Switching on GEC's layout

[jwb]

One thing I'm curious about, why are the cabooses sometimes right behind the locomotive, and other times on the back of the train? where is it more appropriate?

I think it depends on what makes switching easier, and minimizing the time taken in walking back from throwing switches. In the "real" days of rail operation, it was a brakeman's duty to stand on the rear platform and keep an eye out for new gouges on the ties, which would signify a derailment -- one reason the caboose was on the rear. As trackside detectors became more common, this was less important.

I learned about another issue on a Southern Pacific branch in the LA area: in the 1980s, when cabooses were being phased out, the local had a caboose if the power was an SW1500. If the power was a GP9, it didn't have a caboose. The reason was that theGP9 had a toilet, while the SW1500 didn't, so the train ran with a caboose simply to provide a toilet. How this has been handled in later years, I don't know, but SW1500s were common in the LA area until just a few years ago, with no cabooses.