A newspaper article said CN, has one of the most fluid networks on the continent. What exactly does that mean, and how is fluidity measured?
Is fluidity even a word?
CN is a system that has no fouling points, all lines keep traffic moving at all times without bottlenecks or hold ups. That’s my guess.
I checked with merriam-webster.com, and fluidity is indeed a word: the quality of being fluid. In this context, it probably means that CN does relatively better than most other systems in keeping its rolling stock – well – rolling; encountering fewer delays, bottlenecks and yard hang-ups, and thus able to get that equipment around and about the system relatively quickly.
What newspaper was the article in, and do you think the writer actually knew what s/he was talking about or was just parroting company PR? - al
Oddly enough, the article was from The Financial Times ( http://www.financialpost.com/story.html?id=1547858 ) It was in the thread about CP and KCS working together. The part about CN being sounded like PR work, in the middle of an article about CP- their biggest rival.
Is being (reletively more) fluid a sign of better management, routes, traffic patterns, business level, or just plain luck?
There is no standard measure of fluidity. There is no standard measure of line capacity, either. But they are certainly topics of great interest to RRs. The biggest stumbling block is coming up with a meaningful theoretical maxium capacity for a line.
There are lots of things RRs measure related to these, train speed, train delays, trains operated, trains held out of yards, trains held for power, crew etc. but none of them directly measure either of these.
Probably a railroad operating veteran can say, “There might not be a generally-accepted definition for “fluidity” - but I know it when I see it”. [like U.S. Supreme Court Justice Potter Stewart’s famous definition of pornography [swg] ]
That said - and I’ll note here that I’m a big CN fan - for about the last 10 years CN is big on running a “scheduled railroad” by having trip plans for all car movements in its system, and integrating those with its train schedules. I can’t quickly find an on-line reference or description of it - but they are out there, I’m sure. EDIT: Try this - description of “The Service Plan” at: http://www.cn.ca/documents/Investor-Factbook-Archive/FactBook2002_complete_en.pdf at pages 18 - 21 inclusive (Pages 20 through 23 of 80 of the “PDF” version there).
Also, CN’s published “Terminal Dwell” times" for its Major Yards and the Entire Railroad are consistently much lower than anyone else’s. I know - “definitions”, “apples vs. oranges”, and all that - but still - CN’s is only about 1/3 to 1/2 of everyone else’s, as follows for March 2009 (ranked in ascending order):
CN: 12.3 hours “Total Dwell - Major Yards”, 8.3 hrs. “Total Dwell - Entire Railroad” (and less in the more recent April 2009 weeks) - see http://www.cn.ca/documents/Investor-Performance-Measures/perf_measures_en.xls
KCS: 16.1 hrs. for Entire Railroad
CPR: 20.8 hrs. for Entire Railroad
NS: 21.3 hrs. for Entire Railroad
CSX: 23.2 hrs. for Entire Rail
I suggest the CN benefits substantially vs the Big Four US Class 1’s because it is essentially an east-west operation with much less interchange and enternal switching requirements. Of course their ventures into the US with the IC acquisition (Chicago for example) contributes to lowering their ‘fluidity’ numbers.
Is saying that your railroad is the most fluid, when there is no real way to measure it, akin to saying your railroad has the shiniest rails?
Railroad utilize a number of internal measurements to gauge their level of fluidity. Train speed is on, recrews of trains is another, terminal dwell time for cars and a number of other measures when viewed as a whole will gauge the fluidity of a railroad.
When gauging just speed, different territories generate different speeds that are dependent upon the kind of traffic being handled and the physical characteristics of the territory involved.
When you compare dwell you can’t compare railroad to railroad very accurately, you have to compare the trend of one railroad over time. This is lost on most people, so they read the statistics and make the assumptions you have made.
There are critical differences in the ways that the railroads measure terminal dwell. For example, the CN counts the dwell of cars that arrive and depart the terminal on the same train symbol, the big four US roads do not.
So if the CN and BNSF/CSXT/NS/UP each have 100 cars in the yard for a day and they both have a 100 car train that stops to change crews for an hour, identical situations, they will get different dwell. The CN will get 100 cars for 24 hours plus 100 cars for 1 hour or 2500 car hours on 200 cars or 12.5 hours dwell. The BNSF/CSXT/NS/UP will have 100 cars for 24 hours (they doesn’t count the train), so they have 2400 hrs dwell on 100 cars or 24 hours dwell. The casual observer will think the CN is outperforming the BNSF/CSXT/NS/UP, but in reality they had EXACTLY the same performance. For the last couple years the big four US roads have bounced around between 21 and 25 hours dwell.
Dave - Thanks for pointing that out. I was aware that are some differences, but not that they were that extreme.
Here are CN’s definitions, from -
http://www.cn.ca/en/investors-shareholder-carload-weekly-performance-measures.htm - click at “definitions”:
Average Train Speed
The average speed of mainline trains on CN is based on the total number of train miles divided by the total train hours accumulated. It includes system trains running on company lines and system trains operating on non-system lines under trackage/running rights or as a detour (e.g. system trains operating on CP lines in the Fraser Canyon). It excludes passenger, work and company service trains, yards, transfers, local trains, and road switchers; non-system trains operating on company lines under trackage/running rights or as a detour; and crew change time, other terminal time at crew change points, and delays at customer request.
