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AAR Car Types

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  • Member since
    July 2006
  • From: Southern Quebec, Canada
  • 868 posts
AAR Car Types
Posted by Guy Papillon on Sunday, November 10, 2013 3:04 PM

What is the difference between HMR and LO cars?  The definition of LO looks like a covered hopper to me.

Guy

Modeling CNR in the 50's

  • Member since
    July 2006
  • 3,312 posts
Posted by locoi1sa on Sunday, November 10, 2013 4:36 PM

Guy.

 The HMr is a regular old open top two bay hopper with a roof added. The LO is a special service car with weather tight top covers and unloading fittings. It may not have bottom dump doors but instead be equipped with vacuum or pressure unloading fittings. It is also not compartmentalized.

          Pete

 I pray every day I break even, Cause I can really use the money!

 I started with nothing and still have most of it left!

  • Member since
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  • From: Canada
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Posted by cv_acr on Monday, November 11, 2013 9:21 AM

LO is in fact the code for any covered hopper - that is, a car built as a fully-enclosed self discharging car. Pete's (LocoI1SA) description is a good technical description of what a covered hopper really is. (Although some covered hoppers ARE in fact divided into separate compartments.)

HM is a 2-bay hopper car; the R suffix indicating the addition of a (usually removeable) roof or cover.

So yeah, exactly like he said above.

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Posted by chutton01 on Monday, November 11, 2013 10:34 AM

Considering all the different types of covered hoppers, from unloading methods to differences in loading hatches to various interior coatings and arrangments, etc, it's rather pathetic that what is one of the largest categories of railcars on modern North America rails has to make do with a single AAR category code 'LO' - conversely, open top hopper cars seem to have have a slew (13) of AAR codes.

Yes, I know railroads/shippers use UMLER codes now, which is much more useful for detailed covered hoppers designation, but still, after all these years...just one mech designation "LO"? Especially considering that the UMLER code uses the second digit of it's 3 digit code to distiguish between "LO" (fixed roof) and "HTR" (removable roof)

  • Member since
    July 2006
  • From: Southern Quebec, Canada
  • 868 posts
Posted by Guy Papillon on Monday, November 11, 2013 4:14 PM

Thanks to everyone. I am now able to clearly identify all cars in my fleet by its AAR code.

Guy

Modeling CNR in the 50's

  • Member since
    September 2010
  • 21 posts
Posted by Atlanta Dave on Friday, November 15, 2013 9:57 AM

In many cases railroads or shippers do not use the actual UMLER codes but a translation.  Depends on the software they use to manage what they do.  An example would be the code B312 which is the UMLER code for a general purpose 50' boxcar.  Many railroads and/or rail customers never see B312.  Instead the software translates that code to something more usefule such as "B5" or "B5S".  (B5S - Boxcar, 50', single door).

 

 

  • Member since
    July 2006
  • From: Northfield Center TWP, OH
  • 2,538 posts
Posted by dti406 on Friday, November 15, 2013 11:53 AM

You guys forgot the LC designation which is a boxcar with Roof Hatches for loading.

URL=http://s765.photobucket.com/user/dti406/media/MiscCars003.jpg.html] [/URL]

Rick J

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