buffer car

[storminorman]

Again today I saw a train rolling past that had a boxcar right after the engines and one at the very end. All the rest were tankers....black...possible LP cars. Do they do this as a simple crumple zone in this case?

 

[Rader Sidetrack]

Again today I saw a train rolling past that had a boxcar right after the engines and one at the very end. All the rest were tankers....black...possible LP cars. Do they do this as a simple crumple zone in this case?

If the loads are tanks, they may carry hazardous materials (Hazmat). If so, there are specific rules for idler car placement depending on the type of hazmat material. Here's a link to a UP document about this issue.
http://railtown.team.parks.ca.gov/volunteers/Document Library20/1/UP Hazmat.pdf

If the material is not hazmat, but capable of shifting in an accident, perhaps like steel pipe, there there also may be idler cars indeed employed as a "crumple zone."

 

[storminorman]

Thanks! Yesterday was the first I saw an extra car at the front end, bit often see them on the end of a full tank unit. Makes sense I suppose.