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Double stack verses conventional COFC...

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Posted by greyhounds on Tuesday, August 11, 2009 10:37 AM

Paul_D_North_Jr

greyhounds - OK,  thanks for the example.  I wasn't so much thinking of 'getting rid of' either one or any of them, but in the context of a marketing and costing approach - where some could clearly best go via 1 method, but others are pretty much indifferent and 'up for grabs' - asking the more general question of, "How do we sort out which of the 'tools' to use for each segment of the market ?"  Sure, I know, 'lowest cost and most efficient' for each - but what if the economics get much better for 1 method by not using another one, at the present or projected levels and sources of traffic ?

A couple of further and different thoughts:

Rail lines that are mostly unoccupied and not used at maximum capacity with frequent trains are a potentially lost 'opportunity cost' - just the same as the single-level COFC train in my example above that doesn't use near all of the weight capacity of the cars or track structure, or space capacity of the clearance diagram. 

Most days I take my lunch and eat up by the double-track NS Reading Line in the hopes of seeing a train - and most days I could sit between the tracks and not be disturbed by anything on either track during that 30 or 45 minutes, or if something does comes by, it's usually just the local switcher.  To be fair - and to illustrate the point - other days there are as many as 3 trains that go by, sometimes in the same direction on as close as 10-minute headways/ spacing. 

When I drive west during the day on essentially parallel I-78 from Allentown to Harrisburg, to relieve the boredom I count the tractor-trailers = potential loads going east in 10-minute increments - it's usually in the 120 to 130 range.  Why aren't more of them on the rails ?

Others here have said that the railroads have optimized their revenue/ profit yield with the present mix of intermodal and regular trains for the line capacity, differential pricing, and so on.  But I don't believe it.  We have yet to see a railroad seriously try - in a contemporary, post-2000 market - a 'SouthWest Airlines on rails' approach of proposing to run many intermodal trains and slots to fill a line to capacity - say, hourly, even;, low, competitive but compensatory rates; and marketing for traffic to fill those slots.  Yes, terminal capacity is a constraint, and its a big gamble, and so on.  But some methods have lower terminal costs, and all of the equipment can be used elsewhere if it doesn't work out.  Besides, a lot of that equipment is sitting idle right now anyway . . . Whistling

Just some food to provoke further thoughts.

- Paul North.

That's a good point. 

We were talking about the Tyson mega beef plant at Dakota City, NE (across the Missouri River from Sioux City).   That huge plant is at the end of the CN's Iowa line.  This line has little businesss, only a very few trains per day. 

All along that line in western Iowa from Sioux City and Council Bluffs are meat plants (slaughter and processing facilities.)  Tyson alone has facilities in Cherokee, Council Bluffs. Denison, Storm Lake and Waterloo, Iowa.  The Waterloo facility kills over 19,000 hogs per day.  Four states produce 50% of the red meat in the US.  Iowa and Nebraska are two of them.  The people in Iowa and Nebraska aren't eating all this beef and pork.

Much of this freight is moving over 1,000 miles to northeast consumers.  Now, if the CN can't be truck competitive at 1,000 miles, they can't be truck compettiive at all.  It just seems to me that they've made the decision that they'd rather have a greatly underutilized line through Iowa than to develop this business.

Does anyone have any idea why they would make such a decision?  Maybe there is a good reason.  If there is, I'd sure like to understand it.

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by Paul_D_North_Jr on Tuesday, August 11, 2009 9:48 AM

Original Post -

Ulrich
Intuitively doublestack makes alot of sense... by stacking containers you shorten the train and you improve the loaded verses tare weight ratio. But when I look at a double stack train I see alot of empty space between well cars... so each set of stack containers catches the wind and the space savings gained in stacking containers appears to be negated to some extent by the huge gaps between well cars. Compare to a standard COFC...you've got what looks like an unbroken string of containers with a relatively low center of gravity. So one has to wonder...taking into account the specialized equipment for doublestack... the greater clearances... the specialized equipment and facilities needed to on and off load...just how much more efficient is double stack over COFC?
Ulrich, since you're from Canada, I meant to ask this before

 What's the 'word' or consensus on CPR's ''Expressway'' [formerly ''Iron Highway''] operation, which now has a network from Montreal [1 terminal] to and through Toronto [2 terminals - Milton and Agincourt], to Detroit [1 terminal] / or Windsor [1 terminal] ?  For the CPR website for it, see

http://www8.cpr.ca/cms/English/Customers/New+Customers/What+We+Ship/Expressway/default.htm 

In particular, see the seemingly unimportant-looking links in the right-hand margin for 'How to Ship', 'Schedule', 'Facilities', and 'Network Map', each of which open into separate 'pop-up' windows.

