I'm new to this forum, but thought I'd try a reply on your post.
There are many things you can do if you really want to - but would light-rail at 100 mph be useful? Now, that assumes the the line would provide similar service as do other light-rail lines (I can think of ones in Sacramento and Portland), where stations are relatively close as compared to heavier rail. By the time the train was up to 100 mph it would be time to stop, sometimes. Yet, the systems I rode in Sacramento and Portland seemed like they had no problem with speed when on a tangent and away from intersecting traffic. Their acceleration and decel were also comfortable for passengers.
One example that's close to what you described is the Talgo the operates between Eugene and Vancouver, BC. It's a one-level train-set that leans into curves, like a bike. When it's getting out of the station, at slower speeds, etc., it can be kinda bouncy. At speed it rides pretty smooth. It operates on track designed for freight rail. The Talgo is supposed to be able to hit at least 120 mph, maybe more, but it purrs along at about 79 mph.
Don't know about costs. I just figure that it depends on the customers being served and the substantive safety / operating conditions along the desired route.
Jock Ellis Cumming, GA US of A Georgia Association of Railroad Passengers
I would think that it is possible, but I doubt it would happen. Also to get any real advantage of high speeds, you would need a longer run that Minni to St Paul. The extra speed really wouldn't be worth the cost, and would not get you there that much faster.
Bert
An "expensive model collector"
You could design "light rail" to go to bullet train speeds, but it would no longer serve a transit funciton since staring and stopping distances would put the stations too far apart.
The Karlsruh dual-mode (High voltage ac and regular dc) tram-trains regularly share tracks with the railroad's high speed trains and then also with regular dc low-floor tram cars on city streets. It is a modern and extensive interurban system with a regular streetcar system at its core.
The North Shore regularly ran 90mph and also ran on Milwaukee city streets. Overall average speed was two hours Chicago - Milwaukee, about 90 miles, or 45 mph for the express trains using the elevated and slower operation in Chicago and streetcar tracks in Milwaukee.
Modern light rail usually averages about 22 - 36 mphs overall with frequent stops included.
Although it's rapid transit and not light rail, the single-unit PCC rapid transit cars used by CTA when the Skokie Swift began operation were equipped with field taps to raise the top speed of the cars from 55 to 70 MPH. Since the Skokie Swift is only about 5-6 miles in length, the extra speed resulted in a time savings of only about a minute. The CTA decided that the extra speed was not worth the extra maintenance expense and removed the field taps.
Higher top speeds in light rail may be technically feasible, they're just not practical.
Most light rail in the US is limited to 55mph by regulation I believe.
Also there is probably a current practical limit for operation of low floor cars. Without the solid center axles, some cars feel like they are hunting across track at 55mph. I have noticed this in Portland OR. The older high floor cars with regular solid axles seem to run smoother at those speeds on the same tracks.
Ron
Hold on to that strap!!! 80 mph was normal on the Interurbans in Albany-Scectadady-Saratoga NY.....And once out in open country the trolley guys just opened up that throttle!!Indy Interurbans went 80-90...and of course the North Shore from Chicago-Milwallkiee was 100 mph on a slow day..
The RTA Cleveland OH Italian Breda LRV cars are geared for 80 mph but can only do 45 due to track conditions and siganal blocks....The recent challeges to them has been climbing steep grades built into the right of way coming out of the Cleveland River Flats at 7% grades...
For what it is worth, the Portland Oregon's Light Rail system, which we call "MAX", is limited to 55 MPH but is capable of doing 100 MPH.. The TALGO which runs from Eugene to Seattle and hopefully beyond, does bounce a little at slow speeds in the yard, due to rails and switches. The top speed for TALGO is limited by the rail speed., in the section it is running.. That top speed is 79MPH. Hope this helps.
With regard to the TriMet MAX Type 1, Type 2, and Type 3 vehicles, NONE of them are capable of 100mph with their current gearing, and even if regeared, may not make 100mph. They are geared for 65, but may be hard pressed to make 62.
Also the issue of truck hunting at speed as previouly mentioned, cannot be ignored. I believe that the Type 1 cars, when new, did have a hunting problem that was fixed. It may be still a minor problem of the Type 2 and Type 3 cars. The best place to feel hunting in these cars is seated over the center truck of a car in the Washington Park Tunnel.
