My first question is: would a

First off, a single engine arriving a yard with a handful of cars probably isn't going to be arriving at a yard with AD tracks, so the question is most likely moot.

The inbound train can put them in any track the yardmaster tells him to put them in.

What is prohibited by most contracts is the SWITCHING of the cars.  That work normally belongs to the yard crews.  Now there may be be exceptions depending on whether the local is itself a yard crew, or its a local crew, or whether there is a yard crew on duty at the time the local arrives.  If the local is a yard crew, then it can switch anything up.  If its a local crew and there are no yard engines on duty, the local can switch its own train or cars associated with its work.

The engineer wants the engine facing so he can see the crew.  That means he wants to be on the same side as  the switch ladder.  He wants to be able to see the switchmen working along the ladder so they can pass him signals.  If he is on the off side, then he can see them, they can't signal him to move.  If the engine is forward, great, if the engine is backwards, not as good but that's how it has to work.  Hood engines are designed so the engineer can easily operate it in reverse.

In the top example the SW type engine is facing forwards, but the engineer (red dot) can't see the switchman (green dot) over the hood of the switcher and boxcar he's coupled to.  In the bottom example the engine is backwards, putting the engineer on the same side as the ladder, can now easily see the crew anywhere along the ladder.

Dave, Thanks for the quick

Dave,

Thanks for the quick reply and good info. I never considered the engineer's sight path to his switchman. In your second drawing, what happens when the boxcars have made the turn onto one of the stub tracks but the engine is still on the ladder? If the task is to uncouple and drop the lead car, or if they are pulling a car from that track, how does the engineer get his signals? He is now on the opposite side from the action and must look across the cab through the opposite window.

On my first question I was thinking of my layout yard which does have designated A/D tracks but I get the idea. The yardmaster is the boss for the returning local. In a way it's Rule One "It's my railroad and I'm the yardmaster."

Thanks for your help.

Charlie

Switching

In real prototype switching the cars are cut off in motion, and are uncoupled while moving on the lead, and roll into the tracks.  The switchman doesn't go down into the track.  If for some reason he would, there are two men on the lead, the "pin puller" who uncouples the cars and the "field man" who lines the switches.  The pin puller can pass signals from the field man.

A/D Tracks

As Dave alluded to, generally only really big yards actually have A/D tracks - and those will be used for longer mainline trains that arrive. A short local or industrial job that's terminating could arrive on any track.

The prototype yard that our club models (Sudbury, Ontario) is like many such yards. While large for a model layout, it's actually a fairly medium size yard. 20 tracks (in the model version, I think the prototype only has 2 or 3 more than our version), no dedicated A/D tracks. A number of locals are based out of the yard and they just get built and come in on any track that's convenient to the yard master.

In my home town of Sarnia, Ontario, CN has a fairly large yard complex. There's a sort of "main" yard (known as the "A" yard), that has a set of A/D tracks for longer mainline trains that arrive/terminate or set off pick up large blocks of cars, plus a large set of classication tracks. There's also a secondary set of yard tracks (known as the "C" yard for CN's car control zone labelling) which is still bigger than the first prototype I mentioned, which is used for sorting and storage of cars for the heavy amount of local industry (mainly petrochemical).cars for local assignments are organized here (C yard), and when the locals (note-these "locals" are all yard assignments so they can do their own switching to prepare their trains in the "C" yard) return they bring their cars to the A yard for sorting to outbound trains and then park their power and end their assignment.  CSX also has an isolated operation in town (which is basically like a shortline operated by a class I). They have a pair of small yards for sorting and storing local cars, only run one job at a time. No formal A/D tracks anywhere, just a bunch of tracks that can be used as needed. The whole operation is treated as yard/non-main-track. They also run one of their jobs over to CN once a day to exchange interchange cars. They come onto CN tracks, and run directly into the "A" yard and set off and pick up their cars directly from classification tracks in the yard.