[Note: It has been amazingly hard for me to access any other detailed or reliable technical and economic information about it.]  So:

Is it commercially successful

Who uses it

Would or do you ?

Why or why not ?

Strengths and weaknesses of it, from your standpoint ?

Any other comments you care to add ?

It would seem to me to have many of the advantages of the COFC operation that you initially asked about, with fewer of the disadvantages.

Looking forward to your response.

- Paul North.
"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by Paul_D_North_Jr on Tuesday, August 11, 2009 9:15 AM

The comment above from passengerfan/ Al-in-Stockton reminded me of another comment that I meant to post earlier, as follows

A COFC-only opportunity that I think both Amtrak and NS are missing is to run a couple of daily trains thru the Amtrak tunnels under the Hudson/ North River, thru/ past Penn Station, and under the East River to an new low-budget intermodal terminal on Long Island, which is a grievously underserved rail and intermodal market.  Plus, from there a short dray back-haul would get into Manhattan and the other NYC boroughs on that east side of the Hudson.  These are all potentially huge and basically truck-only now - the present rail route can't be truck-competitive on the scheduling/ running times.  Aside from the car-float, it's to Albany, then either down Metro-North on the east side of the Hudson, or over to and through Connecticut back down by some devious route.

Instead, to first be able to get through the tunnels, I'd propose compiling or blocking the train, including 'filleting' [= unloading the 2nd level of double-stacks as needed to make it into a single-level COFC train] NYC-bound double-stacks and other containers as needed at a close-in terminal, such as the LVRM Beth-Intermodal terminal in Bethlehem, PA.  Either there, or maybe doing that and/ or running a dedicated COFC train from further out west - like Harrisburg or Chicago.

Then move under conventional diesel power aross North Jersey to arrive at the Hudson River tunnels in the early evening - after the outbound commuter rush in the opposite direction is mostly done, but before the M-O-W people need to claim the tunnels for their activities during the overnight low-traffic/ shutdown hours.  Attach an Amtrak E-60 electric or two - if there are any still in service - to tow the idling diesels thru the tunnels and Penn Station to the vicinity of Sunnyside Yard, at about 30 MPH max. to minimize track wear and damage, from whence the diesels can move under their own power again to the new IM terminal for unloading before midnight.  That way the boxes can hit the street in the early morning hours, and be drayed and delivered both into the City and onto the Island before the start of the next business day.  The outbound empty move can happen in reverse just before or after the morning commuter rush going the other way.

As to the economics - considering the tolls, truck driver and route limitations, and traffic congestion, etc., it seems to me that just the river crossings via the tunnels and the cross-town move ought to be worth around $100 per box to the trucking co.'s or shippers [plus an appropriate per-mile rate for the 50 or so miles across North Jersey and a couple miles out onto Long Island].  If that value holds up, then each train of 100 cars = 100 boxes ought to earn around $10,000 for that segment of the run, to be shared between NS and Amtrak - say, 50-50, or $5,000 each per train.  So for a little bit of track maintenance cost and some scheduling effort to utilize otherwise unclaimed train slots, Amtrak could earn $30,000 a week (say, only 6 nights a week) or about $1.5 million per year, per train slot.  That's not going to solve the perpetual Amtrak budget shortfall by itself, but it's not trivial, and will also make some friends in NYC political circles for reducing truck traffic and vehicle congestion, etc.  Plus, if the carbon credits are worth anything, that would contribute to the 'value-added' that could be available and claimed by one of the participants.

Any thoughts on this ?

- Paul North.

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by greyhounds on Tuesday, August 11, 2009 9:13 AM

Dakguy201

Minor quibble -- Dakota Dunes SD is a very upscale residential community whose only "industrial" activity is medical clinics escaping the Iowa income tax, which can be very significant for high income individuals.   It is the corporate headquarters of the company formerly known as IBP, now a division of Tyson Foods, as a former IBP CEO sought a low tax enviroment for himself and his executives.   

In one of their last acts of arbitrary regulatory insanity, the ICC ruled that a TOFC train of meat departing from a nearby Nebraska IBP plant represented unfair competition and ordered it discontinued.  The freight went back to trucks, where it remains to this day.

Thank you.  I switched Dakota Dunes, SD and Dakota City, NE in my listing.  I'm glad you caught it.

The communities are about 13 highway miles apart.  As you say, the offices are in Dakota Dunes.  The mega beef plant is in Dakota City.