I think so you could link them together? You just talk to the state about it and they might build one for the connecting cities and states that you may connect together
As a child in Philly I remember several thrillingly high speed rides on the Red Arrow Lines interurban trolleys to the west of Philly. I understand that SEPTA still uses those same right of ways for, I believe, regional rail. Is this correct? If so, what kind of speeds do they hit?
Jack
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
Morning everyone.
From what I have read and seem from just skimming, I think I need to bring up the Dallas Area Rapid Transit system (DART). Our light rail trains are rated over 120 mph. Although these light rail trains mainly run in the city there main line max speed is 65 mph. There is no reason at this time to ever get the light rail up to 100 mph. From riding the Dart system it is a great thing to have, but with the operators that are operating the trains, I would not trust riding with some of them. Even at 65 and 70 mph the light rail trains are ruff. I am not sure what the cause for this is, but I dont trust them over 70 mph. I am currently working for DART, and plan to go and start operating the light rail trains, so I will up date more often.
HiWire wrote: Most light rail in the US is limited to 55mph by regulation I believe. Also there is probably a current practical limit for operation of low floor cars. Without the solid center axles, some cars feel like they are hunting across track at 55mph. I have noticed this in Portland OR. The older high floor cars with regular solid axles seem to run smoother at those speeds on the same tracks.Ron
There is one piece of track on the Rotterdam, the Netherlands, tramway system on my regular commuting route where an operator of RET's Alstom Citadis type LRV's can go easily 70 kph and can push 80 if he or she has a mind to do it (the speed scale goes into the red after 80).
The Citadis type cars have a low floor and accelerate and decelerate rapidly. I have not detected any notable hunting. This in contrast with the older high floor cars of RET series 700 or 800 (build and rebuild by BN of Belgium I believe). They shake and rattle on that piece of track when running fast and I always have the feeling they will come of the track.
Rather than topspeed, wouldn't quick acceleration and deceleration be more usefull?
greetings,
Marc Immeker
Generally, light rail tries to save time by quicker acceleration and deceleration. Typically, the industry recommends 3 miles per hour per second as the upper limit for passenger comfort. In other words, it would take 10 seconds to get to 30 (or ten seconds to stop from 30 mph). However, there is only a certain amount of horsepower, most light rail vehicles can't reach 60 mph in 20 seconds. It's more like 40 or 50 seconds.
Speeds above 50 mph are usually only practical if there is a private right of way (no grade crossings), a long distance between stations (2+ miles) and double track (single track may be practical for the last 5 miles of a line.) But, Light Rail is generally driven by costs, and grade crossings are a lot cheaper than tunnels or elevated structures. And, costs dictate that a new light rail vehicle be similar to existing ones. Which are usually 60 MPH, max.
One of the readers mentioned Karlsruhe, in Germany. They indeed run light and heavy on one set of rails.
The Stadtbahn (city trams) go in town and out to the suburbs and beyond. We were clipping along around 150 kmh (90 mph) through Rastatt to Baden-Baden. The Regiobahn (regional) do not stop at all the small stations like the S-Bahn does. They move out real well.
A side note, I rode the IC and the ICE trains a lot for the month I was in Germany. One ICE went from Frankfurt to Mannheim to Saarbrucken and then to Paris. The digital reader was showing a sustained speed of 280 kmh (175 mph) through France. That was rocking!
In Prague, and then back to Mannheim, the EC trains went along around 120 mph. Europe has been maintaining and upgrading for years, from the S-Bahn up to the ICE-5. They look to the future, while here in the US we complain about the traffic.
Munich, Hamburg, Berlin, and a few other cities have remarkable S- and U-Bahn (subway) systems. Karlsruhe Modell (German for model) have been the examples for a lot of cities getting into urban rail. It works well when politicians stay out of the way.
