A Runaround?

I hear you on OCD  I took a year off deciding whether to continue with my layout I started, knowing that I will periodically be consumed with the hobby   But I really enjoy the hobby and my local club.
That is my plan for returning passenger trains from my dead-end St Joseph town/yard.  Drop cars at station, engine runs around the consist and reconnects at the previous tail end.  (But I’m also eyeing a spot where I can squeeze in a small turntable just to reverse the engine before performing the run-around.)

Bob, the only problem with the runaround is the engine will be going backwards. Not a big problem with diesels, but don’t know if that might bother you.

Generally speaking, if you have 1 O-54 loop, you’ll need a 2nd one to turn the train back around at some point.

Both a runaround and loop will limit the length of your trains to whatever will fit.

Here are some relative sizes. Obviously, the runaround and loop can be expanded and the bottom of the wye might be lengthened for larger engines.

A runaround and a (passing) siding are similar but different.  A siding allows two trains to pass with the short taking the siding.  A runaround allows the locomotive to service both leading and trailing spurs (a single entry "siding").  If you have industries that are serviced by leading turnout then you need a runaround.  The runaround can be as short as one car length.  In operations the locomotive will drop the trailing cars behind the car to be switched; pull through the runabout dropping the car to be switched; back down the main to collect the rest of the consist; move forward collecting the car destined for the leading spur; and proceeding to the spur to drop off the car.

In real life the locomotive may be required push the car miles to get to the spur.

Jan