 

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by Los Angeles Rams Guy on Tuesday, August 11, 2009 6:38 AM

greyhounds

Paul_D_North_Jr

 

Although let me ask this, as a 'devil's advocate' - Would you be able to justify not running a more-efficient and economical double-stack operation, so as to provide more volume to one of the otherwise lesser-used intermodal methods, so as to reduce its unit costs ?  In other words, how do we evaluate and decide which of our intermodal 'children' do we sacrifice to save the others ?  Tonight, that seems like a pretty challenging intellectual and economic question to me.  Your thoughts

- Paul North.

No.  And I don't think I'd ever even try to justify such a thing.  You're looking at this as an "either or" proposition, and it's not.  There would be no reason to get rid of a double stack operation to support a RoadRailer (or other) operation.  The idea is to just hook the RoadRailers (or preferably RailMate) on the back of the DS train and operate an integrated intermodal system using each technology to the best of its advantage.

I'll use an example to illustrate.

BEEF!

In 2008 the US produced 26.7 BILLION pounds of beef.  That would be about 636,000 loads @42,000 pounds each.  The beef production is very concentrated.  Just 14 plants produce 55% of this beef.  Plant locations are concentrated.  Five of the 14 are in the Texas Panhandle.  Four are in southwest Kansas.  Two are in Colorado north of Denver.  One is in Grand Island, NE. One is in Dakota Dunes, SD and one is actually east of the Mississippi River in Geneseo, IL.  (It's just east of the river.)

The beef moves long distances by over the road trucking.  The railroads catch an ocassional reefer car of export frozen beef.  But for the most part this high volume, long haul freight is on the Insterstate System.  In 25 years double stack has not made a dent in this business.

Why?  There aren't any double stack terminals anywhere near the production areas, that's why.  Let's take the four plants in SW Kansas.  (Two at Dodge City, one at Holcum, and one at Liberal.)  They each pump out around 500 loads per week.  This beef goes a long way.  It goes to population centers on both coasts, in the midwest, and in the south.  It doesn't go by rail.

To make intermodal competitive for this business there needs to be at least one intermodal terminal in SW Kansas.  Could it be a double stack terminal?   I doubt it.  Although there are, on average, 400 loads per workday available, the railroad can't expect to get every load.  And the loads it does get will be going to many diverse destinations.  The train will have to be "worked" at some point which would mean unloading the containers and reloading them or "horors", switching the cars.  In any event, the high investment required for a DS terminal would sink an operation with this volume.  The "chassis match" problem would also be difficult.

Now consisder putting a RoadRailer/RailMate terminal in SW Kansas.  Capital investment would be negligible for such a terminal.  Run the bi-modal train into Kansas City and sort 'em out using the yard tractors in the existing IM terminal. Put the RoadRailers/RailMates on the back of existing IM trains east from KC.  If the volume ever grew to the point where it did justify double stack operation just redeploy the bi-modal equipment and begin double stack operations.

The concept is to expand the market available to rail by using each technoligy to its best advantage, not to cannibalize one service for another.

 

Greyhounds - thanks for the Railmate reference.  I hope this equipment does get a shot at this type of traffic.  Only wish it had been around some decades ago when the IC was losing the meat traffic on the Iowa Division.

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Posted by Paul_D_North_Jr on Tuesday, August 11, 2009 5:24 AM

greyhounds - OK,  thanks for the example.  I wasn't so much thinking of 'getting rid of' either one or any of them, but in the context of a marketing and costing approach - where some could clearly best go via 1 method, but others are pretty much indifferent and 'up for grabs' - asking the more general question of, "How do we sort out which of the 'tools' to use for each segment of the market ?"  Sure, I know, 'lowest cost and most efficient' for each - but what if the economics get much better for 1 method by not using another one, at the present or projected levels and sources of traffic ?

A couple of further and different thoughts:

Rail lines that are mostly unoccupied and not used at maximum capacity with frequent trains are a potentially lost 'opportunity cost' - just the same as the single-level COFC train in my example above that doesn't use near all of the weight capacity of the cars or track structure, or space capacity of the clearance diagram. 

Most days I take my lunch and eat up by the double-track NS Reading Line in the hopes of seeing a train - and most days I could sit between the tracks and not be disturbed by anything on either track during that 30 or 45 minutes, or if something does comes by, it's usually just the local switcher.  To be fair - and to illustrate the point - other days there are as many as 3 trains that go by, sometimes in the same direction on as close as 10-minute headways/ spacing. 

When I drive west during the day on essentially parallel I-78 from Allentown to Harrisburg, to relieve the boredom I count the tractor-trailers = potential loads going east in 10-minute increments - it's usually in the 120 to 130 range.  Why aren't more of them on the rails ?

