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Burning the Midnight Oil for Living Energy Independence

I've mentioned several times that there are lots of Federal Rail Authority regulations that are impediments to developing sustainable transport in the United States.

One of these is in the area of "superelevation" and "cant deficiency". Superelevation is the term used in railroading for the degree of banking provided in a turn. Just as banking a turn on a road makes it possible to take the turn at a higher speed more safely, banking the track on a railroad line makes it possible to take a turn at higher speed more safely. In US rail, its measured in the inches of the higher rail above level.

And it might seem minor technical details, but this is really critical for how much new passenger transport we can get out of our existing rail alignments for how much money.

The Basic Terms: Superelevation, Cant Excess, Cant Deficiency

When a track is "cambered", that is to say banked in this way, there is a speed at which weight is evenly distributed between the two tracks.

At a lower speed, more of the weight is placed on the lower track. This is called "cant excess", which is how much the bank would have to be reduced for the load to be balanced.

At a higher speed, more of the weight is placed on the higher track, which is "cant deficiency", or how much more the upper track would have to be raised for the weight to be balanced.

Now, suppose that you have a single track that is only being lightly used by freight, and you want to take advantage of that by adding some passing track ~ say 1 mile of passing track on average for each 5 miles of track ~ to increase the capacity of the corridor to maintain the same freight train capacity and add the capacity to support passenger trains.

Now, how fast is the freight going? If this is a mainline corridor running through fairly flat terrain, carrying a large number of fairly time-sensitive freight containers from a sea port to some inland rail yard (to be hauled away by truck to the loading dock that is the final destination of the shipment), it might be rolling along at 60mph.

But suppose that its a bulk load of coal, granite, timber or any of the other high weight, low cost per ton freight tasks that are in the US travel largely by rail. It might be trundling along at 20mph. And if 20mph has a substantial cant excess, that means a lot of that up to 33 US short tons per axle load is being carried by the lower track.

Now, consider an Express intercity passenger train that we want to bring through. Since we want it to be time-competitive with Interstate driving ~ better if feasible ~ we'd like that train to be running as close to 110mph as possible.

20mph, 60mph, 110mph ~ there is no superelevation that will be anywhere close to balanced for all three. And if the heaviest freight is the slowest, if the track is superelevated at the ideal level for Express Intercity passenger trains, the result will be massive increases in wear and tear on the track because of the cant excess for slow speed freight.

Well, if you have to build that common track to avoid too much cant excess for slow speed traffic, then in turn the speed limit on the Express Intercity train through the curve depends upon the allowed amount of cant deficiency.

And if you have a choice, you put the passing track in a segment with more than the normal number of curves, so that you can superelevate that as an Express track and allow the slow, heavy freight trains to run on track with less camber.


What is it that Tilt-Trains Do?

Tilt-trains effectively act to add extra camber to passenger car. This is important in that the speed that the train can safely operate on the track normally includes speeds that will throw the passengers around inside the train.

While it is partly a physical problem ~ it is also a regulatory problem.

That is, an important part of allowed cant deficiency is the matter of what lateral force passengers are permitted to experience by regulation. Since the most common European standard is 50% higher than the US standard ~ or at least, what I thought was the US standard ~ the allowable speed of the same tilt-train through a curve with the exact same curvature is substantially higher than Europe than it is in the United States.

Now, there is more to this than just the allowed lateral force passengers are permitted to experience: there is also the matter of the weight of the train. A train with 33 US short tons per axle (a common mainline maximum in the US) is putting 16.5 US short tons per wheel on the track when operating in perfect balance. A train with 25 US short tons per axle (a common European mainline maximum), is only putting 16.5 US short tons per wheel on the upper track at a cant deficiency when 66% of the weight is carried on the elevated track. And a train with 20 US short tons per axle (a shade over the maximum weight of many European and Japanese Express HSR sets), is only putting 16.5 US short tons per wheel on the upper track at a cant deficiency with 82% of the weight carried on the elevated track.

So while allowed lateral force is an important element of operating speed through curves, the weight of the train is also an important element, as noted by German rail enthusiast Hans-Joachim Zierke, in looking at the opportunities for an Emerging HSR corridor connecting California and the Pacific Northwest via the Shasta Route (and note that this is an unfinished project), when presenting the following example of the impact of FRA regulation on operating speed limits in the US:

The highest curve speeds in the USA are achieved by the Acela Express. For the track between New Haven and Boston, it has a waiver for operation at 7 inches of unbalanced superelevation. This means, that the Acela is allowed to use the same curve speed as non-tilting TGVs (or multiple units) in France.