Enjoy the rails.
top speed of a normal pcc under load was about 48 mph. in additon to fast acceleration and braking, the latter 4.5 miles per hour per second using the magnetic track brakes, for emergency braking, the pcc was somewhat faster in top speed than most of the older cars it replaced. A typical double-truck birney or other four motored lighweight had four 35hp motors, while a pcc had four 55 hp motors and was just as light if not lighter. a typical double truck lightweight had a top speed of about 35 or 40 mph. then there were the vast fleets of old wood semiconvertables and convertables with only two motors, having a top speed of about 25 or 30 mph. single-truck birneys were somewhere between the two. of course cars designed for interurban service, like the bullets, the red devils, and the indiana high speeds, plus some older heavier cars like the north shore's, were far faster, having balancing speeds of about 80 mph, and having possibilities of even faster running under the most favorable conditions.
does anyone know for certain if the interurban pcc's, pittsburgh railways' charleroi and washington lines, and the pacific electric, had different gearing for higher top speeds and slightly less acceleration? trucks were slightly different. the red arrow postwar lighweights, with pcc style bodies but without resilient wheels, pcc control, and with mcb type drop equalizer trucks, built by st louis in 1949, were not pccs but used the same motors. but their gearing was different and they had a 55 mph top speed.
Going 100 MPH between Mpls and St.Paul might be possible, but wouldn't make much sense, since they're only about 9 mi. apart (downtown to downtown). There probably aren't going to be any nonstop trains, trains will be making several stops along the way (as they do now between DT Mpls and the Mall of America).
High speed makes more sense for interurban runs - Chicago to Milwaukee for example.
Maybe I shouldn't butt in after all these months of inactivity on this thread, but I think in some of the posts above, a mixing of terms between what constitutes a trolley physically, where and how often it can stop, and what constitutes a proper trolley speed is muddling things a bit.
Take the Karlsruhe, Germany trolley system, which I've ridden. It's a nice set-up even if the fares are a little stiff. Or take their three-car conjoined trainset cousins in Vienna*. Or take San Francisco's Muni Metro, or the San Diego trolley, or L.A.'s east (Blue? Line--not the subway). Also take Toronto's streetcars (I don't know if Canadians officially use the term "trolley" car, though I feel sure they'd recognize it. The trolley is just a part of the main, the pole that gets the juice from the catenary down to the motor, which makes it a kind of living anachronism in the day of the folding pantagraph for even local traffic). If you asked most Americans what a "trolley" is, probably most of them would think first of the clang, clang, clang version. But "trolley" is this country has slowly come to mean as well "beverage cart" as on an airplane, or (and this really kills me) those rubber-tired tourist "trolleys" that are really just open-air buses in disguise, hauling out-of-towners about the downtown area. Don't even get me started on the pseudo-Britannic use of "tram" in places like Las Vegas. *The German word for streetcar or streetcar system is "Strassenbahn," literally "street (rail)way." I don't know if Siemens or ABB or the other European manufacturers have had to concoct a more modern word; but "Strassenbahn" will hold no matter how antique or modern the rolling stock is. Besides, they've used pantagraph collectors, just like electrified rail lines, for generations; so they don't have to worry about that metonymy "trolley."
The Karlsruhe system runs from the country into the city. Vienna's "trolleys," like those of the Muni Metro, duck underground for a while downtown (or at busy intersections) and then emerge to run on the streets like the streetcar systems any good-sized American or Western European town had by ca. 1920. San Diego is an excellent example of what a (primarily) German expertise can do for us here at home wish a fresh start and with about half the stops of the buses they replaced eliminated, in favor of open-air stations with ticket machines (and of course running times much faster). Canada hasn't given up on the use of the term "streetcar," and I'm curious to see how much, physically, the proposed light rail lines are similar to the TTC's vast network of streetcars. The Blue(?) L.A. line goes that one better with dedicated and usually elevated rights-of-way and more elaborate stations as well as automatic ticketing.
Here's my point: technique and tradition may argue for different semantics, but all the cars or trainsets above are brothers under the skin. They are "light rail" in the sense of being relatively lightweight on the rails and therefore not needing the well-over-100-lb. track that is now pretty much the norm for conventional passenger and freight. Also, they all use the same or very similar DC induction motors, which are best at overcoming inertia. Another way of saying this is that streetcars, LRV's or whatchamacallits haul off blazingly from a full stop (0 mph), but gradually lose that efficiency as speed grows, to the point where somewhere around 45 mph (metric 80 kph), they reach an effective top speed. That's probably why some of the above posts offer these speed ranges or their approximates as canonical limit of forward speed. Pre-cybernetics, the motorman's controller would usually define "full speed" as something below the highest possible cruising speed, in order to avoid overheating. In this day of solid-state and cybernetics, I suspect any such governing is more subtle and sophisticated. But this genre of rail public transit (and also most trolleybuses) can push you back in your seat after getting the green light but eventually strain their utmost at parkway speeds or less.
