When two or more locomotives are running in a consist, why is one running in reverse? I have been researching this for a while and cannot find the answer.
Thanks in advance,
Mike
Whether all the units in a diesel consist face the same way or different ways doesn’t really matter. The practice of having a cab at both extreme ends allows the entire consist to return to its starting point without having to run it around a wye or balloon loop.
Actually, that’s a problem I don’t have. All of my diesel-hydraulics are center-cab designs.
Chuck (Modeling Central Japan in September, 1964)
Because trains run in both directions. So if a train runs from Kansas City to Chicago, when it gets to chicago, they can just fuel it, a new engineer gets on the other end and its ready to run atrain from Chicago to Kansas City.
If there aren’t engines facing both ways then they have to turn the engines, turn a engine or cut a “wrong” facing engine and add a “right” facing engine. While most of these things can be done at a typical large terminal, they often can’t at a smaller terminal and in any case cost time and money and people to fiddle with the engines. By building a double ended set, its cheaper and more versitile.
Dave nailed it. It’s so they don’t have to turn the locos to run it in the other direction. Which way the loco is facing makes no difference in its performance… just the visibilty that the engineer has.
But when they have two on the front and one is facing forwards and one is backwards, why is that?
Because as mentioned when the get to their destination and are coming back to where they originally left from the locomotive in the back will now be the one in the front. Get it the engines will generally hook up to a completely new set of cars and head off in the opposite direction.
In the event that the lead engine fails the consist already has another forward facing cab, thus eliminating the inconvenience of needing to find/turn an engine in the proper direction.
Thanks for helping understand this. I really appreciate it.
Mike
This goes back to the first A-B-B-A demonstrator set, EMD 103 from late 1939. (With FT 103 the A-B sets were connected by drawbars, they could run as two A-B sets or back to back as one A-B-B-A set.)By running back to back you eliminate the need to turn the engines on a wye or turntable. It was easy to maintain those arrangements because most railroads bought three or four unit sets of F units and gave them all the same locomotive number (usually with a letter designation to tell the individual units apart) and kept them together as if they were really one engine.
Keep in mind that when more than 2 engines are used, the preference is for the two outside ones to be facing outward, but it doesn’t matter that much which way the engine or engines in the middle face. Plus remember that “stuff” happens, so engines might need to be shuffled around and replaced and not be set the way you’d like them to be. Earlier this week I saw a CP mainline train with all three engines facing forward for example. Amtrak seems to often run with all engines pointing forwards too.
You may be equating locomotives to autos in which there is a definite advantage to driving in drive as opposed to reverse. locomotives are totaly bi-directional. There is a motor on each axle that drives a gear on the wheel set. The motor can run equally in either direction as can the locomotive. To further explain the answers above real railroads don’t run on loops they run in straight lines. When they get to the end they go back the way the came.