Others here have said that the railroads have optimized their revenue/ profit yield with the present mix of intermodal and regular trains for the line capacity, differential pricing, and so on.  But I don't believe it.  We have yet to see a railroad seriously try - in a contemporary, post-2000 market - a 'SouthWest Airlines on rails' approach of proposing to run many intermodal trains and slots to fill a line to capacity - say, hourly, even;, low, competitive but compensatory rates; and marketing for traffic to fill those slots.  Yes, terminal capacity is a constraint, and its a big gamble, and so on.  But some methods have lower terminal costs, and all of the equipment can be used elsewhere if it doesn't work out.  Besides, a lot of that equipment is sitting idle right now anyway . . . Whistling

Just some food to provoke further thoughts.

- Paul North.

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by passengerfan on Tuesday, August 11, 2009 5:13 AM

From the beginning I looked at Californias HSR system as a means to move priority freight either in Containers or as trailers. My idea since the system would be totally independant of the freight lines why remain at 4'8" why not sixteen foot rail width. In that way the HSR could carry two wide containers or trailers on a lower level and passengers and packages on the upper level. I originally thought of the Boeing 727 QC madel that operated as passenger planes during the day, at the end of the day the passenger interiors were rolled out and freight was hauled all night. The next morning the passenger interiors were once again rolled in and the plane was ready for passengers. With passengers and package express on the upper level this would certainly maximize the use of the trains. I also felt it would be great to extend the HSR corridor north from Sacramento to Redding in order to take traffic off I-5 coming from Washington and Oregon. In this way there would be no need to widen I-5. Trucks and containers would be whisked to LA and San Diego or the Bay area in less than a day. A truck coming from Washington could be delivering in those places the same day it arrives in Redding something impossible to do today. My original idea was also to make the system with Mag-Lev so 300 mph speeds could be attained. It is time to begin thinking outside the box. and we in California have a unique opportunity to show the world what good old yankee enginnuity can  come up with.

Al - in - Stockton  

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Posted by Dakguy201 on Tuesday, August 11, 2009 3:18 AM

greyhounds

In 2008 the US produced 26.7 BILLION pounds of beef.  That would be about 636,000 loads @42,000 pounds each.  The beef production is very concentrated.  Just 14 plants produce 55% of this beef.  Plant locations are concentrated.  Five of the 14 are in the Texas Panhandle.  Four are in southwest Kansas.  Two are in Colorado north of Denver.  One is in Grand Island, NE. One is in Dakota Dunes, SD and one is actually east of the Mississippi River in Geneseo, IL.  (It's just east of the river.)

Minor quibble -- Dakota Dunes SD is a very upscale residential community whose only "industrial" activity is medical clinics escaping the Iowa income tax, which can be very significant for high income individuals.   It is the corporate headquarters of the company formerly known as IBP, now a division of Tyson Foods, as a former IBP CEO sought a low tax enviroment for himself and his executives.   

In one of their last acts of arbitrary regulatory insanity, the ICC ruled that a TOFC train of meat departing from a nearby Nebraska IBP plant represented unfair competition and ordered it discontinued.  The freight went back to trucks, where it remains to this day.

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Posted by greyhounds on Monday, August 10, 2009 9:07 PM

Paul_D_North_Jr

 

Although let me ask this, as a 'devil's advocate' - Would you be able to justify not running a more-efficient and economical double-stack operation, so as to provide more volume to one of the otherwise lesser-used intermodal methods, so as to reduce its unit costs ?  In other words, how do we evaluate and decide which of our intermodal 'children' do we sacrifice to save the others ?  Tonight, that seems like a pretty challenging intellectual and economic question to me.  Your thoughts

- Paul North.

No.  And I don't think I'd ever even try to justify such a thing.  You're looking at this as an "either or" proposition, and it's not.  There would be no reason to get rid of a double stack operation to support a RoadRailer (or other) operation.  The idea is to just hook the RoadRailers (or preferably RailMate) on the back of the DS train and operate an integrated intermodal system using each technology to the best of its advantage.

I'll use an example to illustrate.

BEEF!

In 2008 the US produced 26.7 BILLION pounds of beef.  That would be about 636,000 loads @42,000 pounds each.  The beef production is very concentrated.  Just 14 plants produce 55% of this beef.  Plant locations are concentrated.  Five of the 14 are in the Texas Panhandle.  Four are in southwest Kansas.  Two are in Colorado north of Denver.  One is in Grand Island, NE. One is in Dakota Dunes, SD and one is actually east of the Mississippi River in Geneseo, IL.  (It's just east of the river.)

