Trains with two locomotives......

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Here's a question:

On Amtrak trains which have two locomotives, why do some have the secondary one facing forward, while others have it facing backward?

Also, two locomotives is called "double-heading", right?
It's completely the option of the dispatching yard. The way the locomotive controls are wired, it will run just the same if it is facing forward as if it is facing rearward. The forward/rearward (as in the classic A-B-B-A lashup) was favored during the streamliner era for symmetry, but forward/forward is more practical from the standpoint of keeping the train operable and moving if the "point" locomotive goes bad-order en route.

"Double-heading" was a steam term for operating two locomotives on the same train for much or all of the run, as opposed to a "helper" locomotive which was added only for a short run up a heavy grade. Double-heading required two full locomotive crews as steam locomotives were not able to be fitted with MU (Multiple Unit) controls. Edit To Add: Coordinating the work of the two locomotives was tricky and, in the days before widespread availability of reliable radios, usually required whistle signals.
 
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Here's a question:

On Amtrak trains which have two locomotives, why do some have the secondary one facing forward, while others have it facing backward?

Also, two locomotives is called "double-heading", right?
Sometimes it depends on where the power may be going after said assignment. They might not have time to "spin" the power if the power is running what is called "Elephant Style". Which is where both locomotives face direction of travel. If the power is not running elephant style it's what's know as a "back to back set". Meaning that the power has cabs that can be used easily and the power doesn't have to "spin". The only time power would have to "spin" in this configuration is if the leader has bad cab signals, or a bad radio, etc. A good train that you will see with this is the Auto Train. The train turns quickly the same day and I also believe that there isn't a place where they can "spin" the power for the return trip.

Two locomotives these days could be called double heading sure. But the original practice is as described above.
 
Right now NCDOT Piedmont trains have two engines, one on each end. They are operated this way so that the train doesn't need to be turned at either Raleigh or Charlotte. Also, the train cars are cabled so that the engines are MUed to each other and work in tandem.

Sometime this year one of the engines will be replaced with a Cab Control Unit, which is a locomotive that has no prime mover. It will be used as a platform for the engineer to control train movement. This will still allow the trains to be run without turning at either end.

jb
 
There are also quite a few "purpose built" cab cars around especially on commuter railroads, and out East, we have some old Metroliners turned into cab cars mostly for the Keystones. The de-powered F-40 locomotives (NPCU or Cabbage) wouldn't fit into NYP.
 
Right now NCDOT Piedmont trains have two engines, one on each end. They are operated this way so that the train doesn't need to be turned at either Raleigh or Charlotte. Also, the train cars are cabled so that the engines are MUed to each other and work in tandem.

Sometime this year one of the engines will be replaced with a Cab Control Unit, which is a locomotive that has no prime mover. It will be used as a platform for the engineer to control train movement. This will still allow the trains to be run without turning at either end.

jb
I just saw a Piedmont with only one locomotive while riding the Carolinian about three weeks ago. They seem to generally run with two locomotives, but that is not always the case. There are wyes at both endpoints when they are necessary.
More generally, long-distance Amtrak trains run with both locomotives up front, while shorter-distance trains place one on each end (if there are two locomotives). In addition to being done this way in North Carolina and on some Midwestern trains, commuter railroads sometimes operate this way on longer trains. I know for sure the LIRR sometimes does this, especially on Hamptons/Montauk trains in the Summer.
 
East Bound Empire Builder arrived Spokane with only one locomotive. Entering the Yards, we passed a sole Amtrak locomotive on a siding with the Engineer standing in the doorway. Leaving Spokane, EB had 2 locomotives, both traveling forward. I assume that the sole locomotive simply coupled onto the front of the one that took EB from Seattle.

Am I correct in my thinking?
 
East Bound Empire Builder arrived Spokane with only one locomotive. Entering the Yards, we passed a sole Amtrak locomotive on a siding with the Engineer standing in the doorway. Leaving Spokane, EB had 2 locomotives, both traveling forward. I assume that the sole locomotive simply coupled onto the front of the one that took EB from Seattle.

Am I correct in my thinking?
You probably saw the #8 Portland Section P-42 added since 7/27/8/28 splits/switches in Spokane.
 
Unless the F59s load like a drunk pig (or a P42), those top and tailed (yea, UK term, but whatever) Piedmonts must have been going like bats out of...a very hot place pulling away from stations!
 
I have ridden aboard the CZ in winter when the two locomotives were running elephant style and it came in very handy. The engineer had to reverse their possitions at the top of Soldier Summit in a raging snowstorm, because the lead locomotive's "dead man's throtte" was misbehaving.

The sole engineer in the lead unit had to radio the conductor to come forward and sit in the second unit while he reversed their positions through the crossovers on the double track main at the summit. Apparently, it was not considered safe to leave one unit unoccupied for any extended period of time while moving the second unit.
 