Seeing the Engineer

Adding to what Dave has already presented, a brakeman or switchman (whoever is on the ground) knows that the engineer has to see him.  Therefore he will position himself so that happens.  There may be an occasion where there is no person to pass signals, so the brakeman needs to move himself to a spot where he can see what is happening, but also where the engineer sees him.  If he can see the engineer, obviously the engineer can see him.

Bottom line:  the crew works as a team, doing what is necessary to get the job done, and do it safely.

OK, Guys. Perhaps I elevated

OK, Guys. Perhaps I elevated my puny yard (superelevated?) to a status I doesn’t deserve by giving it AD tracks, but I find them useful when dealing an interchange train with long cuts from/to some remote place. In fact they may be misnamed since they are really only two double ended sidings closest to the main (tracks 1 and 2). I added them in the planning stage because the “experts” said I should. The picture below is the yardmasters view of the control panel. The red and blue tracks are the main that circles by the yard and an industrial area to the right. The steam and diesel engine service area is also to the right. An auxiliary yard for overflow and storage is to the left. The second picture is the actual yard on the layout.

I 

I appreciate the inputs from those with actual railroad experience. I wasn’t sure of the rules and contracts regarding division of labor among the various crews. I just made sense that a road switcher, particularly one returning from a short local turn with a few empties, could spot directly to a ladder track but I wasn’t sure. Thanks for the enlightenment. Same is true for the forward/reverse use of the yard switcher. I’m much smarter now.

Charlie

Track Diagram

Actually that's a nice little design...

Do the "yard leads" re connect to the mains at any point at the ends, or they "stub" tracks at each end?

Because if they're stubs, the way Tk 2 connects in there short of the west-end crossover, makes Tks. 1&2 nice tracks to use for receiving and building trains to/from the "west" end of the yard. It would be really awkward getting a train from that end in or out of any other track(s), involving backing up movements.

Trains to/from the "East" end can easily run right into/out of Tks 3-5, with the progressively shorter tracks to the rear being less ideal due to the short capacity. 8 is obviously a "runner" track to be kept clear.

Chris, Both yard leads are

Chris,

Both yard leads are dead end stubs. The "west' lead actually becomes a programming track with some electrical switching. When I laid out the yard I chose to make it semi unidirectional. The favored directions are arrival from the "west" and departure to the "east". This allowed somewhat longer tracks. The two crossovers permit approach from either direction. Just to the east is a loop that ties the red and blue tracks together and serves as a turn around. This allows a train built and departing to the east to circle the loop and leave the yard area to the west, or cross over and leave toward the west. Confusing but it works well. The loop circles an industrial area including two parallel sidings, and really serves as part of the yard. I'm presently trying to decide if the industrial area is a separate location served by a local freight or an industrial area attached to the yard and served by the yard switcher.

Occasionally a train will enter from the "east" or depart directly "west" from the yard but it is more difficult as you observed. IF I had had more room I would have made the yard symmetrical and similar to the eastern layout, with main access directly from any track on the ladder, but sometimes physical reality gets into the model RR room. The trade off of the "unidirectional" yard has paid off in longer tracks and works well. BTW, the quotes around "east" and "west" are because the yard actually runs north and south on the layout. What you refer to as west is actually north. When looking at the control panel you are facing east, but that's another story for another time. The diagram above has been rotated -90 degrees for this discussion. Now you're really confused

Track 8 is a runaround and provides access to the engine facility and aux yard. I have also found the short track 7 is a great place for the yard switcher to stand by. Easy access to either yard end and it keeps 7 and 8 clear of any random spotted cars. The track 7 and 8 combo provides an easy way for the switcher to pull a single car and get behind it, such as a caboose or coal hopper headed for the coal tower. Originally I had two switchers stationed at the lead ends, but since I operate alone and can only drive one at a time, the "yardmaster" has cut back on switch engine expenses and returned the savings to management.