The beef moves long distances by over the road trucking.  The railroads catch an ocassional reefer car of export frozen beef.  But for the most part this high volume, long haul freight is on the Insterstate System.  In 25 years double stack has not made a dent in this business.

Why?  There aren't any double stack terminals anywhere near the production areas, that's why.  Let's take the four plants in SW Kansas.  (Two at Dodge City, one at Holcum, and one at Liberal.)  They each pump out around 500 loads per week.  This beef goes a long way.  It goes to population centers on both coasts, in the midwest, and in the south.  It doesn't go by rail.

To make intermodal competitive for this business there needs to be at least one intermodal terminal in SW Kansas.  Could it be a double stack terminal?   I doubt it.  Although there are, on average, 400 loads per workday available, the railroad can't expect to get every load.  And the loads it does get will be going to many diverse destinations.  The train will have to be "worked" at some point which would mean unloading the containers and reloading them or "horors", switching the cars.  In any event, the high investment required for a DS terminal would sink an operation with this volume.  The "chassis match" problem would also be difficult.

Now consisder putting a RoadRailer/RailMate terminal in SW Kansas.  Capital investment would be negligible for such a terminal.  Run the bi-modal train into Kansas City and sort 'em out using the yard tractors in the existing IM terminal. Put the RoadRailers/RailMates on the back of existing IM trains east from KC.  If the volume ever grew to the point where it did justify double stack operation just redeploy the bi-modal equipment and begin double stack operations.

The concept is to expand the market available to rail by using each technoligy to its best advantage, not to cannibalize one service for another.

 

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by TH&B on Monday, August 10, 2009 7:45 PM

Good question .

 

Double stacks are great but do seem over rated.   The big gap between double stack cars might not present a big enough wind drag now, but if speeds were to increase it would matter.  So for "slow" trains double stacks is good.  

 

Also the cost of height clearance must matter, this cost might be low in the west but it is more costly to to gain the tall clearnces in the east on older railroads. I've observed a "double stack" train get rerouted with considerable delay to get under an overpass, and in reality there was only one car loaded as a double stacker.  This must cost alot when trains are delayed many hours for this kind of reason.  Especialy when the whole idea of double stacking is to be efficient. I can only see double stacking efficient as long as the height clearances of the railroads are easy to obtain and the train speeds are relatively low. But it seems to have just turned into a convention now since it has proved itself under certain conditions.

 

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Posted by Ulrich on Monday, August 10, 2009 6:41 PM

No sacrifice needed...I see a good mix of double stack, traditional COFC, TOFC, and roadrailer. Double stack seems to dominate...and that would make sense as most container traffic originates and terminates at large terminals. To ask which of these options is best is kind of like asking which tool is better..a hammar or a saw..it really depends on the job at hand.

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Posted by Paul_D_North_Jr on Monday, August 10, 2009 5:51 PM

OK - understood.  You're quite right, I concede that I'm looking the narrow view of the rail operations only, mainly because that's how I understood the question that was posed. 

In contrast, yes, I can see that you're looking at the broader system-wide view, where the drayage costs become significant, for the reasons that you state.  If we take this as a question of ''Which arrangement is the better [or optimum] intermodal system - COFC, double-stack, others such as RoadRailer, Iron Highway, etc., or some combnation of them ?'', then everything else you've mentioned also becomes very relevant. 

If that's where we're going with this, then I need to see if I have anything to add, because I think you've laid out the groundwork and dilemma pretty well, and there's no fundamental difference between us. 

Although let me ask this, as a 'devil's advocate' - Would you be able to justify not running a more-efficient and economical double-stack operation, so as to provide more volume to one of the otherwise lesser-used intermodal methods, so as to reduce its unit costs ?  In other words, how do we evaluate and decide which of our intermodal 'children' do we sacrifice to save the others ?  Tonight, that seems like a pretty challenging intellectual and economic question to me.  Your thoughts

- Paul North.
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Posted by greyhounds on Monday, August 10, 2009 5:00 PM

Paul_D_North_Jr

greyhounds, thanks for pulling out that data. Thumbs Up

For a container, double-stack at 31 cents per mile is 27 % less expensive and so it seems pretty compelling as against COFC at 40 cents per mile, which is $90 per box per 1,000 miles = $200 or so for LA-Chicago, $280 or so LA- NYC [again, all figures are 1992, hypothetical, and ''YMMV''].

greyhounds' point about drayage costs is true and well-taken - but beside the point for this question [even though I agree and also think that's a topic for further discussion].  In this context, those drayage costs are for the portion of the move outside of the terminal gates, and as such would apply equally well [or badly] to all containers at a particular terminal, regardless of whether they are moved to or from the terminal by either double-stack or COFC [unless there's some 'off-the-wall' condition like a so-far-unstated clearance or weight restriction that would preclude the double-stack train from getting to that terminal and so make the dray haul much longer, etc.].

