Sacto1985 Posted July 25, 2015 Share Posted July 25, 2015 And now, here's something interesting: a forward view video of the Caltrain Baby Bullet limited express service from San Jose to San Francisco, CA: Even though the video quality is not the best, it's very interesting to compare this against the many zenmen tenbou videos of passenger trains from Japan. Besides the obvious difference of right side running, note the train engineer blows the horn a lot more, probably because the Caltrain line--a former Southern Pacific rail line--is not grade separated like you get with many Japanese rail lines. Link to comment
gerryo Posted July 26, 2015 Share Posted July 26, 2015 I think it's always nice to have a train engineers view of the track, especially over long distances. I also think it would have been good to see a picture of the train we were "riding" in. Some of us here in the East do not know what CALTrain has for their customers. gerryo Link to comment
ToniBabelony Posted July 26, 2015 Share Posted July 26, 2015 Besides the obvious difference of right side running, note the train engineer blows the horn a lot more, probably because the Caltrain line--a former Southern Pacific rail line--is not grade separated like you get with many Japanese rail lines. I always wonder about that. So much honking going on in the USA with trains, although there are plenty of guarded/automated railway crossings, plenty of fences surrounding the tracks, etc. Are there really so many people crossing the tracks where it's not allowed? Link to comment
Mudkip Orange Posted August 16, 2015 Share Posted August 16, 2015 The speed around curves at the beginning is painful to watch. Hooray for federal standards for unbalanced super based off obsolete NH smoothsides. Link to comment
railsquid Posted August 16, 2015 Share Posted August 16, 2015 (edited) The speed around curves at the beginning is painful to watch. Hooray for federal standards for unbalanced super based off obsolete NH smoothsides. I understand almost every word in the second sentence (apart from "NH" - New Hampshire?) but what does it mean? Also, is a "Baby Bullet" something available in the junior ammo section at Walmart? Edited August 16, 2015 by railsquid 2 Link to comment
velotrain Posted August 16, 2015 Share Posted August 16, 2015 I also think it would have been good to see a picture of the train we were "riding" in. Some of us here in the East do not know what CALTrain has for their customers. Look at the passing trains at 3:35 and 6:20 - no doubt more later, but that's as far as I watched. Link to comment
Fenway Park Posted August 16, 2015 Share Posted August 16, 2015 The Baby Bullets use a Class 59 and more modern stock as opposed to the two trains seen @ 3.35 and 6.20 which have Class 40 older locos. Travelled on the line last year from San Francisco to San Jose and back to see the San Jose Sharks Ice Hockey. The last train back to San Francisco is held for 30 minutes if there is a skate off: That's service. Surprised the last train was also the more modern fleet and loco. Link to comment
bikkuri bahn Posted August 17, 2015 Share Posted August 17, 2015 (edited) note the train engineer blows the horn a lot more, probably because the Caltrain line--a former Southern Pacific rail line--is not grade separated like you get with many Japanese rail lines. Japan still has a tremendous number of grade crossings even on main lines with frequencies of a train every 2 minutes-some crossings 1m or less wide just for pedestrians or pedestrians/bicycle/motorcycle traffic. This is despite the continuous construction of replacement elevated lines- the difference is apparent when travelling in Europe, which has relatively few grade crossings, particularly on the main lines (well, at least in Germany/Switzerland). The fact that American engineers use the horn is that is a requirement/law to do so at every grade crossing (unless a quiet zone is in effect). In Japan drivers typically use the horn (briefly) only on a double track when a train on the other track is passing in the same vicinity of the crossing. https://www.fra.dot.gov/Page/P0104 Edited August 17, 2015 by bikkuri bahn Link to comment
Mudkip Orange Posted August 21, 2015 Share Posted August 21, 2015 I understand almost every word in the second sentence (apart from "NH" - New Hampshire?) but what does it mean? The faster you go around a corner, the more you get pulled to one side - i.e., centripetal force. This can be countered by tilting the tracks or road. The US Federal Railroad Administration (FRA) has standards for how far you can tilt a track, and for how much force you can have going around a corner. The tilt standards are called "balanced superelevation," because the track tilt balanced the centripetal force. The standards for sideways force are called "unbalanced superelevation," because the track isn't helping - you're feeling yourself pulled to one side of the car. The FRA standards for "unbalanced super", or how much lateral acceleration is acceptable, are some of the most conservative in the world. They are, for example, less than half of the standards for the French TGV, and about a third of what is permitted on some Spanish and German lines. These standards are the result of tests done in the 1950s on the New Haven Railroad. New Haven's 1950s passenger cars, called "smoothsides" (in contrast to the corrugated aluminum common in America at that time), were very lightly sprung, and tended to sway a lot on corners. Because of this, the passenger comfort levels recorded in these 1950s tests mean almost nothing in the context of modern equipment. However, because the results of these 50's tests on obsolete cars were written into federal law, we're stuck with trains that go very slowly around corners. Hence, "federal standards for unbalanced super based off obsolete NH smoothsides." The beginning of the sentence, "Hooray for," is simple sarcasm intended to express displeasure at the asininity of our rail standards. 3 Link to comment
kvp Posted August 21, 2015 Share Posted August 21, 2015 Low amount of superelevation also helps keep doublestacks stacked when a train stops on a curve. Europe doesn't use double stacks. On the other hand, any active air suspended set could lean in a curve and take it faster than heritage stock. Link to comment
Mudkip Orange Posted August 25, 2015 Share Posted August 25, 2015 kvp, I take no quibble with your propensity to respond to every post with a tangentially-related comment expounded with utmost conviction. Were you attempting to pick up a woman in a coffee shop, or perhaps competing to be the Republican presidential nominee, such brusque certainty would certainly accrue to your advantage. However, in this case, I must interject to point out that what your comment has nothing to do with what we're talking about. "Unbalanced superelevation" is not the cant of the tracks, but the force which trains exert on tracks of any given cant at any given speed. To whatever limited extent that the performance of doublestack trains should influence allowable speeds for passenger equipment, it ought to militate in favor of higher unbalanced super, since the North American freight network tends to be flatter than dedicated transit or high-speed lines. 1 Link to comment
kvp Posted August 26, 2015 Share Posted August 26, 2015 You talk about cant deficiency (http://en.wikipedia.org/wiki/Cant_deficiency), which is the part of the force that is not compensated with superelevation. The problem is two fold: First, the superelvation is usually less than in for example Europe (thanks to the double stacks), which means the same curve speed results in higher hoizontal force on the cars. The second is the maximal allowed force on the cars, which is lower than in Europe. The reason for this might be partially the heritage stock still in use (mostly the old diners) and partially the height of the roughly double stack high amtrak cars used on many routes. These two limits add up and result in a lowered maximal curve speed. This should not apply to dedicated and electrified passenger corridors and i think there are exceptions on the acela route for high speed trains. However an actively suspended (tilting) train could compensate for both and could have a higher allowed curve speed. Allowing higher speeds on curves with non tilting equipment could be ok, as long as there are no hertiage or double/high deck cars in the consist and the trackbeds are properly reinforced to counteract the horizontal forces on the track without superelevation. Link to comment
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