Slack

[Deggesty]

JPS1

How does the engineer of a freight train control the slack if the train stops on an upgrade?  Downgrade?  No grade (if there is such a thing)?

On a recent trip from El Paso to Tuscon on the Sunset Limited, a Texas Eagle passenger on the through sleeper told me that he did not like to ride in the last car because of the whipping effect created by the slack running in and out.  

I am under the impression that Amtrak's Superliner cars, at least, have practically no slack action because of the lock tight couplers.  Am I correct?

 

 

 

Yes; tightlock couplers have very little, if any slack. Did he mean a side-to-side motion--which would not be caused by slack action? I do not recall a side-to-side motion the times that I have ridden in the last car on a train that came because it was the last car (the only adverse motion I do recall from that position of the car was the up-and-down motion of the foot end my berth in a roomette on the rear of the L&N's Pan American between Birmingham and Montgomery--which ended when the Atlanta-New Orleans sleeper was added in Montgomery. 

The only adverse side-to-side motion I recall comes from the rocking caused by track that needs surfacing (the worst ever in my memory came last year when the California Zephyr was detoured across Wyoming and we had to enter Denver over the Belt Line--which seriously needed surfacing. I did not remember such rocking the year before when we were detoured going west.

[PJS1]

How does the engineer of a freight train control the slack if the train stops on an upgrade?  Downgrade?  No grade (if there is such a thing)?

On a recent trip from El Paso to Tuscon on the Sunset Limited, a Texas Eagle passenger on the through sleeper told me that he did not like to ride in the last car because of the whipping effect created by the slack running in and out.  

I am under the impression that Amtrak's Superliner cars, at least, have practically no slack action because of the lock tight couplers.  Am I correct?