Paul North.

Like Balzes it's "Beside the Point".

Double stacks tend to force rail intermodal traffic into large trains operating between a very few large terminals.  In some places, this is just great.  Wonderful.  Fantastic.  Couldn't ask for anything more.

In other cases, this drives up drayage cost to the point that the line haul efficiencies of double stack are negated by those dray costs and the intermodal system becomes non-competitive with over the road trucking.  It is not feasible to put DS terminals at smaller locations.  There is too much investment required.  And the chassis/container match problem will get out of hand.

Double stacks do minimize rail line haul costs, but they often do so by increasing other intermodal system costs.  The goal is to optimize the overall system efficiency, not just sub-optimize the rail line haul. 

Your contention that it's all equal outside the terminal holds true only if you keep the terminal structure as it is.   A system that allowed more IM terminals would allow substitution of $0.43 rail miles for $0.75 truck miles.  (1992 figures again)   You seem caught up in maximizing the rail line haul efficiency at the expense of everthing else. 

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by Paul_D_North_Jr on Monday, August 10, 2009 1:44 PM

greyhounds, thanks for pulling out that data. Thumbs Up

For a container, double-stack at 31 cents per mile is 27 % less expensive and so it seems pretty compelling as against COFC at 40 cents per mile, which is $90 per box per 1,000 miles = $200 or so for LA-Chicago, $280 or so LA- NYC [again, all figures are 1992, hypothetical, and ''YMMV''].

greyhounds' point about drayage costs is true and well-taken - but beside the point for this question [even though I agree and also think that's a topic for further discussion].  In this context, those drayage costs are for the portion of the move outside of the terminal gates, and as such would apply equally well [or badly] to all containers at a particular terminal, regardless of whether they are moved to or from the terminal by either double-stack or COFC [unless there's some 'off-the-wall' condition like a so-far-unstated clearance or weight restriction that would preclude the double-stack train from getting to that terminal and so make the dray haul much longer, etc.].

cx500 - wind resistance / air turbulence has been investigated - the topic is not at all 'politically incorrect' - and I believe it was addressed as part of a thread here like 6 to 8 months ago.  I don't recall the conclusions with any degree of confidence, other than maybe it can be a really large figure and have a big effect for high speeds on flat territory, big gaps, and strong 'quartering winds', etc., and not much for trains of closely spaced containers slogging up steep grades with a tailwind - in other words, 'it depends'.  Just playing a little with Al Krug's 'Train Forces Calculator by AAK' at - http://www.alkrug.vcn.com/rrfacts/RRForcesCalc.html - here's what I input and got out:  

Loco Hp = 13,200 [3 ea. 4,400 HP units]

Loco Tons = 630 [3 ea. at 210 tons = 420,000 lbs. = 70,000 lbs. per axle]

Loco Eff% = 85

 

Car Count = 100 [at 55 ft. per 'platform' = 5,500 ft. plus 3 locos = 5,700 ft.

+/-].

 

Car Face Area = 110 Sq. Ft. [10.0 ft. wide x 3.7 ft. high for flat car = 37 Sq. Ft., plus 8.0 ft. wide x  8.0 ft. high = 64 Sq. Ft. = 101 Sq. Ft. for COFC; for double-stack, car = 37 Sq. Ft., plus 8.0 ft. wide x 16.5 ft. high = 132 Sq. Ft. = 169 Sq. Ft. for double-stack] Axles per Car = 2.4 [6 trucks = 12 axles for 5 platforms = 2.4 per platform]  Train Tons = 4,000 for COFC [25 tons per box plus 15 tons tare = 40 tons x 100 cars]; 7,000 for double-stack [25 tons per box plus 20 tons tare = 70 tons x 100 platforms]; also, a double-stack at 4,000 tons to eliminate/ take out/ neutralize that variation as an effect on the results. Grade% = 0.0 [to get rid of that and the train weight as significant factors] Curve Degrees = 0.0 [again, to eliminate that as a significant factor] Here are the results COFC       Speed = 73.7 mph
Rolling drag = 57036 lbs