That's why Toronto's streetcars are still plying the streets. From the Sixties until the mid-Nineties, a regular TTC streetcar, even PCC vintage, could race the fastest car from one traffic light to the next -- and would always win, at least until the Porsche Cayenne came along about ten years ago. That's a Porsche in top condition with manual gears and a professional driver. But as good as 100 percent of the time up there, it isn't the streetcar that slows traffic; if anything, its the traffic slows the streetcars. It will be interesting to see how different Toronto's proposed LRT electrics will resemble the by-now "classic" streetcars of the TTC.
Again, in our case it's not so much the need creating the technology as the technology determining the need, or at least begging the kind of infrastructure speedy and efficient light rail demands. Something with a quick getaway but with the ability to stop fairly easily -- but for the sake of overall speed and the passenger's tummies and lumbar vertebrae, not too often. You can see this very clearly in the San Diego system as an improvement over buses and in the L.A. Blue(?) line, which behaves as much as possible like a Elevated or a commuter railway with its relatively few stops. Again, trolleybuses also have much the same energetic starts but middle-range bog down, because they use similar motors.
By these criteria, of course, other "light-rail"-ish candidates emerge: The Shaker Heights Trolley. NJT's diesel LRT. Moreover, again IMHO it's not so much the need creating the technology (ninety percent of what we know about traction we knew by 1915) as the technology determining the need, or at least begging the kind of infrastructural format to offer the most utilitarian combination of speed, service and stopping-places. Something with a quick getaway but with the ability to stop fairly easily -- but for the sake of overall speed and the passenger's tummies and lumbar vertebrae, not too often. You can see this very clearly in the San Diego trolley and to a lesser extent in the others light-rail getups. Also in trolleybuses to some extent because they use very similar motors.
Now if some transit official claimed that his jurisdiction's pantagraph-updated streetcar type of LRVs can reach a speed of 100 mph, he is mistaken. Even the New Jersey diesel LRT can't reach 100 mph. Perhaps he meant that the rail is so heavy it could keep (the right kind of) a train on the tracks at such high speeds. Certainly all manner of rapid-transit, and commuter equipment, gets assigned to the "heavy rail" category. On the one hand, we have the lighter kind of heavy rail: the Brilliners, current CSS&SB interurbans, Chicago's "L", Vienna's "Stadtbahn" ("city rail," which is also elevated and which reminds us that certain kinds of rapid transit, like L or Stadtbahn, are not a strictly suburb-to-city affair). Usually (not always) it is possible to distingish them from heavy heavy rail (BART and the Washington Metro, both built by Bechtel; the New York subway system; Cleveland's rail link to the airport).
Notice that the lighter type of heavy-rail has the advatages of stopping quickly and efficiently relative to the really heavy stuff, but they can't stop all that often for fear of compromising speed, an argument well-made in earlier posts to this thread. Light heavy-rail can cruise much faster than LRT: it is no surprise that the types of motor they employ include legendary modes like the Brilliners or the Chgo-Milwaukee Electroliners, which could hit 85 without breathing hard back in the late 1930s. Even so, it's still a challenge to get this kind of m.u. above about 85-90 mph; notice that in this country in the late 1960s the (heavy heavy rail) Metroliner rarely succeded in cruising at 110 mph with the occasional burst to 125, its stated intention. You'll also notice those original Metroliners were adaptations of suburban m.u.'s, with no locomotive, and their points got blasted so often that it wasn't unusual to see Raymond Loewy's 1930s deco-style GG-1's hauling a fritzed-out Metroliner m.u. or lead unit off to repair.
The advantages of an interurban are that even though it shouldn't stop as often as a streetcar, it can when necessary (think of South Shore Line's street running in Michigan City). And, over a distance, their superior speed (which can reach almost twice that of the simple-trolley category) comes to dominate over time and distance. I think of the South Shore Line's voluntary flag-stops in the dunes segment of the rwy are brilliant: "Passengers use light at night," so no more time is wasted accelerating and decelerating than is necessary.
