Help me understand this ops rule mentioned in April '05 MR.

[n2mopac]

I have long been a fan of developing good ops rules for my layout that give a more prototypical feel to the layout. In April '05 MR the Information Desk column on building freight trains talks about prototype compliance and rules that can be applied to model railroads. In the box on page 90 the first prototype rule mentioned is placing long cars (over 80 feet) at the rear of a train if coupled to cars of less than 45 feet. My question is why? I understand why you would not want empty long cars at the front of a heavy train as the train forces can pull them off the rails in curves, but what to the combination of long and short cars have to do with this? I am anxiously waiting to undertand the reasoning for this rule. Thanks for you insight.

Ron

[Anonymous]

I would guess this might have something to do with the swing of the couplers - longer cars will swing their couplers out further on bends than short ones - I have a 56ft double-stack that derails on one section of track because of this. Not sure if the real thing also has this problem, but if it does it might well explain the rule. Hope this is of help!

[trainboyH16-44]

I have to do the opposite on my railway, because I have 3 89-foot flats, 2of them with truck mounted couplers,and the other with a body mounted one. I have to put a 45 foot flat between the two 89 footers to stop the truck mounted coupler from pulling the body mounted coupler car off the track.
Trainboy

[Blind Bruce]

Whether the 80 footers are loaded or not should not make any difference. They still should be at the rear for the same reason.
BB

[n2mopac]

QUOTE: Originally posted by Blind Bruce

Whether the 80 footers are loaded or not should not make any difference. They still should be at the rear for the same reason.
BB

Yes, I agree. I just meant it is most important when these cars are running light (empty). But this still does not explain why they would need to be at the end when short cars are in the train (45 feet or less). Apparently this is a prototype rule, so there must me a reasonable expalnation as to why.

Ron

[dharmon]

Try posting the question over on the Trains side. Plenty of experts over there.

Dan

[BRAKIE]

Guys,I don't know what to tell you but,I will give my first hand observations and past railroad experience..
Again look toward the prototype for the CORRECT answer..I have seen empty 86' flats next to the engine and behind the flat was a WC 2 bay hopper and these cars are less then 50 feet...
Now recall trains are PREBLOCKED per distention so again cars can be anywhere in the train coupled to any type of car.Just because a car well be 86' long and empty is no real sign it will be at the rear of the train due to preblocking.
Guys,Again,I don't know what else to tell you.

[dehusman]

The operating rules vary by railroads. What is prohibited on one road is permitted on another. You have to look at each specific railroad.

Dave H.

[n2mopac]

I posted this question on the Trains forum and got some good answers and great info from the prototype guys. It does matter, and now I undertstand better why--although the rule does vary by railroad. Anyway, for anyone interested here is the link to that thread and their replys.

http://www.trains.com/community/forum/topic.asp?TOPIC_ID=32291

Have fun.

Ron

[Eriediamond]

I've got two things to say here. First, I'm glad I'm modeling 1940's era steam and don't have to worry about where those 85 foot cars have to go in my trains cause I ain't got none. Second, I'm glad I'm following the rules by coupling my two REA express cars ahead of my long passenger cars. [(-D][(-D]