  Grade drag = 0 lbs
  Curve drag = 0 lbs
  Total drag = 57036 lbs
  Rolling Hp = 11218 hp
    Grade Hp = 0 hp
    Curve Hp = 0 hp
    Total Hp = 11218 hp
 Double-stack - 7,000 tons       Speed = 60.3 mph
Rolling drag = 69710 lbs
  Grade drag = 0 lbs
  Curve drag = 0 lbs
  Total drag = 69710 lbs
  Rolling Hp = 11218 hp
    Grade Hp = 0 hp
    Curve Hp = 0 hp
    Total Hp = 11218 hp
 Double-stack - 4,000 tonsSpeed = 65.4 mph
Rolling drag = 64309 lbs
  Grade drag = 0 lbs
  Curve drag = 0 lbs
  Total drag = 64309 lbs
  Rolling Hp = 11220 hp
    Grade Hp = 0 hp
    Curve Hp = 0 hp
    Total Hp = 11220 hp
 Note that for the same train weight of 4,000 tons, for a change in Car Face Area by 68 Sq. Ft. or 67.33 % from COFC at 101 Sq. Ft. to double-stack at 169 Sq. Ft., the Rolling drag increases by 7,273 lbs. or 12.75 % [from 57,036 lbs. to 64,309 lbs.], and the Speed drops by 8.3 MPH [from 73.7 MPH to 65.4 MPH]. In contrast, adding 3,000 tons to the same train for a revised double-stack train weight adds only 5,401 lbs. of Rolling drag [64,309 lbs. to 69,710 lbs.], and the Speed drops by another 5.1 MPH [from 65.4 MPH to 60.3 MPH].  So, the double-stack configuration - by itself - appears to add as much air resistance as almost doubling the train weight would - on a level, straight track [emphasis added- PDN]  For another comparison, here are the figures for the same 4,000 ton COFC train, but now on a 1.00 per cent grade COFC +1.00 % GradeSpeed = 35.1 mph
Rolling drag = 27021 lbs

  Grade drag = 92600 lbs
  Curve drag = 0 lbs
  Total drag = 119621 lbs
  Rolling Hp = 2534 hp
    Grade Hp = 8684 hp
    Curve Hp = 0 hp
    Total Hp = 11218 hp
 Note that the  +1.00 % grade added 92,600 lbs. of 'grade drag', or more than 12 times as much as the increase in 'rolling drag' by going to double-stacks - and cut the speed by a little more than half. Conclusion:  The added air resistance from double-stacks is not a 'freebie' - but it's not a show-stopper', either, especially when compared to other sources of resistance to train motion.  - Paul North.
"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by cx500 on Monday, August 10, 2009 12:33 PM

Doublestacks forced a major change in how containers were handled.  All too often the container was actually on a highway chassis riding piggyback (TOFC).  With doublestacking, the unnecessary trailer was finally left behind. Canada was ahead of the US in this regard, with containers placed directly on (single level) flatcars as normal practice from the early days of the container revolution.

I am sure the large gaps between containers must create extra turbulence and wind resistance, but quite possibly that is an issue that is not "politically correct" to investigate.  But a double-stacked train is still shorter for the same number of containers, an important consideration on single track where siding lengths can be a constraint.

John

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Posted by greyhounds on Monday, August 10, 2009 11:42 AM

Well, I'm looking at page 173 of "Piggyback and Containers" right now.  On that page DeBoer calculates the terminal to terminal cost of a 6,000 ft train operating 1,000 miles.  He includes only three cost elements: 1) fuel, 2) car capital and maintenance, 3) Box (trailer or cotnainer) capital.  His per box calculated costs are:

TOFC (conventional flatcar) $413

COFC (conventioal flatcar) $401

TOFC (spine car) $413

COFC (spine car) $400

Double Stack $312

RoadRailer $430

The book is from 1992 and so are these numbers.  DeBoer estimated over the road trucking costs in that time frame to be $0.75/mile or $750 for that 1,000 mile run.

The figures are misleading.  As DeBoer notes " All rail costs are route specific and may vary greatly."

Most importantly, the comparision leaves out a very large cost element, the drayage.  At the calculated $0.31/mile it would appear that DS would defeat truck rates right and left.  But that advantage quickly goes away when the complete cost of the intermodal move is consisdered.  Drayage expenses are what limits intermodal competitiveness with trucking and DS exaserbates the problem.

Additionally his calculated double stack economics are dependant on getting that 6,000 foot long train.  That's possible on a very few long haul, high volume routes such as Chicago-Los Angeles.  It's much harder to do on other routes such as Chicago-Dallas, Chicago-Memphis, etc.

