:"Who on this planet is operating turbos?  Why?"

A: All the airlines, because they are lightweight and reliable.

 There has been no improvement in NEC express service because we have a bad attitude about an aging train with an ugly name.  In comparison, Japan had 180 two-coach sets for opening day of the Tokyo - Osaka Shinkansen on October 1, 1964; by 1977, there were 2,352.  The condition of the NEC is shameful.  

Maglev:

 Our nations's ability to deliver high-quality passenger transportation is only limited by our attitude, not curves or power sources. 

 Q:"Who on this planet is operating turbos?  Why?"

A: All the airlines, because they are lightweight and reliable.

 There has been no improvement in NEC express service because we have a bad attitude about an aging train with an ugly name.  In comparison, Japan had 180 two-coach sets for opening day of the Tokyo - Osaka Shinkansen on October 1, 1964; by 1977, there were 2,352.  The condition of the NEC is shameful.  

The ability to deliver high speed rail in this country is more a function of the money our representatives in governement are willing to spend. It don't come cheap, or even moderately expensive.

The airlines use turbines as a thrust engine, not a torque engine, and run for long periods at near the maximum RPM. Not feasable for railroad operation. And can you imagine being in the lower level of GCT when a turbine engine comes in. I worked 20 years on the flight line at McGuire AFB, and you wear ear protection ALL the time. And that was outside where the sound didn't echo as much.

Unlike European or Japanese passenger runs, the North East Corridor shares the track with freight trains, even though most of the mileage is owned by Amtrak or commuter agencies. Not a suituation that's conducive to true HSR, or one that's likely to end soon.

The Northeast Corridor trackage is about 49.48% commuter and 49.49% Amtrak.  Although there is freight useage it is so minimal at this time it is almost negligable.