Weird Things Happen when I go to Glendive

I have been training to be an engineer out of Forsyth, which has been challenging.  The challenge is mostly the result of being unfamiliar with the territories handled by Forsyth crews.  Obviously, I will have to be familiar with all of them by the end of the engine program.  Yesterday, I made my first trip to Sheridan, WY, on a coal empty.  Empties are pretty forgiving, so it is not hard to just kind of wing it on a new territory, but the load home this morning was a bit more challenging!

Besides the trips out of Forsyth, I have to make nearly  half of my required trips on territories handled by Glendive crews, all of which are a lot more familiar to me.  Since one of those territories is the line between Glendive and Forsyth, I figured I can save a little money on gas and get a trip in by taking the train home, instead of driving.  So about once a week, I head up to Glendive, usually for the weekend.  I will be doing that again tonight.  I have been up there twice so far, and both times we have had something unusual happen.  The first weekend, we ran through a switch in the Glendive yard, as I talked about in a previous post.

Last weekend, I was called to go home on a vehicle train.  Vehicle trains are kind of weird trains to begin with, because they have very long cars, and all the cars have cushioned drawbars, to help protect the load from excessive in-train forces.  While those drawbars may help protect the load, they make it pretty hard to tell what the train is doing back there.  They also take a lot longer to stretch out and bunch up, since there is all that drawbar slop on top of the normal coupler slack.  All of that leads to some weird train handling and unusual in-train forces.  Those trains would be a lot easier to handle if the railroad did not discourage stretch braking as much.

Overall, the trip was going well, until we got to Miles City.  Just before crossing the Tongue River, the tracks go up a little bit.  They are pretty level across the bridge, and then they descend a little on the other side.  Since there is a permanent 30mph speed restriction in place at Miles City, I was using the dynamic brakes on the locomotives to slow the train from about 50mph.  The speed restriction starts very close to the bridge, at the top of the small hill.  Since the locomotives were doing all the work to slow the train, the slack and cushioning in all the couplers was all bunched up.  As I got to the bridge, and the start of the speed restriction, I started to come out of dynamic braking, since I was down to the proper speed, and no longer needed any more braking.  I thought I was coming out sufficiently slowly to prevent the locomotives from running away from the train and causing a sudden stretch, but I guess that was not true.  Sudden stretches, or run outs, can cause broken knuckles and drawbars, so they are a good thing to avoid!

After the locomotives and first few cars had gotten over the bridge, the engine started beeping and I noticed that the brake pipe pressure at the FRED was 0psi.  That means something had put the train in emergency at or near the rear end.  A few seconds later, the air dumped on the locomotives.  We were in emergency, and we were stopping whether we wanted to or not, and regardless of how many crossings we had occupied!  I actuated the locomotive brakes and tried to manage the in train forces as best I could.  Despite my efforts, we felt the slack bunch up, or run in, very suddenly and violently on the locomotives.  For those of you that have never experienced a run in on a locomotive, the bigger ones sort of feel like being punched in the back of the head by, well, a freight train.  Once we had stopped, I released the brakes to see if the air pressure would recover.  If it did, we would continue on our way, and if not, the Conductor and his trainee would be going for a nice evening stroll.  My engineer suspected that a hose had come apart, as they sometimes do with those cushioned drawbars, and I thought we had broken a knuckle.  I was hoping it was not a knuckle, but for some reason I had the feeling that the train had come apart.

As the air pressure started to come up in the brake pipe, we noticed that the air flow was not dropping very much.  Normally the air flow, measured through the brake valve, drops as the pressure rises.  Despite the air pressure coming up into the 80's on the head end, there was still a leak somewhere.  The Conductor was going for a walk.  He and his trainee got off the locomotive and disappeared to the west.  While they were gone, several pedestrians walked around the front of the train.  I suppose that is better than trying to crawl through or under cars at a blocked crossing.  The police also came by to see what was going on.  After several minutes, we heard from the Conductor.  The train was indeed in two pieces.  He went on though, there were no broken knuckles, the cars had simply come uncoupled somehow.  He had us pull ahead to open up a crossing before we set about fixing the problem though.

Once traffic had cleared at the crossing we opened up, the Conductor instructed us to start the train back.  While waiting on traffic, he had realigned the drawbars.  We put the train together and gave it a good stretch, to make sure it would hold.  Once satisfied that the joint was solid, the Conductor and his trainee started heading back towards the front of the train.  Once they were on board, we continued our journey east, without further incident.  In talking about what happened, there was only one explanation any of us could come up with that made any sense.  My engineer suggested that when I came into Miles City, with the train bunched up, it might have been possible for the uncoupling lever to catch as the drawbar compressed, causing it to lift and release the knuckle.  Then, when I started pulling on the train again, obviously it would have pulled that knuckle open, allowing the train to separate.  He also suggested that the huge run in we felt may have been the rear portion colliding with the front portion as they both went into emergency.  That would also explain why the Conductor found both knuckles closed and the drawbars pushed way off to the sides when he went back.  We will never know for sure what happened, but that is the only explanation that sounds plausible.