Adding results to the comparison on page 4 gives the following table therefore:

  curve radius superelevation speed limit 1
Amtrak Cascades, tilting 1000 feet 4 inches 48 mph
TGV, non-tilting 1000 feet 4 inches 53 mph
Acela Express, tilting 1000 feet 4 inches 53 mph
Baureihe 411 EMU 1000 feet 4 inches 63 mph

... In the USA, trains like the type 411 EMU are not allowed to operate. US regulations require a very high carbody strength for political reasons, which adds several tons of weight to a vehicle. If this mass is added to a European tilting EMU or DMU, it is no longer safe to operate at 11.8 inches of unbalanced superelevation, because the maximum safe axleload is exceeded.

The Acela Express is built to these strength standards. It is nearly double as heavy as European or Japanese tilting trains.  Instead of restricting the axleload to 16 tons or less, the powercars weigh 25 tons per axle. No safety authority would allow values like those for the German 411 or 610 for this train, because the forces at the wheel-rail contact point would be too high for safe operation.

As a result, the "Acela Express" looses about half an hour between New York and Boston, compared to best practice in tilting train usage. (It also looses at least half an hour, compared to the calculations of US railroad engineers in the 1960s.) If this half hour of running time from New York to Boston needs to be cutted away by infrastructure investment instead, a three-digit number of millions in additional public investment will be needed at least. A similar situation will be found with almost all upgrade projects for curvy track.

In the US, the standard allowed cant deficiency of passenger rail has been set by, first, the safe operating limits of the train itself and, second, by the amount of lateral force placed on the passenger inside the train. In practice, the second is the main constraint, and this results in a much lower allowed amount of cant deficiency in the US than in Europe.

That is, even if tilt trains were acquired that were safe to operate at extremely high cant deficiencies, and which were allowed in Europe to operate at those high cant deficiencies, the existing regulations in the US would have substantially reduced the speed limit going through a curve.


The Importance of Speed Limits Through Curves

To get an idea of the importance of speed limits through curves, consider the diagram to the right. This is the modeling results (pdf) of the operating speed along the 110mph of the planned Ohio Hub 3C corridor.

When the line drops all the way down to 0mph, that is, of course, a stop at a station. However, you can see all the notches where the train slows down to take a curve at a slower speed.

Consider one of the notches where speed has to be dropped down to 40mph. In the speed profile, notice that most of the time is spent dropping down from 110mph to 40mph and accelerating from 40mph to 110mph.

That is, of course, a route profile, not a trip time profile. When we think about the average speed of the service, the slowest sections of a route loom the largest.

Consider, for example, a train that runs 50 miles at 40mph and 50 miles at 110mph. A simple average of the two speeds is 75mph. But the slow section requires 1.25 hrs while the fast section requires 0.46hrs, which is a total of 100mile in 1.71 hrs, or about 59mph. More of the time is spent at 40mph, so it looms larger in the average speed.

And consider the difference between accelerating the slower leg by 10mph and accelerating the fastest leg by 10mph:

  • 50 miles at 40mph and 50 miles at 120mph is 100 miles in 1.67 hrs, or ~60mph
  • 50 miles at 50mph and 50 miles at 110mph is 100 miles in 1.46hrs, or ~68mph

Given the importance of the amount of slow down required through curves, the table that Hans-Joachim Zierke shows represents the US tying one hand behind its back in the race with Europe and Japan to achieve sustainable transport.


However, the Regulations May Be Fixed

OK, now. Put yourself in my shoes. I am googling around for information on cant deficiency and Federal Rail Authority regulations in mid-November, when I stumble across the following notice in the Federal Register:

Vehicle/Track Interaction Safety Standards; High-Speed and High Cant Deficiency Operations
FRA is proposing to amend the Track Safety Standards and Passenger Equipment Safety Standards applicable to high-speed and high cant deficiency train operations in order to promote the safe interaction of rail vehicles with the track over which they operate. The proposal would revise existing limits for vehicle response to track perturbations and add new limits as well. The proposal accounts for a range of vehicle types that are currently used and may likely be used on future high-speed or high cant deficiency rail operations, or both. The proposal is based on the results of simulation studies designed to identify track geometry irregularities associated with unsafe wheel/rail forces and accelerations, thorough reviews of vehicle qualification and revenue service test data, and consideration of international practices.

