Freight equipment has long since expanded to 89' carlengths, but passenger equipment seems to have stopped at 84'-85'. There are enough proposals going around asking for new cars/designs...why has no one (except Colorado Railcar) moved to the longer car?
Kevin C. SmithFreight equipment has long since expanded to 89' carlengths, but passenger equipment seems to have stopped at 84'-85'. There are enough proposals going around asking for new cars/designs...why has no one (except Colorado Railcar) moved to the longer car?
When going around curves the center of longer cars swings more to the inside of the curve than do short cars - creating potential clearance issues with the overhang. If you notice among freight cars - long cars area several inches narrower than their 40 & 50 foot brothers.
Never too old to have a happy childhood!
For passenger cars, there is also the issue that the diaphragms at the end of each car have to line up to allow safe passage between cars, which is not an issue between freight cars.
According to one book in my collection (Drawings of Amtrak cars from ~1975), the CB&Q had a few pre-war cars that were 88' long.
Edit: Book was Amtrak Car Diagrams published byWayner Publications. Car in question became ATK 1008, was originally baggage-dormitory-coach when built in 1940 for the Texas Zephyr. Length was 88'8" over coupler faces.
If the distance between truck centers remains constant, but the car is lengthened, then overhang on the inside of a curve will remain constant. The overhang on the outside (the car corners) is already much less than on the inside. So clearances could be maintained if several feet were added to the car ends.
Diaphragm alignment wouldn't be a problem if the longer cars were not mixed with standard length cars. It is also quite possible that there would be minimal problems if they WERE mixed. Were there problems when "standard" length passenger cars were mixed with shorter ones?
My guess at the reason it isn't happening would be that the people who are searching for passenger cars work in government bureaucracies--hardly havens of out-of-the-box thinking (at least, on company time).
You might see something happen if someone in Europe does it. Apparently, if it's done in Europe, that makes it acceptable here.
Ed
The 'logical' place to put truck pivots is at the 'quarter points' of the averagely-loaded car -- geometrically this accounts for the weird-at-first-glance truck placement on the Siemens ACS64. Note, however, that heavyweight cars put the trucks nearly at the ends, even though this mandates much heavier underframe construction. That is so to minimize motion between adjacent car ends as much as to keep wheel noise away from sleeping passengers.
With greater length from truck pivot to end of car, the drawbar arrangement has to swing further, and arrangements for tightlock coupling with very low slack become difficult with longer drawbars. Where the peak concern comes in is not so much curves on the road as negotiating what amount to tight reverse curves in station trackage. So a higher proportion of any 'extra' car length would have to be in the center span ... and that lengthening likely would weaken the car structure out of direct proportion to cantilever dimension, in addition to causing potential gage interference.
`Over hang can be serious when tain goes thru slip switches maybe just changing one parallel track. Have seen only less than 1/3 opening between cars tansiting the same.
But, keep in mind that trailer flats have a huge amount of overhang beyond the trucks. One could ask why they can pull it off, and not passenger cars.
7j43k But, keep in mind that trailer flats have a huge amount of overhang beyond the trucks. One could ask why they can pull it off, and not passenger cars. Ed
CSSHEGEWISCH 7j43k But, keep in mind that trailer flats have a huge amount of overhang beyond the trucks. One could ask why they can pull it off, and not passenger cars. Ed They don't pull it off that well.
Any number of derailments have been caused by the lateral forces that come into play on curves when cars with long overhang are coupled together. I can remember a series of pictures in "Photo Section" in TRAINS in the late 1960's which documented a derailment on Horseshoe Curve caused by lateral forces while it occurred.
Stringlining is a failure due to lateral forces. But it is not especially caused by a large overhang beyond the trucks.
I would be interested in reading more about this derailment on Horseshoe Curve. Who produced the analysis of the cause(s)?
In their minds - everyone thinks about draft forces. Buff forces are even more of a consideration - excessive buff force from the right angle will very easily pop a car off the track. Draft and Buff foces are constantly moving through long trains.
True.
