Heritage Units-Brake Stick Holder

[NW Mailing List]

Jimmy,
I've never had a satisfactory answer, either.  The best I've been able 
to piece together (based in large part of the fact that cars with 
constant contact side bearings are not restricted) is that empty hoppers 
and bulkhead flats are fairly light and present a large sail area which 
can lift one end of the car slightly.  The lift reduces the weight on 
the front truck enough to allow the car to rock and sway, increasing the 
chance of the car derailing.  Constant contact side bearings would help 
to prevent that problem, which is why (in my theory) they are not 
restricted.

Of course, that's just my un-scientific theory.  I really do not know.  
I do know that the 45mph restriction made a lot more of a difference 
when the track speed was 60 rather than 50, so I think the restriction 
is an overly cautious holdover from an earlier era.  I have no 
explanation for the lack of a restriction on a solid empty train, except 
perhaps that in theory the crew would be able to see what was going on 
and reduce the speed as needed, while they probably would not see a car 
a mile back in the train.

Ken Rickman

On 7/25/2012 6:31 PM, NW Mailing List wrote:

> I still haven't gotten an answer as to why empty hoppers are 

> restricted to 45mph if not in a solid train.

> Jimmy

-- 
Kenneth Rickman
Salisbury, NC
Fundamentalism: from "Fund" : Give me money, and "Amentalism": No brain.

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