BaltACD GN had electrics for Cascade until the middle 50's didn't they?
GN had electrics for Cascade until the middle 50's didn't they?
Yes. Tunnel ventilation was improved so diesels could continue thru with out having to change to and back from electrics.
SD60MAC9500This sounds awfully complicated... BNSF seems to get all traffic through today with minimal issue..
The length of time it takes for diesel exaust to clear the tunnel is the limiting capacity factor on the line.
MidlandMike SD60MAC9500 This sounds awfully complicated... BNSF seems to get all traffic through today with minimal issue.. The length of time it takes for diesel exaust to clear the tunnel is the limiting capacity factor on the line.
SD60MAC9500 This sounds awfully complicated... BNSF seems to get all traffic through today with minimal issue..
Any limiting factor in Cascade Tunnel would be its Eastbound grade of 1.57%. BNSF has been able to push through as much as 30+ trains a day through Cascade Tunnel. Westbound trains going through the tunnel actually help clear out exhaust going downgrade.
SD60MAC9500 MidlandMike SD60MAC9500 This sounds awfully complicated... BNSF seems to get all traffic through today with minimal issue.. The length of time it takes for diesel exaust to clear the tunnel is the limiting capacity factor on the line. Any limiting factor in Cascade Tunnel would be its Eastbound grade of 1.57%. BNSF has been able to push through as much as 30+ trains a day through Cascade Tunnel. Westbound trains going through the tunnel actually help clear out exhaust going downgrade.
It takes 20 minutes for a train to get thru the tunnel, but it takes 30 minutes after that to clear the fumes. 50 minutes per train gets you the 30 trains per day. Note that I used the word "capacity" in the limiting factor.
A perhaps hare-brained idea...
Have one or two battery locomotives fitted out with some of fixture (air bladder??) that would have a minimal gap (a few inches?) with the tunnel wallls. After a train clears the tunnel the locomotive(s) with fixture would act as a piston pushing the air out of the tunnel. At 30 mph, it would take about 16 minutes to traverse the tunnel.
Erik_Mag A perhaps hare-brained idea... Have one or two battery locomotives fitted out with some of fixture (air bladder??) that would have a minimal gap (a few inches?) with the tunnel wallls. After a train clears the tunnel the locomotive(s) with fixture would act as a piston pushing the air out of the tunnel. At 30 mph, it would take about 16 minutes to traverse the tunnel.
They could perhaps be operated crewlessly.
The battery loco/piston should be able to clear the tunnel from either direction, so shouldn't need repositioning after traveling through the tunnel. I would be very surprised if pushing the air through the tunnel didn't require a lot of power, but it is well within COTS battery technology. Also why I wrote locomotive(s).
Agian, this was proposed as an "way out of the box" idea.
Erik_MagHave one or two battery locomotives fitted out with some of fixture (air bladder??) that would have a minimal gap (a few inches?) with the tunnel wallls.
Depending on the tunnel wall construction, perhaps a better solution along these lines would be a series of brushes. These would not be affected by irregularities in the tunnel walls (ice, outcrops, etc). Two or three rows on one unit would be almost as functionally air tight as a bladder.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Has anyone actually consulted the Train Dispatchers for the territory to learn and understand their philosophy's in operating the territory that includes the tunnel and its operating constraints?
Never too old to have a happy childhood!
BaltACD Has anyone actually consulted the Train Dispatchers for the territory to learn and understand their philosophy's in operating the territory that includes the tunnel and its operating constraints?
Go here:
https://www.trainorders.com/discussion/read.php?1,2048593,2048720,nodelay=1
Scroll down to the explanation by TAW (Thomas White).
Key quote: "...the presence of a tunnel and the need for ventilation is irrelevant. Running time between Scenic and Berne is the capacity limiting factor."
That's been the take on Cascade Tunnel that I've read and heard from everyone who really knows anything about how things operate there.
Seems like there was an article in one of the RR mags in the not-too-distant past specifically about said tunnel.
Out of curiosity, I know there is barely enough room for anything above a double stack in the tunnel, but is there zero room at all? I was watching a ride along video of the Caltrain highlighting some of the electrification efforts on that line and in at least one of the tunnels, rather than raising it, they are using some form of fixed metal rail along the top as the transmission method. the youtuber (who is an engineer) speculated aluminum. Could such a system which involves much less equipment overhead work in Cascade tunnel? Also, with the new Battery Locomotives under test, would a mixed consist reduce emissions enough to reduce flush time? I'd have to imagine not for an east bound train.
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To me, saying that the siding locations determine capacity, so electrification or other smokeless operation is rediculous, is a stqtment that is rediculous. Ever hear of "fleeting?" And I'm pretty certain BNSF uses or used the concept on the Transcon where single'track sections interrupred a double-and-multiple-track main line. On the Casdcade line, this would involve closely spaces multiple sections of long westbound trains meeting widely-speced siding-fitting single eastbound trains for half a day and then the reverseve for the other half of the day. But fleeting is not possible with the currrent ventillation time requirements.