I was even more excited when I looked at the details of the proposal, and found that both the allowed amount of superelevation and the allowed amount of cant deficiency were proposed to be increased.

As I understand it, the superelevation rule is also being tightened. The existing phrasing was 7″ on a related measure, which when combined with allowed tolerance from design standard translated into a maximum 6″ superevelation. The new rule states it in terms of superelevation as a design standard, with tolerance in operation defined in terms of the design standard, so 7″ superelevation on express track becomes possible.

There is a standing balance requirement on rolling stock, since it would be unsafe to operate a train that would be in danger of tipping over if it was necessary to come to an emergency stop, so its quite possible that not all rolling stock would be permitted to use a corridor that was superelevated for Express service ... but to me, you do not want every coal and granite train to qualify to enter an express bypass anyway.

For a curve with a 1000ft curve radius (which is a 5.75 degrees of curvature), under the old rules, outside of the North East Corridor, the best that could be reasonably expected would be 9" of combined camber, from 4" of superelevation of the track and an allowed 5" of cant deficiency, even with a tilt train. That means that the passenger service ~ even if its a tilt train ~ would be limited to 47mph through that curve. A freight train, which is limited to 3" of cant deficiency, and indeed all other trains limited to 3" cant deficiency, would be limited to 41mph (those are the ~40mph curves in the above speed profile).

Why is the Northeast Corridor singled out there? Because it was granted a waiver, that allowed both the Acela tilt train and the NEC Amtrak Regional trains to operate at a higher cant deficiency than generally allowed for.

Under the new rules, which would be nationwide, if an express section of track can be superelevated to 7", and a tilt train can operate with 8" of cant deficiency, that is 15" of combined camber, which would allow a express freight train to run at 49mph around the same curve, and a passenger tilt train to run at 61mph.

Indeed, one thing that this new regulation implies is that existing Amtrak services operating in mountainous terrain along "river routes" with the large number of curves that this implies can receive a substantial speed upgrade even before raising the top speed limit above 79mph. Also, Amtrak services that will be running on any segment of track upgraded for use by an Emerging HSR 110mph service will be in a position to take advantage of the higher speed track as soon as it is ready for service.


What Else Needs to be Done

Since what I have been reading is the rule proposal, but the final rule date is given as December 2010, I am not quite sure what has come of this, and due to broken links at the Federal Register, its a bit difficult to work out. That is something I am following up by email to the listed contact.

However, if anything like the proposed rule actually takes affect, this implies a substantial upgrade in the possibilities for using our existing rail corridors. Since this is being done by regulation rather than by waiver, it can be put to use across the board, rather in the piecemeal way implied by waivers of regulations. And since it is being done by regulation, it provides a standing target for the manufacturing of a new generation of more effective and efficient passenger train.

Of course, this is not everything. As Hans-Joachim Zierke notes, the "build it like a tank" approach to crash survival results in heavier trains, while the European and Japanese approach of "design the system to avoid crashes" results in lighter trains, and lighter trains are better able to take advantage of these new cant deficiency regulations than heavier trains.

But this is a good step. And its a first step that may well have been the result of a Republican Take-Over ... that is, in 2009 in the Department of Transportation, when Roy LaHood was made Secretary of Transportation and the eight year assault on rail transport by the Bush administration came to an end.


Midnight Oil ~ Kosciusko

Older than kosciusko
Darwin down to alice springs
Dealers in the clearinghouse
The settlements explode

High up in the homelands
Miners drive across the land
Encounter no resistance
When the people block the road

Old than kosciusko
Dry white seasons years ago
Darkness over charleville
The fires begin to glow

No end to the hostility
Now they wanna be somehwere else
No stranger to brutality
Now they'd like to be someone else
...

Originally posted to BruceMcF on Sun Jan 16, 2011 at 07:32 PM PST.

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Comment Preferences

  •  OK, so its way late ... (29+ / 0-)

    ... at least it really is still Sunday Evening. So the Sunday Train, even if late, is hereby declared to be back in service.