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Right now NCDOT Piedmont trains have two engines, one on each end. They are operated this way so that the train doesn't need to be turned at either Raleigh or Charlotte. Also, the train cars are cabled so that the engines are MUed to each other and work in tandem.

Sometime this year one of the engines will be replaced with a Cab Control Unit, which is a locomotive that has no prime mover. It will be used as a platform for the engineer to control train movement. This will still allow the trains to be run without turning at either end.

jb
I just saw a Piedmont with only one locomotive while riding the Carolinian about three weeks ago. They seem to generally run with two locomotives, but that is not always the case. There are wyes at both endpoints when they are necessary.
I saw a Piedmont yesterday with two locos. First time I saw that. Ugly. The NC locomotive (MRC?) looks good, the restored heritage cars look good, the Amtrak Genesis looks good. But lashed up all together, it's one ugly looking consist with NO symmetry or continuity in design.

Thankfully, the interior is really nice, and a joy to ride it. Just close your eyes until you're onboard. :D
 
NC was supposed to convert some (5) F59PH into cab cars. Did that happen? If that took place, it could look like a locomotive at each end, but actually be push-pull.
They are converting two or three. I haven't seen any of them yet.

When the CCUs are placed in service, it'll probably dictate a change in the operation of the Piedmonts. In the beginning, the Piedmonts ran with one engine. There were frequent engine failures so a protect engine was placed at Charlotte. The trains continued to run with one engine. Of course this required each train to be turned at Charlotte. Then about a year and a half ago, the installation of double track in places where there was single track between Charlotte and Greensboro, got underway. Train delays ensued. It became difficult for the trains to get to Charlotte with enough time to turn the train without delaying the northbound departure. The solution was to put an engine on both ends. At that time the protect engines were removed.

So when the CCUs are placed in service, I would expect the protect engines to be put back in Charlotte. If I had my way, they'd put one in Greensboro, too.

jb
 
Many times, when two locomotives are provided, its not about the power but about the redundancy.

Diesel locomotives do have a certain failure rate and that increases with age. A broken down train is a nuisance to those on it, but also to other trains, including freights, using the same line.

One way to artificially increase the MTBF of a diesel plant is to artificially cap its power by say ten percent. This can be done by mechanically throttling the fuel intake. The military does this a lot as one thing they can't have is vehicles breaking down in critical situations.

But also taking the demands of HEP into account, capping power can impact a train's performance. So sometimes two locomotives running at partial load make more sense than one running at full load.
 
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This inability to run a train relatively reliably over a thousand miles using one single diesel locomotive seems to be peculiar to the US though. ;) Might have something to do with undercapitalized operations causing a failure to maintain equipment adequately.
 
Here's a question:

On Amtrak trains which have two locomotives, why do some have the secondary one facing forward, while others have it facing backward?

Also, two locomotives is called "double-heading", right?
It's completely the option of the dispatching yard. The way the locomotive controls are wired, it will run just the same if it is facing forward as if it is facing rearward. The forward/rearward (as in the classic A-B-B-A lashup) was favored during the streamliner era for symmetry, but forward/forward is more practical from the standpoint of keeping the train operable and moving if the "point" locomotive goes bad-order en route.

"Double-heading" was a steam term for operating two locomotives on the same train for much or all of the run, as opposed to a "helper" locomotive which was added only for a short run up a heavy grade. Double-heading required two full locomotive crews as steam locomotives were not able to be fitted with MU (Multiple Unit) controls. Edit To Add: Coordinating the work of the two locomotives was tricky and, in the days before widespread availability of reliable radios, usually required whistle signals.

Lookinglasstie,

Ehbowen, Acela150 and Dutchrailnut have basically hit the nail on the head (although Amtrak refers to MU'd engines as Double Headers and multiple units with more than one crews as Helpers) with one exception. Trains that are programmed to operate with more than one locomotive have an operating plan that instructs the facilities on how the power is to be arranged.It is not completely the option of the dispatching yard as they may not know what will occur (as explained by Acela150), Additionally, there are guidelines on when trains with more than one unit may use the unit for propulsion vs having isolated or providing HEP.

This inability to run a train relatively reliably over a thousand miles using one single diesel locomotive seems to be peculiar to the US though. ;) Might have something to do with undercapitalized operations causing a failure to maintain equipment adequately.
I'm not sure if you've been paying attention, but what you described is at a critical point. Failures (with even multiple units) are steadily increasing (along with the associated delays), which is straining the rest of the fleet. Something really needs to be done. CSX has sidelined a ton of power. They find the route with the lowest speeds (such as the Adirondack and Auto Train) and add them as slugs/helpers.
 
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