But I don't view passenger trains as long trains.
And they SHOULD have much more sophisticated braking, draft and suspension systems.
Here's one problem with extending the car but keeping the truck centers the same:
At the center of the car, a passenger feels HALF of the displacement of (either) truck movement.
At the truck mounts, a passenger feels ALL of the displacement of (that) truck movement.
As the passenger goes beyond the truck mount, the passenger displacement continues to increase.
Of course, all of the displacing mentioned above is moderated hugely by the suspension.
But it's a thought.
7j43kTrue. But I don't view passenger trains as long trains. And they SHOULD have much more sophisticated braking, draft and suspension systems. Ed
The UP's City of Everywhere was frequently 25 cars or so. In the context of today's freight trains that is not that big, in the context of trains in the pre 1971 era it was humongus for a passenger train. In today's world Auto-Train is the longest and I believe is limited by CSX to 50 cars - at 50 cars the train would consist of 12-16 passenger carrying cars and the balance would be vehicle carriers.
City of San Francisco, leaving Berkeley CA:
5 PA's, 1 PB, 26 cars
Christmas season, 1965
(One of the huddled masses, yearning for turkey and dressing. And gravy.)
In the late 50's, In the December , I used to see the PRR's #13 mail train heading toward St Louis with over 30 cars of mail and express plus one coach. Longest passenger train I rode was the Canadian leaving Toronto. It had 3 P42's baggage, 2 coaches, skyline dome, then 3 sets of 6 sleepers, skyline lounge, diner, followed by a Park dome observation car for a total of twenty nine (29) cars.Total of 1 baggage, 2 coaches, 18 sleepers, three diners, 4 Skyline domes, & the Park jobs dome. Stuck way out of the train shed in Toronto.
CSSHEGEWISCH 7j43k But, keep in mind that trailer flats have a huge amount of overhang beyond the trucks. One could ask why they can pull it off, and not passenger cars. Ed They don't pull it off that well. Any number of derailments have been caused by the lateral forces that come into play on curves when cars with long overhang are coupled together. I can remember a series of pictures in "Photo Section" in TRAINS in the late 1960's which documented a derailment on Horseshoe Curve caused by lateral forces while it occurred.
Derailments of WB trailer flats entering Pitcairn Yard (east of Pittsburgh) in the 70s became so frequent that WB trains with trailer flats had to be crossed over to the EB main before reaching Pitcairn. This avoided a double reverse through two closely spaced crossovers.
ChuckAllen, TX
cefinkjr Derailments of WB trailer flats entering Pitcairn Yard (east of Pittsburgh) in the 70s became so frequent that WB trains with trailer flats had to be crossed over to the EB main before reaching Pitcairn. This avoided a double reverse through two closely spaced crossovers.
I agree that 89' flats can't be run just anywhere. And I see that someone eventually found a work-around (after "frequent" derailments--quick thinking, guys!).
However. 89' flats were, and are, hugely successful. And railroaders were forced to deal with them.
What did NOT happen was railroads dropping 89' flats because of the derailments at Pitcairn Yard. Or at the Horseshoe.
Thus, it has been demonstrated that 89' long cars can be operated on railroads. Railroads had to deal with a new kind of car, and did.
No one has explained why a passenger car could not do what a freight car can do.
89' cars have to have long drawbars with a lot of travel. May be an issue with passenger cars.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
7j43kNo one has explained why a passenger car could not do what a freight car can do. Ed
What would be the economic justification for a longer passenger car?
Economics is what drives railroad - on both the freight and passenger fronts. Note - when additional passenger capacity was required - passenger operators went to double decking 'standard' length cars and not lengthening cars.
The economic justification would be the usual: increased profit.
Sorta like when they lengthened trailer flats to 89'.
zugmann 89' cars have to have long drawbars with a lot of travel.
89' cars have to have long drawbars with a lot of travel.
I suspect they have to have long drawbars to minimize lateral forces, based on their radically inset trucks.
I am assuming "a lot of travel" refers to sideways swing on the drawbar, as opposed to longitudinal travel.