    End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

    by BruceMcF on Sun Jan 16, 2011 at 07:20:05 PM PST

    •  I still think (7+ / 0-)

      you should be published in Harper's. Or MoJo.

      "One should always be a little improbable." - Oscar Wilde

      by Miep on Sun Jan 16, 2011 at 08:53:52 PM PST

      [ Parent ]

    •  Sheesh, I missed it till it was rescued (1+ / 0-)
      Recommended by:
      BruceMcF

      nice work, Bruce.

      "Play it LOUD Robbie, Play it fucking loud" Dylan

      by NearlyNormal on Mon Jan 17, 2011 at 09:06:54 PM PST

      [ Parent ]

    •  Thank you for this (3+ / 0-)
      Recommended by:
      arlene, BYw, ban nock

      As someone who will be directly impacted by passenger rail development in the PacNW, I truly appreciate your work in explaining all of these things.  It helps me have a better conversation with the people who say they know what they're doing.  It also helps me better support my people in Rail.  

      I truly believe that our focus should be on building true high speed rail, not this half-assed version of "higher" speed rail they're talking about today.  It will never cost them less in the future to build true high speed rail today.  Never.  Do it right the first time, people.  Please.  

      •  I truly believe that ... (1+ / 0-)
        Recommended by:
        mamabigdog

        ... our goose is well and truly cooked unless we make progress across the board. I've never bought the idea that somehow we will make more progress on Express HSR corridors because we have not built Regional HSR where it makes sense, or the idea that we will make more progress on local sustainable transport if we set aside intercity sustainable transport.

        End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

        by BruceMcF on Tue Jan 18, 2011 at 09:48:50 AM PST

        [ Parent ]

  •  If there's a Sunday train, I'm on it. (13+ / 0-)

    Preferably in the club car.

    If you think you're too small to be effective, you've never been in the dark with a mosquito.

    by marykk on Sun Jan 16, 2011 at 08:20:15 PM PST

  •  hey (12+ / 0-)

    good geeky stuff! thanks for taking the trouble to put this together!

    Scientific Materialism debunked here

    by wilderness voice on Sun Jan 16, 2011 at 08:20:56 PM PST

    •  No worried, that's what they pay me for. (11+ / 0-)

      ... hey ... wait a minute!

      End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

      by BruceMcF on Sun Jan 16, 2011 at 08:23:45 PM PST

      [ Parent ]

      •  Srsly, Thanks (4+ / 0-)
        Recommended by:
        BruceMcF, Calamity Jean, BYw, ban nock

        When I've seen the discussion of cant deficiency, superelevation, and so forth on The Transport Politic blog, it's always made my mind glaze over.

        Thanks for making your explanation so clear that even a lay reader like me can understand the subject.

        And I share your excitement about the pending rules change. It looks to me like this could shave the trip times for almost all the conventional Amtrak lines.

        Taking half an hour (or dare we hope for more?) from some schedules would allow serving some cities that are barely served at all now.

        Pittsburgh, for example, currently can be reached at about 10 minutes before midnight, after an eight (8) hour run from Washington, D.C. with no delays.

        Take 30 minutes out of that schedule gets you into Pittsburgh at 11:20, but squeeze another 20 minutes out and the arrival could be at 10:59. Marketing a seven hour ride that gets you into Pgh at 11 instead of at midnight is gonna be easier.

        On a shorter route, like Chicago-Detroit, squeezing half an hour out of a schedule might even allow using the equipment on one train to make an additional one-way trip (or one roundtrip Chicago-Kalamazoo) instead of only one Detroit roundtrip per day. A shorter trip time and an additional frequency would see ridership soar.

        The Amtrak system of conventional trains could be transformed by these developments.

        •  I've previously noted that ... (2+ / 0-)
          Recommended by:
          BYw, ban nock

          ... untying the Indianapolis / Chicago Hoosier from the Cardinal could allow the current three Cardinal services a week to DC, ticketed through to NYC on NEC Regionals, and also three Capital Corridor services a week that could run through Cleveland and Pittsburgh in the evening rather than after midnight.

          But the Cardinal is plagued by late running, and anything that would allow more Cardinal services to catch up after a delay would make that kind of operation far more practical.

          End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

          by BruceMcF on Mon Jan 17, 2011 at 12:36:05 PM PST

          [ Parent ]

  •  Leaving this up for my railfan spouse (7+ / 0-)

    to look at when we come home from dinner -- great stuff.

