Simple enough! That's where you shove a string of cars with no one on the point to observe what's in front of the movement.

Like I said, I saw it happen numerous time in a small ewepee yard nearby - no one watching where they were going. They had to be assuming that they had enough room. I never actually witnessed anything happen, but I often heard very very LOUD "hard-couples"! I did once see two cars that had previously been sideswiped and derailed in the ladder at the other end. Fortunately, it wasn't the propane tank that was hit in the side and rolled over!

As far as I understand, it is against the rules of all railroads. But after watching these short handed crews work (ONE or two men on the ground) from up on the adjacent hill, and seeing how long it takes to get anything done; it is no wonder they try such a stupid thing - or are pressured into it.

After all, UP wants its work DONE, even if in the infinite wisdom of their bean counters, they won't hire enough people to do it right - and safely! An occasional accident is just part of the necesary cost of doing business - as in Gibson, Oklahoma. But hiring enough people to get it done safely - apparently ISN"T!