Glen Labah  wrote:   
   > In article ,   
   >  "conklin"  wrote:   
   >   
   >> You are irrational once again.  If Metro-North needs to follow X, Y and Z   
   >> for safe transport of passengers, then freight RRs which carry oil need to   
   >> have track as good as Metro-North.  Or, are you saying that Metro-North   
   >> needs no new program because you say so?   
   >   
   >   
   > The mainline railroads already are doing these types of track   
   > inspections - or rather the Federal Railroad Administration does the   
   > inspections with its own cars:   
   >   
   > http://www.fra.dot.gov/Page/P0120   
   >   
   > In some cases the railroad companies have their own track inspection   
   > cars to do track inspection work, or they have other methods of doing   
   > this work.  The FRA is only supposed to verify their methods are working.   
   >   
   > About two years ago I attended a SoundTransit meeting where the expense   
   > of track inspection came up, and one of the contractors said the   
   > cheapest way of doing the regular track inspection was, rather than have   
   > a special track inspection car, to simply put the required equipment on   
   > some of the cars already operating in regular service.  They said they   
   > were already doing this on a few other commuter railroads.   
      
   I have a hard time believing that is correct. The equipment on a track   
   geometry car is expensive, so you want to maximize its utilization. On the   
   other hand, it requires several technicians to operate, so you don't want   
   to test the same piece of track over and over again several times a day.   
      
   As I said, "autonomous" systems like the ones mentioned in the press   
   release are probably not using lasers to measure track gauge, profile, and   
   cross-level. The ones used on freight locomotives are just a set of   
   accelerometers and a GPS, hooked up to a simple signal processor to look   
   for unusually high accelerations, hooked up to a cell phone to report such   
   events. Certain types of accelerations are somewhat predictive of rail or   
   track problems generally, but a follow-up visual inspection is required   
   before you know what, if anything, is the issue.   
      
   On the other hand, one thing that the FRA HAS experimented with is putting   
   one of their geometry cars on the tail end of revenue passenger trains,   
   instead of running it as a separate train. This is cheaper, gives a higher   
   utilization, and avoids the operational problems of finding locomotives,   
   crews, and an open slot for another high-priority train running at   
   passenger speeds. The disadvantage is that you only go where the passenger   
   train goes - you don't get to decide (or even know ahead of time) which   
   tracks will be tested, you can't stop and field-verify an unexpectedly   
   severe defect, etc.   
      
   There is also a liability and / or regulatory issue with operating this   
   way. The FRA normally requires any federal track defect to be protected as   
   soon as it is discovered (usually with a slow order). When a geo car runs   
   as a separate train during daylight hours with plenty of advance warning,   
   the necessary maintenance personnel can be made available both in the car   
   and on the ground to ensure that happens. On long-distance Amtrak routes,   
   where the car may come through at night and doesn't necessarily stop at the   
   edge of each maintenance supervisor's territory, that's harder to   
   accomplish. In my experience, the FRA will give some waivers to help   
   alleviate this problem (e.g. 24 hours to inspect and protect), but there is   
   still a big liability concern if a geo car has reported a problem and you   
   haven't done anything to protect it.   
      
   Dan   
      
   --- SoupGate/W32 v1.03   
    * Origin: LiveWire BBS -=*=- UseNet FTN Gateway (1:2320/1)