Double stack works very well in its niche.  But it's not the Alpha and Omega of intermodal transportation.  As long as the railroads were "full" and could simply load 6,000+ foot stack trains to the capacity of their networks they had no incentive to do anything else.  Now, they might have to get a little more inovative.

RoadRailers (or similar technologies) can attack the drayage problem.  But only if they can mix in the same consists with other rail equipment. We'll see if the railroads finally figure out how to use them.

 

"By many measures, the U.S. freight rail system is the safest, most efficient and cost effective in the world." - Federal Railroad Administration, October, 2009. I'm just your average, everyday, uncivilized howling "anti-government" critic of mass government expenditures for "High Speed Rail" in the US. And I'm gosh darn proud of that.
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Posted by Paul_D_North_Jr on Monday, August 10, 2009 11:02 AM

Despite all the problems that you adeptly mention, I believe that double-stack is still quite a bit more efficient than COFC (= ''Container-On- FlatCar'', single-level) for the following reasons:

COFC also needs specialized equipment, so it has no huge advantage there - either a 'skeleton' car for maximum tare weight advantage, or a TTX-type flat with the box connectors, or something in between - as well as for loading/ unloading.

Instead, I suspect that the real devil in what you're observing is the evolution and variation in container sizes - esp. lengths - in the existing fleet and certain markets - 20 ft., 40 ft., 48 ft., and 53 ft., plus possibly 28 ft. and 45 ft.  That length variation would also afflict a COFC operation and leave a lot of spaces there, too.

The more favorable aspects of double-stack operations are that they use the available carrying capacity of the railroad system more efficiently in the following 2 ways:

1.  The cars, trucks, and track structure are loaded more to their full weight-carrying capacity than a COFC operation would be.  The precise numbers elude me at the moment, but even a full-length street-legal container at 45,000 lbs. payload - maybe 55,000 lbs. gross  = 27.5 tons - will barely compress the springs on a 2-truck railcar; or, a pair of 20-ft. boxes at the same full load would be 110,000 lbs. = 55 tons.  Nor - if several such containers are carried on a 'car' / 'platforms' with an articulated shared-truck arrangement - will it challenge the capacity of the single truck to which it is effectively assigned.  Even allowing 15 tons for the tare weight of the car/ platform, the total load on the truck would then be 42.5 tons to 70 tons = 85,000 lbs. to 140,000 lbs., which is still within the capacity of even trucks for 110-ton payload cars [286,000 lbs. gross].  In contrast, a double-stack car/ platform carrying 2 such containers = 110,000 lbs. / 55 tons - or even more, if the 20-ft. boxes are involved - usually needs 100-ton car trucks at the ends and 125-ton trucks [315,000 lb.] in the middle.  Although those loads are rarely approached, they do make more effective use of the available capacity of the trucks and track structure.

2. Track capacity and train length limitations and constraints.  In recent years, these have been major factors.  Even with the 'dead space' between the boxes/ cars, a double-stack can still accomodate far more boxes - and hence revenue - in a 9,000 ft. train-length, for example, than a similar-length COFC coperation.  While the double-stack likely gets less than 2.0 times the numBer of containers as an equivalent-length COFC train, that ratio is way more than 1.0.  In a business and railroad environment where there are only so many of a fixed-number of salable train-length units or slots to be had on any given day, considerations in regard to maximizing revenue and profit will dictate that the double-stack is so much more advantageous than the COFC, even with the handicaps of some additional costs or more cumbersome operations.

David J. DeBoer in his book on intermodal trains - Piggyback and Containers: A History of Rail Intermodal on America's Steel Highway (Publisher: Golden West Books, October 1992, 192 pp., hardcover, ISBN-10: 0870951084; ISBN-13: 978-0870951084) - in one of the later chapters has an actual-cost comparison between a couple of theoretical train types - I believe that both of these contenders are included in that.  I don't have it with me right now - if I can find it tonight, I 'll try to post those figures for whatever insight they may provide.

- Paul North.

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Double stack verses conventional COFC...
Posted by Ulrich on Monday, August 10, 2009 8:47 AM

Intuitively doublestack makes alot of sense... by stacking containers you shorten the train and you improve the loaded verses tare weight ratio. But when I look at a double stack train I see alot of empty space between well cars... so each set of stack containers catches the wind and the space savings gained in stacking containers appears to be negated to some extent by the huge gaps between well cars. Compare to a standard COFC...you've got what looks like an unbroken string of containers with a relatively low center of gravity. So one has to wonder...taking into account the specialized equipment for doublestack... the greater clearances... the specialized equipment and facilities needed to on and off load...just how much more efficient is double stack over COFC?

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