    Oh, you might be interested to know that China is in the midst of expanding their HSR trackage; a friend of ours came out from NYC and showed some of his current shots (his wife is from Guangzhou and they go over once a year to visit her family; they actually bought an apartment where her mother lives and where they stay when they're visiting). Doesn't seem to be killing their economy any...

    Now to try to end the wars we ask our gay and straight soldiers to fight. -- Chris Hayes

    by Cali Scribe on Sun Jan 16, 2011 at 08:28:28 PM PST

  •  Its a shame what we did to trains (7+ / 0-)

    In the 1920's Crack Passenger trains could do as much as 120-125 mph (Penn and CB&Q), Priority freights did 100mph.

    The curves in the 4 track main line NY-Boston area really cant be straightened out, Curve @ Bridgport Conn is whacked, right next to the Ferry dock. These rail Lines were laid out in the 1830-1840's and these areas are not suitable for 200-300 mph service..

    IMHO a new right of way needs to be laid out, roughly 30 miles inland, from Bangor Maine, south to at least DC.

    FDR 9-23-33, "If we cannot do this one way, we will do it another way. But do it we will.

    by Roger Fox on Sun Jan 16, 2011 at 08:37:54 PM PST

    •  However, as noted ... (10+ / 0-)

      ... sustained speed and top speed are two quite different things.

      One reason the Zephyr from Chicago to Denver had such high sustained speeds is that on those alignments, there really are quite long stretches that are almost completely straight, and the curves are often quite small curvature. The other reason, of course, is because that was before the "single track revolution", and there was separate local and express track most of the way, so the curves of the express track could be cambered for higher speed operations.

      End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

      by BruceMcF on Sun Jan 16, 2011 at 09:05:51 PM PST

      [ Parent ]

      •  And The Zephyr was light weight allowing for (3+ / 0-)
        Recommended by:
        arlene, BruceMcF, BYw

        good acceleration back to Speed. But your right about the routes, also a line IIRC from Chicago south to umm, I wanna say south to Atlanta? Was quite fast. But the Pennsylvania was noted for its 4 track main line and 125 mph steam engines.

        A lot of freight that carried Milk, mail and fresh produce received priority and 2-10-2 decapods that could hit 100mph.

        FDR 9-23-33, "If we cannot do this one way, we will do it another way. But do it we will.

        by Roger Fox on Mon Jan 17, 2011 at 12:15:05 PM PST

        [ Parent ]

    •  I should note that ... (6+ / 0-)

      ... they are actually working on straightening out some of the Connecticut curves that cause problems ~ there is a substantial slowdown of the Acela in particular in Connecticut since the tracks are too close together to allow the Acela to use its tilt. This new regulation will only make a marginal contribution there, because the Acela already operates under a waiver that brings it close to the proposed new standard.

      However, the real bottleneck in Connecticut on the NEC is the shoreline bridges which have a capped number of Acela services, so an inland Connecticut Acela service would allow for more total services. Whether that would go up to Springfield MA and then to Boston, or join the NEC at Providence to run up to Boston (which is one of the few full speed sections of the Acela route), that requires a substantial amount of local input.

      There is, in any event, substantial reason to have two Regional HSR corridors and one Express HSR corridor running north of NYC through to Boston, via New Haven, Hartford and Poughkeepsie, and which one of the three is the Express HSR and which two are the Regional HSR are not the kind of question I would get too concerned about.

      End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

      by BruceMcF on Sun Jan 16, 2011 at 10:46:48 PM PST

      [ Parent ]

      •  Connecticut (5+ / 0-)

        CT was always where the trains slowed down, even in the days when I was doing a weekly commute between Boston and NYC back in the 1970s.

        Solar is civil defense. Video of my small scale solar experiments at solarray.

        by gmoke on Sun Jan 16, 2011 at 10:52:55 PM PST

        [ Parent ]

      •  I really doubt the tracks are too close (0+ / 0-)

        that is dictated by fed standards across the country, its the curves, they are of too small a radius, causing more overhang of longer cars like the standard 85 ft passengers cars.

        See the Current "Plate" Standards, is what I think its called.