David, if you're referring to TAW's description of Cascade Tunnel operations, he did not say that the siding locations determine capacity. He (and others) said that the running time between the sidings determines capacity. Those being the sidings at opposite ends of the tunnel, Scenic and Berne,
Running time is a factor of not just the distance between those two sidings, but also the grade and authorized track speed between them. Eastbounds departing Scenic have just climbed a 2 percent compensated grade and are entering a nearly 8-mile long tunnel where the climb continues at 1.57 percent. Westbounds departing Berne are climbing an undulating grade of up to 2.2 percent. The summit is just outside the tunnel's east portal. Maximum authorized speed between Scenic and Berne is 30mph passenger and 25mph freight.
A side note: does pushing all that smoke, carbon monoxide and etc. out the ends of tunnels for years kill all the vegetation at the ends of the tunnel?
Thanks to Chris / CopCarSS for my avatar.
Murphy Siding A side note: does pushing all that smoke, carbon monoxide and etc. out the ends of tunnels for years kill all the vegetation at the ends of the tunnel?
Pictures I have seen of the area do not give the 'moonscape' apperarance that I noticed as a child when our family vacation took us through Sudbury, ON.
No. Trees love the rain that characterizes the wet side of the Cascades and they love carbon dioxide. Happy, happy trees.
Mac
As was implied in the prior post, the east slope of the Cascades is a different story. The landscape around Wenatchee is signicificantly drier and the dominant color is a light brown.
The running-time problem can be solved (not of-course to the extent of a double-track railroad or closer-spaced sidings) by fleeting. Possibly I have not explained the concept well, and possibly someone else can explain it better. Fleeting can probably double existing capacity.
Isn't that similar to PSR and some of the 15k foot trains out there?
Is there a issue for DPUs or closely followed manned units being able to breath?
daveklepper The running-time problem can be solved (not of-coursec to the extent of a double-track railroad or closer-spaced sidings) b y fleeting. Possibly I have not explained the concept well, and possibly someone else can explain it better. Fleeting can probably double existing capacity.
The running-time problem can be solved (not of-coursec to the extent of a double-track railroad or closer-spaced sidings) b y fleeting. Possibly I have not explained the concept well, and possibly someone else can explain it better. Fleeting can probably double existing capacity.
Backshop daveklepper The running-time problem can be solved (not of-coursec to the extent of a double-track railroad or closer-spaced sidings) b y fleeting. Possibly I have not explained the concept well, and possibly someone else can explain it better. Fleeting can probably double existing capacity. Of course, "fleeting" implies that the originating yards can put together a number of outbound trains in a short amount of time.
Of course, "fleeting" implies that the originating yards can put together a number of outbound trains in a short amount of time.
Not really as their can be a intersection of lines that feed traffic into the direction that is being fleeted.
Yards that are constructed to dispatch complete trains - can depart trains from their 'Departure Yard' one right after the other. Yards where trains have to double tracks together cannot do that.
Fleeting through the Cascade tunnel would require a solution to the ventilation problem. Similar issue with very long trains, there will be a point where the trailing DP units do not have an adequate supply of cool clean air.
I would be suprised if the yards originating the bulk of the longer "Northern Transcon" trains cannot put several tgether without doubling. If I'm wong. then those yards need investment in anycase. Branch operation should not be a problem given the right analysis and schedule planning.
Erik_MagFleeting through the Cascade tunnel would require a solution to the ventilation problem. Similar issue with very long trains, there will be a point where the trailing DP units do not have an adequate supply of cool clean air.
I haven't seen this point made explicitly yet, but presumably a zero-carbon hydrogen locomotive with proper variable air compression would suffer comparatively less -- if indeed at all from an engineering standpoint -- from even high-demand operation in tunnels of this kind. The 'crew' issues then become protection from superheated humid air rather than breathing integrity -- and I'd argue that relatively simple changes to S-580 cabs would offer the necessary protection.
In any case, the combination of dual-mode-lite external power plus CBTC would allow any number of fleeted movements to pass through the tunnel at near to full allowable road speed, with minimum physical separation. That eliminates most if not all the practical concerns Mr. Kelly mentioned, although it does impose capacity limits if no effective yarding facilities for the fleeted trains cannot be provided within the operational segment of the railroad that contains the tunnel.
Note that the method that was mentioned as "efficient" -- routing trains alternately in opposing directions, net of all ventilation time required to clear -- is as much of a false 'economy' as the idea that container cranes should 'utilize the return travel' by picking up a container for unloading each time a different container is placed for loading. The idea of optimizing travel time across the fixed bottleneck imposed by physical running speed is valid, but it does not take account of percentage of effective track occupancy over the stretch, provided road speed can be maintained by all trains over it. Obviously effective CBTC alone will greatly increase that if traffic can be blocked directionally by daypart, which it seems to me is a premise of any real scheme of PSR in operations.