Charlie

Hand signals

In the pre radio days I recall often seeing crews relaying signals around curves, or sometimes up on top of cars. They also used their time tables to help the visibility over long distances. Some of the ATSF caboose fleet had signaling discs mounted on the cupolas. The were more men on a crew in those days and they had finely tuned skills much like a soccer team. They could work very well with just visual or even only whistle contact....DaveB

Hand Signals

Worked with one old head who always carried an old rag, those were his "Mopac gloves". That bit of white from that rag or a switch list sure helped in seeing hand signals from further distances when working in the yard.

Work Rules

Like Dave said, the road switcher would be expected to put their cars away in the track designated by the Yardmaster. In larger yards, where there are switch engine jobs on duty for the purpose of switching cars in the yard, they are the crews that would do all the switching of cars within the yard. In small yards where there are not any switch engine crews assigned to that yard, and most likely no yardmaster either, the road switcher crew would be allowed to switch their own cars, since there may not be any other crews available to do the work.

You switch with "what you

You switch with "what you have". It's not like you can pick the engine up and turn it around easily (although there were terminals where I did "get the engine turned properly" for the work we had to do).
If the engine is "headed the right way", it makes the job easier.

The rule books generally say that when an engine is not headed in the right direction, no movement will be made until the conductor has an understanding with his crew.

These days, crews will work with radios.
In some places (if the engine is oriented correctly), the conductor will use "go ahead" and "back up".
If the engine is "facing wrong", the conductor might use "go east" and "go west" (or go north and go south).
I even remember one situation where the conductor used "come to me" and "go away from me".

Insofar as road crews and yard crews are concerned...

On the larger (unionized) railroads (in times past, which were my times), if the yard was a major (or otherwise significant) one, with yard crews on duty, switching came under the duties of the yard crews by union agreements. A road crew would not switch its own cars, because the yard crew might object that the road crew was "taking their work" and might put a time slip in on 'em.

So an incoming road crew (or even a traveling switcher crew) would probably pull in on an "arrival" or "arrival/departure" track, drop the train, and take the engines to the enginehouse area.

Then, a yard crew would come in and start "working the train".

Today, things are different, particularly on the non-unionized lines.
In that case, the crew will probably do whatever it's instructed to do by the yardmaster or dispatcher.

Times have changed!

Yarding

Correct, and there are intermediate steps in the process.

The road train arrives in the yard.

The clerks have to get a list of the inbound train and the yardmaster has to generate a switch list.

If its a yard big enough to have "arrival/departure" tracks it probably has carmen on duty.  The carmen would blue flag the inbound train, inspect the train, make any running repairs in the train yard, change brake shoes, then bleed off the air.

If its not a big enough yard to have AD tracks, then the switch crew would bleed off the inbound train and make a cursory inspection (but no repairs).

After the train is bled off and then switch list is made, then the yard engine can begin switching.

Bleeding off the air

Mr. Husman makes an important point.  If a train is going to be completely broken up and switched, the air will be bled off first.  This is done by a carman walking the train and pushing the release valve rod on each car.  (It's generally under the center of boxcars, flats, gons, and reefers, and within the end cage of one end of hoppers.)  Walking a train and inspecting it as you go takes time, up to a minute a car.  So it's usually an hour or more before the yard crew can start switching a train, or start shoving it over a hump if it's a hump yard.

Inbound trains that only need a block swapped can get switched with air, but that still takes time.

Scott Chatfield 

Lists

Another aspect are lists.

We are used to the modern world where AE readers generate a train list and computer programs assist generating switch lists in minutes.

This of course assumes you have access to AEI readers and computer car inventory systems.  Smaller railroads or shortlines may not have those amenities.

Back in the pre-computer eras it took a longer.  The yard clerk would have to write down a list of the cars in order as the train pulled into the yard.  Then they would have to match up the waybills to the train list.  From that they would figure out where the cars were going, then write up a switch list, then get the switch list to the crew.  Even if the carmen could have the cars bled off in 30 minutes, they probably wouldn't have a switch list ready to go.