May be an issue with passenger cars.
It may, or it may not. I don't see any particular reason that it would.
7j43kThe economic justification would be the usual: increased profit. Sorta like when they lengthened trailer flats to 89'. Ed
So if a standard passenger car runs $2M and it equates to $10M a car to streach it, and $2.5M to 'stack' the passengers - what is the economic justification to streach it.
Streaching requires new engineering, stacking basically doesn't.
Just a thought-- I'm an outsider, but in reading the last few responses from railroaders, I get the impression that they can handle 89' flats but have to put up with occasional derailments. Maybe freight is a little more tolerant of occasional derailments than passengers would be.
_____________
"A stranger's just a friend you ain't met yet." --- Dave Gardner
BaltACD 7j43k The economic justification would be the usual: increased profit. Sorta like when they lengthened trailer flats to 89'. Ed So if a standard passenger car runs $2M and it equates to $10M a car to streach it, and $2.5M to 'stack' the passengers - what is the economic justification to streach it. Streaching requires new engineering, stacking basically doesn't.
7j43k The economic justification would be the usual: increased profit. Sorta like when they lengthened trailer flats to 89'. Ed
Yes. That is in accordance with what I said.
Paul of Covington Just a thought-- I'm an outsider, but in reading the last few responses from railroaders, I get the impression that they can handle 89' flats but have to put up with occasional derailments.
Just a thought-- I'm an outsider, but in reading the last few responses from railroaders, I get the impression that they can handle 89' flats but have to put up with occasional derailments.
Derailments happen to all kinds of freight cars. And locomotives. And railroads have to put up with them.
When it is believed that the derailments are excessive, then corrective action can be taken (see earlier comment about Pitcairn Yard).
The corrective action of eliminating 89' flats did not happen.
Maybe freight is a little more tolerant of occasional derailments than passengers would be.
I expect that's true.
But, so far, no one has connected the dots:
There were derailments of 89' flats--first dot
89' passenger cars would derail too often to be acceptable--last dot
7j43kThus, it has been demonstrated that 89' long cars can be operated on railroads. Railroads had to deal with a new kind of car, and did. No one has explained why a passenger car could not do what a freight car can do. Ed
You seem to have ignored Balt's comment about narrower width. While an 85' Viewliner II and many other passenger cars are 10' 6" in width, the 89' flatcars are 9' 11.375" in width. They were not made narrower than typical freight stock on a silly whim.
charlie hebdo 7j43k Thus, it has been demonstrated that 89' long cars can be operated on railroads. Railroads had to deal with a new kind of car, and did. No one has explained why a passenger car could not do what a freight car can do. Ed You seem to have ignored Balt's comment about narrower width.
7j43k Thus, it has been demonstrated that 89' long cars can be operated on railroads. Railroads had to deal with a new kind of car, and did. No one has explained why a passenger car could not do what a freight car can do. Ed
You seem to have ignored Balt's comment about narrower width.
Perhaps to you. I did respond to Balt's comment three posts later.
While an 85' Viewliner II and many other passenger cars are 10' 6" in width, the 89' flatcars are 9' 11.375" in width. They were not made narrower than typical freight stock on a silly whim.
And how wide is an auto-rack equipped 89' flat?
https://www.bnsf.com/ship-with-bnsf/ways-of-shipping/equipment/pdf/Tri-Level-Specs.pdf
http://www.bnsf.com/ship-with-bnsf/ways-of-shipping/equipment/pdf/Bi-Level-Specs.pdf
According to this it says "Extreme" Width 10' 8"
Or we can go "Extra Long" 141'
http://www.bnsf.com/ship-with-bnsf/ways-of-shipping/equipment/pdf/AutoMax-Specs.pdf
7j43kPerhaps to you. I did respond to Balt's comment three posts later.
Moving the trucks inward would reduce the overhang at the mid point of the curve. Unfortunately the ends will now swing wider towards the outside of the curve. Both factors are equally critical clearance issues.
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