Average Through Dwell Time
This is calculated as the average time in hours between arrival and departure at a major terminal. It includes cars departing a major terminal preceded by a train arrival, transfer or local received at interchange, as well as cars on through trains. It excludes cars on work trains, cars where Load/Empty status changes at terminal, cars with dwell greater than 10 days, cars in local constructive placement, bad orders, heavy bad orders, hold, offered or storage status, and End of Train devices. [emphasis added - PDN.]
In contrast, here are the definitions for the other 6 railroads,
Re-reading the article (above), I’m inclined to think that the “fluid” part came from the reporter’s apparent source - “Walter Spracklin, RBC Capital Markets analyst, in a recent note”. He was mentioned or quoted in 3 of the last 5 paragraphs of the story, which bracketed the mentions of CN.
As to Murphy’s question (above): I’d say that being “fluid” is a sign and the result of a fortuitous combination of all 5 factors that he set forth - until somebody comes up with a solid definition for “fluid” or “fluidity” in this context.
- Paul North.
Any railroad that is not fluid with todays reduced traffic levels is in big trouble when traffic picks up.
It’s worse than “apples and oranges”. More like “apples and crowbars”.
CN counts car dwells at crew change points/crew change only events in their dwell calculation. All the other roads exclude this. Huge difference!
CN does not play well with others…
[(-D]
Yes - that’s pretty much the scenario in Dave H. / **dehusman’**s example a couple of posts above - supported by the quoted definitions. I should have picked up on that earlier, but it wasn’t jumping out at me. And, not being on the “sharp end” on a daily basis as you operating guys are, I didn’t have the “skin in the game” that you do and as a result the intense personal interest in and insight that comes from that. Thanks for pointing it out (so kindly, too).
CN - so it would seem. I know that it used to be part of the Railroad Perfomance Measures website, but evidently CN dropped out to “play by itself” on its own website for this sometime over the last couple of years. In the meantime, it appears that the remaining 6 railroads have standardized on the common definitions for these metrics - they used to each have a separate page for their own.
Still looking for a good working definition of fluid or fluidity . . .
- Paul North.
It means you’re having smoke blown up your drawers. The reporter has no idea what he/she is talking about. He/she is stating there is a fact called fluidity which is like weight, length, or volume, which has agreed-upon, consistent, concrete terms and a standard unit of measurement. But there is not. It’s a vague, undefined term which sort-of means “the network runs more efficiently” but there’s no cross-comparison possible between networks (and even between rail lines on the same network) because network efficiency is contingent upon details specific to each network such as geography, traffic, regulatory criteria, local fuel prices, labor rates, etc. Sure, there’s people who claim they know fluidity from Adam, but I don’t believe them.
I really don’t care if my railroad has 12 hours of dwell time or 90 hours of dwell time on any specific car. I care about the return on investment on that carload. Some carloads will give you a better ROI with incredibly slow turns and some will give you a better ROI by running the wheels off them. It’s highly specific to the individual shipper, lane, equipment, and market conditions. The notion that this can all be aggregated into some sort of magic system analysis tool called fluidity is as laughable as the notion that you could predict how well children will do in their future career earnings by measuring how high they swing on the playground swing. Again, there’s people who claim they can understand ROI through arcane measurements such as fluidity, which has no consistent terms – with the implication that if they are hired to run the railway they can improve fluidity and thus ROI. I don’t believe them. They have no solid science to b
Murphy, RWM, and others -
Perhaps we’re just not asking the right people to define “fluidity” for us.
Someone at BNSF and/or CREATE seems to know what it means. They must - after all, they used it in the news release about the Corwith Yard and Corwith Interlocking Improvements = CREATE Project WA5, emphasized as follows:
(from: http://www.createprogram.org/PDF/WA5%20Benefits%2002.25.09.pdf )
Project Benefits
The upgrade and reconfiguration of the Corwith Interlocking and new signal bridge providesignificant benefits to trains moving in and out of BNSF’s Corwith Yard, one of the busiest intermodal yards in the nation handling 800,000 domestic and international containers per year. Corwith Yard is the easternmost point for BNSF’s transcontinental route from Los Angeles to Chicago, the busiest intermodal route in the nation, and the location where trains are assembled to connect with CSX and NS for destinations to the East. The improvements increase fluidity and reliability in and out of the yard and enable train lengths at the connection with NS and CSXT to be increased from 5,400 feet to 8,000 feet.
As a result of this project, train speeds through the interlocking are increased, and the speed of interchanges between BNSF and its partner railroads is improved. The number of trains that can be handled in the yard has been increased from 122 to 134 per day. Switch problems, which were a particular issue during cold weather, have been eliminated due to the improvements. Freig
RWM has it right.
Fluidity just sounds fancier than “most gooderest”, as in “CN has the most gooderest network in the known universe”.
Was it Diogenes? He carried a lantern when he was looking for an honest man.
That Corwith can handle more trains in one day than it could indicates that it is more fluid (or less viscous) than before. Is fluidity the inverse of viscosity? Or is it simply an expression created by someone who did not know any better way to express what he wanted to?
Johnny
Viscosity: Isn’t it the measurement of molecular size…and the flow rate capability.