Direction of Diesel Consists

It is so they do not have to turn the locomotives when going the other way.

I dunno, I see a lot of BNSF trains rolling through the Chicago suburbs with all the units facing the same direction.

I don't think the railroads are that fussy anymore.

I think its just more the direction the locomotives are pointing when the consist is assembled.  Heck, in the old days I would see the California Zephyr go by with 3 or 4 E-units running "elephant style" more often than not.

Another thing to consider, back in the early days of cab diesels, they were intended to be run more or less as matched sets and the noses didn't have MU receptacles installed.

Rusty

Santa Fe late in the private passenger era did run F units AABB.  Reason:  In case first F unit cab goes south, the next unit could take lead!

See thats what I am thinking....and also what Rusty said i.e. "Elephant Style"...yet all the model train ads show them in opposite directions.

E's and F's look better back to back, that's why the ads show them that way.  That's the way I run 'em.

Rusty

The other reason the carbody units all ran tail to tail, is because there was a door in the rear of all of those units. While underway, an engineer or fireman could walk through his engine into the other engine through those doors without stopping the train.

With hood units, B&O employed an interesting procedure on certain priority trains in which all units were positioned facing the direction of travel. In the event of trouble with the lead unit, it would be set off at the first available opportunity and the first trailing unit, now in the lead, would already be facing the proper direction minimizing delay. This practice countinued well into the Chessie era.

Bob  

Looking at the older F style units,realize that operating these units with the rear facing forward would be possible,but awkward as can be.You would have a bad field of vision with an F style locomotive.

  Now getting onto say the GP style of locomotive you have a better field of vision and can operate that locomotive fairly easy long hood,and even some railroads,Southern for example,had controls that faced long hood on the right side and the control stand was formatted to operate that way.It allowed railroads without the availability of a wye or turntable the option to have units facing which ever way.

  Now on today's locomotives a lot of your trains say on the NS,that run from Chicago to Roanoke ,they most likely will never take the head end power off,and so it doesn't really matter other than the lead unit facing with the F end forward,how the other units in the consist are turned.They are just being used as needed power and dynamic braking.

 Short hood forward is the desired way of operating on long haul trains.FRA really prefers this also.I'm not certain if they actually have a law out about it right now,but it has been a topic of debate to make it law.It's just safer when possible to operate with short hood forward.

  But like on the road switcher job I work,it doesn't really matter because I'm usually switching in a yard or an industry,and really never travel more than 30 miles one way.I'm also usually on a SD40-2 or a GP-38,and the one GP-38 we've had lately has the controls on the right side facing long hood end.

 One other situation that I can explain.Our 233 piggy back train has it's rear trailing units,set up for when they drop them off in Columbus,Ohio at the Rickenbacker intermodal  facility,to be used  on the 236 going back east,with the 233 rear unit facing short hood .So that consist is  purposely built in that manner .

I think SOU, N&W, and NS ran long hood foreward so there was more engine between the cab and the engine front.  Mute point once the "safety cab" became standard.

Southern and NS definitely ran long hood forward well into the second generation diesels.   They also bought all "high short hood" units.    The long hood was the front.

As for AAs elephant style, all the comments above about being able to use them in both directions more readily apply. 

But also most if not all A units from all mfgs did not come with MU connections on the front.   These were generally added at the first major rebuild when they were about 15 years old.   At the point the RRs realized how not having the MU was limiting flexibility and efficiency.   So basically a brand new AA set would have to run back to back or have two crews.   No RR wanted to run them with two crews.   

In today's world, the RRs assemble consists based on needed HP (as they have always done) and also to get one unit facing in the dirrection of travel.   It is probably very convenient if they have a units facing in opposite directions at each end of the consist.   That way the whole set can run either direction on its next assignment without being disconnected.    Again it is more flexible and efficient.   

Early on the RRs or the hostlers seemed to think nice matched consists with As facing out were important.    But they all learning that the engines are just building blocks to a consist (which they call a locomotive) that has the HP they want.

Railroads like the CB&Q that often ran 'elephant style' on mainline freight or passenger trains would normally have had some way to turn the engines as a group, like a wye. It wasn't uncommon to see a couple of the Q's E-units pulling a passenger train, but they were always facing forwards. You never saw them running backwards with their noses facing the cars. St.Paul Union Depot is built on one leg of a wye, so CB&Q trains from Chicago could easily have their consist reversed in the wye by the depot.

When Northern Pacific dieselized the North Coast Limited, they originally used A-B-B sets of F-units. However they found that backing on to the train in St.Paul (and I think Seattle?) was difficult, because the engineer was on the outside of the curve and had no way to see what was going on. By changing to A-B-A sets, the engineer could go to the rear A unit and run the consist back to couple to the train, then go back to the lead unit to run the train.

Another diesel was often needed thru the Rockies, so in the western part of the NP they'd add another A unit, so you'd often see A-A-B-A engine consists.

I wouldn't say never.  I'd see Q E's running back to back as pairs, back to front to back or back to back to front in three unit sets and almost any combination with four unit sets.  It's just that elepant style for all units in a consist was more prevalent.

With the Q particularly out of Chicago, the E's could be in the commuter pool one day and pulling a Zephyr the next.  (I remember even seeing an E5 on a dinky once in a great while.)  This could explain more on why the locomoitves were oriented the way they were.  The Zephyr pit was south of Union Station, while the closest Q turntable was in Clyde Yard in Cicero, 6-7 miles away.   Anything being wye'd would have to be done a little further south of the entrance to the CUS yard complex.

Rusty

Yeah I wouldn't say never either...  It was a mixed bag on the Q.

http://www.burlingtonroute.com/gallery/displayimage.php?album=1&pid=647#top_display_media

http://www.burlingtonroute.com/gallery/displayimage.php?album=1&pid=653#top_display_media

As Rusty noted, the railroads took their earliest deliveries of F units as matched sets.  It was not unusual for an A-B or an A-B-A combination to be attached by drawbars rather than couplers.  Being connected by a drawbar prevented any ability to operate the set in a configuration other than how it was delivered.  The lack of operational flexibility is one reason railroads soon began to remove the drawbars and replace them with couplers.  Rich notes this in a related thread on the Real Trains site.

I've read that one reason railroads tended to order the earliest sets with the drawbars was that they were considered "one" locomotive.  That is why if you look at early photos, you'll see, for example, units numbered 150-A, 150-B and 150-C.  The union agreements at the time specified a separate engine crew for each individual locomotive on a train.  If the diesel engines all carried the same number, they were considered one locomotive according to the union agreement and thus, only required one engine crew.

Curt 

Actually I would say never.

My point was that the Q would often run two or three E-units all facing forward on a train, but never ran a passenger train with all the units facing backwards. If two E-units were both facing forward Elephant-style pulling the Zephyr from Chicago to the Twin Cities, the units were turned (probably on the wye west of the Minneapolis GN station) so that they were facing the other direction when they pulled the next train back to Chicago, so they'd both still be going forward. They didn't hook the cars up the the nose of the lead engine and have the back of the other engine leading the way back to Chicago.

I agree the CB&Q often ran E and F units with some facing forward and some facing back, but the lead unit would be facing forward.

Although by no means very well informed about real trains and their standard operating procedures, I can't imagine a train with multiple cab units and the lead one is backwards.  That doesn't make a lot of sense for several reasons.  What self respecting crew would let that roll out of the yard that way?

Ahh ok Stix I misunderstood you....