Another similar but fun argument is to get into distinctions between commuter-based heavy rapid transit (BART) and railroad-based commutation (Metro-North, and notice that they both get energy from a shoe, so means of propulsion alone does not determine). Up until a year or two ago the (ex-IC) Metra Electric line from Randolph St./Chicago down to Governor's State University was the duckbilled-platypus of American rail commutation: fixed schedules but trains run more frequently than its other, diesel-based Metra brethren. Skip-stop or express service, though that could belong to either kind of heavy rail. Tickets bought from machines that were in essence an earlier generation of the "now you may pass" turnstiles like New York subways after the imposition of farecarding. But then Metra closed the ticket machines, brought in more trainmen to check the paper tickets that are rated by zone and can be bought from any Metra vendor throughout the whole system -- so that now, the IC-electric is simply the juiced version of any Metra diesel. - a.s.
Al, 99% of your posting is correct, but I must make one correction:
Up-to-date high speed electric locomotives, suburban mu cars, metro or subway cars, light rail cars, trams or streetcars, all today, use non-synchronous ac hysterises motors, just like the best (for heavy hauling tractive effort and high overload capacity) EMD and GE diesel locomotives. The main reason is no added maintenance for replacement of carbon brushes in the dc motors that have been familiar up to a few years ago . This is also true of modern trolleybuses and battery buses. Alstom, Semans, and Stadler (or Brown Brovori for Stadler) make these motors, also Nikki Shaaro in Japan. In the USA, the pioneer was Amtrak's AEM-7. Of course the Acela equipment uses it, also the latest CTA, Washington, Pittsburgh, etc. equipment.
Some use this motor in an inside-out manner built into the wheel as a wheel-motor or hub-motor. This is true of some Stadler equipment and some Alsthom equipment, and makes possible a 100% low-floor streetcar or LRV with a low aisle continuing between the powered wheels. Independent suspension of each wheel or virtual truck with a low bolster pvioting under the floor are both possibilities. Las Vegas' Max line has diesel electric articulated buses using this concept.
There is also a varient of this scheme with rotating permanent magnets instead of coils. The manufacturers of these motors are Energy Storage Systems in Derby, England, and Magnet Motor, in Pressburg, Germany. Trolleybuses and low-floor airport diesel electric buses in Europe are the main use but Energy Storage Systems makes a remote controlled tiny railroad shop switcher that is in wide use and is attemting to enter the railcar supply market.
daveklepper wrote: Al, 99% of your posting is correct, but I must make one correction:Up-to-date high speed electric locomotives, suburban mu cars, metro or subway cars, light rail cars, trams or streetcars, all today, use non-synchronous ac hysterises motors, just like the best (for heavy hauling tractive effort and high overload capacity) EMD and GE diesel locomotives. The main reason is no added maintenance for replacement of carbon brushes in the dc motors that have been familiar up to a few years ago . This is also true of modern trolleybuses and battery buses. Alstom, Semans, and Stadler (or Brown Brovori for Stadler) make these motors, also Nikki Shaaro in Japan. In the USA, the pioneer was Amtrak's AEM-7. Of course the Acela equipment uses it, also the latest CTA, Washington, Pittsburgh, etc. equipment. . . .
. . .
Daveklepper, thank you for bringing my early-Metroliner standard of knowledge more up to date. Things are starting to make more sense now . . . even though what I know about electricity could still fit in Reddy Kilowatt's left glove, I am slowly learning, in large part because of helpful advice from people like you. Thanks again for taking the time.
This reminds me that I ought to start traveling to check out the newer systems, now that I have more time. The theoretical often goes down better when it is preceded by the actual! Sadly, I don't think I've been on any public transit system post-MARTA: Tri-Met, the Miami system, Mpls., Calgary, St. Louis and so on -- all virgin territory --I've gotta to some of them!
Just for the [Hades] of it, does anyone out there know where the fastest American LRT lines are? My guess would be that the winner would have the latest technology and also the fewest stops en route -- or is there a clear winner here? Something to think about. - And since these preceding two paragraphs are really a new topic, I'm going to start a thread. I welcome and answer all I.M.s. -- a. s. (al-in-chgo)
I remember the Santa Clara Valley Transit Authority (VTA) light rail trains topped out at 70 mph on some routes, notably the route down California 87 from downtown San Jose, CA.
Here in Sacramento, CA, the Regional Transit light rail usually top out at 60 mph.
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