        FDR 9-23-33, "If we cannot do this one way, we will do it another way. But do it we will.

        by Roger Fox on Mon Jan 17, 2011 at 12:20:33 PM PST

        [ Parent ]

        •  No, tilt trains need more than the ... (1+ / 0-)
          Recommended by:
          BYw

          ... 14' separation centerline to centerline in place in CT. Running with the tilt locked puts the Acela in the same boat as the Amtrak NEC regionals.

          Of course, the NEC is in one of the few parts of the country were ROW tends to be already built out. In places like Ohio, there tends to be ample room in the ROW ~ the original Ohio Hub 110mph Engineering Assessment (6mb pdf) noted:

          A key engineering assumption, adopted for this Study, involved the centerline offset between an existing high density freight track and a new FRA Class 6, 110-mph track. Both NS and CSX requested that new Class 6 high-speed passenger tracks be constructed at a minimum 25-foot centerline offset from the adjacent freight track. However, in order to accommodate possible future capacity expansion, the 25-foot offset was increased to a 28-foot centerline offset. The 28-foot offset would allow a future siding with 14-foot track centers to be constructed between the new 110-mph passenger track and the adjacent freight track. Based on the field reviews the costs associated with the 28-foot offset were estimated and included under the line item "High-Speed Rail (HSR) on New Roadbed and New Embankment." This line item includes new track and ties, track ballast, sub ballast and the earthwork required to build a four-foot-high embankment

          End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

          by BruceMcF on Mon Jan 17, 2011 at 12:31:02 PM PST

          [ Parent ]

          •  Plate B is 15'1" high and 10' 8" wide (0+ / 0-)

            http://en.wikipedia.org/...

            What you are saying is that Plate B as a maximum is obsolete, of course it is.

            FDR 9-23-33, "If we cannot do this one way, we will do it another way. But do it we will.

            by Roger Fox on Mon Jan 17, 2011 at 01:22:58 PM PST

            [ Parent ]

            •  It depends on the tilt-train technology ... (2+ / 0-)
              Recommended by:
              Roger Fox, BYw

              ... the kind that have the passenger compartment suspended within an outer shell and tilts inside the shell would, of course, not encroach on the loading gauge. The kind that tilt the whole body of the passenger train (as shown above), have a wider loading gauge going through a curve.

              After upgrading the speed of the level crossings, this is one of the main things involved in upgrading to tilt-trains in conventional rail corridors.

              I don't think that 25' centerlines are actually functionally required ~ I think that is more to make the insurance company happy ~ but more than 14' if the curve is going to involve a substantial tilt.

              Of course, tilt mechanism makes a difference as well: the Japanese mechanism shifts the train more to the "outside" of the curve, and the common European mechanism more to the "inside".

              End 2010 with Lesbian Creative Works from ALC Publishing on your Holiday list.

              by BruceMcF on Mon Jan 17, 2011 at 01:53:51 PM PST

              [ Parent ]

  •  BTW, Bruce (5+ / 0-)

    the paper was a critical success, although I was not pleased with it, which is why I didn't send it. Your input, however, was invaluable.

    If you think you're too small to be effective, you've never been in the dark with a mosquito.

    by marykk on Sun Jan 16, 2011 at 08:39:35 PM PST

  •  technology explained for the lay person, thanks (5+ / 0-)
    Recommended by:
    RunawayRose, eeff, Woody, BruceMcF, DWG

    I hear that train a cumin,

    "Don't fall or we both go." Derek Hersey 1957-1993

    by ban nock on Mon Jan 17, 2011 at 04:49:25 AM PST

  •  Thanks for an interesting diary. (0+ / 0-)

    Pity can't T&R due to silly time limits. What's the point of rescuing a diary and then putting it in a time lock ?

    One bitter fact is two bit hacks populate the third rate fourth estate who are truly the fifth columnists.

    by amk for obama on Tue Jan 18, 2011 at 01:33:12 AM PST

  •  I'm hoping the new format of DK4 (2+ / 0-)
    Recommended by:
    BruceMcF, BYw

    Will make diaries such as this one more accessible for viewing days, weeks, months, even years after you hit publish.

    Glad too I saw this on rescue so I could add another comment.

    Before I read this I'd no idea of cant or how it affects rail traffic. Of course when you think of it, it's obvious, but who thinks of it. To think that a change of standards could have such a wide ranging affect.

    "Don't fall or we both go." Derek Hersey 1957-1993

    by ban nock on Tue Jan 18, 2011 at 04:06:18 AM PST

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