No. But you need to make sure you set each unit in the consist in the correct direction.
Or if you’re filling out maintenance info on a locomotive, you need to be able to indicate “problem on the right front corner” properly…
As do cabless “B” units, and symmetrical and double-end units like GG-1s, AEM-7s, and little centre-cab switchers…
Actually no, see my post above. I’m sure there are exceptions, and the latest modern stuff may be different, I don’t keep up with that. But take a look at the link I posted.
Since the following units control circuits are actually powered by the lead unit, the pin assignments in the cables automatically configure the direction. But, you do have to set the forward/reverse lever of the following units to neutral and remove the handle, which then disables the control stand and allows the lead unit to control the following units.
And, if you wish to change the lead unit to the one on the other end (ABBA for example), you must change the current lead unit into a trailing unit (remove the forward/reverse lever and turn off a few other things) and then set the unit up on the other end as the lead unit by reinstalling the forward/reverse handle.
Sheldon
Keep in mind that on many railroads, further designation of components goes from the effective “F” end (it is called something different on cars, but has the same effect). If specifying a bad axlebox, or traction motor, or wheel on an axle, it will be with reference to the nominal ‘specified end’ with no need for further consideration of which way the equipment might be facing, or whether it’s part of an MU-set consist.
One thing re m.u.ing engines…there were a very few diesels built with m.u. connections only on one end. I know Soo Line’s ‘covered wagon’ A-units (like an F7A) only had m.u. connections at the back, so they always had to be at one end or the other in a consist, facing away from the other engines (GPs, FAs, etc.) in between them.
Also, not sure of the railroad(s), but I seem to recall some very early diesel switchers were purchased to run together back-to-back in pairs, and were therefore ordered to only have m.u. connections in the rear.
(p.s. speaking of Soo Line, seems to me their Baldwin AS-16s didn’t have any m.u. connections at all?)
Hate to correct a fellow Penn Stater, but you are wrong. RS3’s were built for short, long or bi-directional operation (two sets of controls, one on each side of the cab). The railroad would designate whichever end the controls faced as the front and made an arbitrary decision in the case of bi-directional units.
As noted, ICC regulations required a “F” be stenciled near the end of whichever hood was designated as front. This was to aid in accident investigations - early electric and diesel units were box cabs with no obvious front end, so one would be assigned
Boxcab
Note the lettering saying “No 1” which was an early way of designating the front end, “No 2” would be the rear end. Note there is also a “F” stenciled on the side of the cab
It was also common to paint locomotives asymmetrically indicating to those who knew which end was the “front”. CPR went to the trouble of repainting hood diesels that were permanently “turned around” to run the “other way”. The FM Trainmasters were so treated for example.
I think it quite likely that conservative types like train engineers were more comfortable driving the early hood diesels long hood forward because the long end of a locomotive had been the front for so long. Certainly long forward was a fairly short lived fashion.
I wonder if SP ever ran long hood forward given their history. I also wonder why it wasn’t really obvious that running short hood forward was the way to go. Who enjoys diesel exhaust blown in your face?
But… That’s what I said. The F determines the “front,” per regulations. How they arrived at that decision is immaterial.
The Union Railroad loves running their MP15s the “no hood” direction, for visibility. They’re paired up long hood to long hood, so that they have the no hood view available in both directions. They’re equipped with dual controls too. But, there’s that little F on the long hood. They treat and operate them like the no hood end is the front. But, it isn’t “really” the front.
AAR_Locomotive Designation by Edmund, on Flickr
AAR_Locomotive Designation_0001 by Edmund, on Flickr
Regards, Ed
One more reason to designate the front or No.1 end of an other than steam locomotive, is when traction motors must be cut out, to isolate or eliminate a problem with them. Traction motors are usually set up to be cut out in pairs, and to count them, No.1 is always nearest the “F”. Most units had them arranged in pairs and, they were cut out, one on each truck as in 1, 3 or 2, 4, or on a C-C unit, 1,4 and 2, 5, and 3, 6.
Probably so, although I don’t think rail engineers were consulted by the manufacturers when the first diesel switchers were being built. I suspect it was just what was common. The first passenger diesels were based on electric boxcabs with the engineer up front, so that became the norm (like with E-units). Steam switchers had the boiler in front of the cab, so the early diesel switchers had the long hood with the engine in front of the cab too.
Most railroads that ran long-hood forward with GPs or SDs switched to the short hood when the low hood was brought in around 1960. I guess the last locomotives designed to be long-hood forward were EMD’s MP-15s of the 1970s. (A few railroads bought engines set up long-hood forward after that, but these were engines virtually all other railroads operated short-hood forward.)
Which way round was the second locomotive in a pair if both were long hood forward?
I have two such Atlas Trainmasters and wondered if they would be coupled elephant style or back to back like a short hood pair normally would. The one photo I found is of three FM H16 44 which shows one painted for short hood in the lead cab forward followed by too long hoods elephant style cabs at the back.
The initial reason for the long hood forward was that the first road switchers were modified end cab designs. The long hood was forward on them, so it was carried over on the first road switchers. Some railroads kept that practice when ordering road switchers in later years when orientation became an option. Others didn’t.
On conventional locomotive consists, the engine set up to lead controls the direction of the entire consist through it’s reverser. All other unit’s reversers are removed and stowed.
When setting up a distributed power consist(s), the direction of the remote lead engine must be known and entered into the DP contols. The choices are "Same as Lead: or “Opposote of Lead.” It’s happened that the DPs were set up wrong and the DP tried to pull the train back.
Jeff
The cabs on both units would be towards the middle if both were set up to run long hood forward and the long hoods were pointing in opposite directions. This is eliminate turning at the terminal point. This is not a hard, fast rule though. If there was a wye or turning loop at the end of the run, they could be run “elephant style”, nose to tail like Burlington used to do with their E units in the latter days, or Amtrak does today. Best answer: Whichever way they came off the ready track!
There are many variables that could affect building a locomotive consist, so there is no hard, fast, chiseled in stone rule, other than owner’s preference. Diesel-ELECTRIC locomotives are big, dumb brutes that don’t know or-care if they’re coming or going. Acommodation is usually only made for the people inside.
At the time these Trainmasters were in use by the CPR long hood forward there were turntables everywhere in CP’s system because steam was very much in use. The particular division where most of the FM motive power was in use, Southern BC, the dieselization happened early on so turntables would have been readily available to turn these large locomotives if need be. Lots of wyes also.
Some consists are built with specific engine orientations, some are just mine run. For example, we used to build UPS trains with the first two engines in the consist pointed forwards, then the rest however they fell. That way if the first unit failed we would still have a engine facing forward to use as a leader. A two unit set that we knew was going to turn would be built back to back if we could.
Yard engines are faced so the engineer is on the lead side, so he can see the ground crew on the lead.
At N Platte, NE on the UP, all the consists at the shop are built with the lead unit facing east. To get to the westward side of the yard, the power goes over the “sheep jump” a running track for power that goes up and over the main tracks, turning the power facing west.
Which is why I said all electric and diesel-electric engines have been required to have a designated front for at least a century.