Of course the one relatively large question is how the power for electrification gets there. It might be less than expected, though, if the electricity to run a cycle of the ventilation system can be saved.
This thread has seen many fantastigorical solutions to a straight forward problem, which is that BNSF has more traffic that could/should use the former GN Cascade Tunnel, than the tunnel can physically handle. TAW is correct, the issue is running time between Scenic and Berne, and it is what it is. The solutions most of you have proposed all add cost, complication, and delay.
I grew up in Wenatchee, clerked for the GN, rode thru Stevens Pass on passenger trains in freight cabs, rode thru Stampede on my uncle's passenger trains, and am familiar with the rail geography of Washington.
Traffic on the Cascade tunnel line is first and foremost intermodal to and from South Seattle (domestic) Port of Seattle, and Port of Tacoma. Many of these trains are DPU powered. I do not know where the DPUs come on and off, but would bet the vast majority are on/off at Hauser Yard 15 miles or so east of Spokane where every train to and from Vancouver WA and Puget Sound points gets fueled westward and eastward.
The best way to increase capacity is to get the Empire Builder to go away. That has not happened for 50 years and there is no reason to expect Congress to quit pouring money down the ATK rathole, so assume that particular burden will not go away.
The line handles one pair of mixed carload trains between Everett and Spokane/Hauser. All else is intermodal. These trains have long operated in DPU mode, itself increasing capacity for intermodal traffic via Stevens Pass
There are Bulk traffic, grain, coal, and oil unit trains that would/should use the route IFF it had the capacity, which it has not for any years. BN's first response was to route carload and bulk, and even intermodal via Vancouver Washington then to the two main track line between Vancouver WA and Everett. Converting the intermodal trains to DPU seems to have been enough to get them off the long mile, longer time route via Vancouver WA. Today oil and coal trains continue up the single track former GN main line to their destinations north of Everett and south of Vancouver BC.
The bad thing about this route is that it is significantly longer than the Cascade tunnel route, say about 180 miles longer Spokane to Seattle. The good thing is that the ruling grade is significantly less, 1% vs 2.2%, so required horsepower per ton/train is only half what is needed to lift loads over the mountain. The reduction in horsepower hours is less than 50% due to the excess mileage. That excess mileage also generates higher operating costs than would otherwise be the case, but when the capital investment solution is very expensive, you live with higher than ideal operting costs.
The BNSF reopened Stampede Pass in the 1990's as a relief route for carload traffic. Stampede has had restricted clearance since the largest Z class steam engines came along in the late 1920s or so. BNSF chose not to clear the tunnel before restoring it to service, the best time to have done that work. Stampede is shorter than the route via Vancouver AND puts the carload traffic thru the former NP hump yard at Pasco. My very soft guess is that this amounts to one train a day to/from Everett, Seattle, Tacoma each. This too is a mountain route with 2.2% grades both ways between Easton and Lester.
A few years ago the BNSF and the operating crafts entered into an agreement for a three legged crew district; Pasco to Vancouver WA, Vancouver to Seattle, and Seattle to Pasco. Each crew works those segments in that order. The target traffic is the unit trains, and for them Pasco to Vancouver, and Seattle to Pasco is functionally a paired track. The objective was/is to reduce the number of meets on the Columbia Gorge line. Since eastward bulk trains are empty the power that brought them west can get them over Stampede.
This is practical railroading and avoids the high capital cost of engineering solutions. Is it perfect? No, but is much better than the alternative.
There has been discussion of the former MILW Snoquamie Pass line. It is a reasonable alternative between Easton and Renton. The problem is that while this middle is OK, the ends are not. On the West end, the line features street running for about a mile through downtown Renton. Considering how Auburn pitched a fit when BN reopened Stampede Pass, which had no physical impact on anyone or any thing, imagine how Renton would explode at the idea of running real trains through downtown. The track is intact and BNSF uses it to deliver airplane parts to Boeing's Renton plant. Two moves of 1-6 cars per trip.
The MILW east of Easton presents two unattactive features. First assume that the target traffic is intermodal. Carload needs to go to Pasco, and quicker time for intermodal is always a good thing. The map gazers look at old maps and say 'What a great short cut the MILW would make between Ellensburg and Lind' and 'The MILW was the shortest fastest line'.
What they do not see is Eastern Washington State University in Ellensburg which has grown up around, if not on, the MILW right of way. That is fixable with lots of money. Not reasonably fixable is the relatively short 1.6% eastward ascending grade and the 20+ mile 2.2% ascending grade westward from the Columbia River. This right of way is owned by the State of Washington. Can you really see them plowing through their own University? Finally, Stampede is not cleared fof double stack, so your intended traffic can not use the route.
I give you all lots of points for imigination, but not much for practicallity.
Mac McCulloch
PNWRMNMI give you all lots of points for imigination, but not much for practicallity.
Hey, you never know.
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