Thursday, January 7, 2016

Flying Switch

Robert Michalka -> Grand Trunk Western Historical Society
Robert's comment:
Flying switch gone wrong: GTW 6049 (ex DT&SL 49) made a flying switch to get around a car of plastic pellets and was trapped in the siding when the car stopped short. James River paper mill, Rochester, Michigan, September, 1989.
Like poling cars, doing a flying switch is another railroad practice that is now generally outlawed. Unlike poling, which is not allowed by FRA rules, it is a railroad rule that prohibits doing a flying switch. Most railroads have this rule. But Matt Cox commented on the posting that "We do it once in a while on the glc." The reason the FRA explicitly outlawed poling is because it impacts how locomotives and freight cars are built. Specifically, they no longer need to include four poling pockets when they design and manufacture new equipment.

Before discussing the photo, I'm going to describe my understanding of what a flying switch is. Below is a diagram of a "facing switch." (The L is the locomotive and the C is a freight car.) It is no problem to spot (leave) a freight car on the siding: throw the turnout to the siding, drive forward so that the car is where you want it on the siding, uncouple the car, backup the locomotive so that it is back out on the main, throw the turnout back to the main and proceed on your way.


The following is a diagram of a "trailing switch." Notice that the locomotive, not the car, is closest to the turnout.


(Update: when I originally wrote this, I had assumed a different crew member does the different functions. The video at the end of this posting demonstrates that one person does the functions but sometimes needs to run pretty fast. I have rewritten the text to assume one, instead of three, crewman doing the ground work.)

The engineer starts far enough away from the turnout so that there is room to:
  • get the car rolling pretty fast,
  • slow down a little so that there is slack in the coupler,
  • allow the car to be uncoupled,
  • go really fast to open up a gap between the car and the locomotive.
The gap has to be big enough to allow the turnout to be thrown after the locomotive has passed the points but before the car reaches the points. Note that "pretty fast" means that the car is going fast enough that it will coast all the way onto the siding. But it can't be going so fast that a crew member can't jump on the cars and apply the hand brakes to stop it quickly. The picture shows what happens if the car is not going fast enough to coast clear of the mainline. The crew gets out a rope or chain to pull the car past the fouling point.

Once the car is on the siding, the turnout can be aligned to the main so that the locomotive can backup, then aligned back to the siding so that the locomotive can couple to the car and do an accurate placement of the car.

On Facebook, Doug Hefty pointed out that you can set off this way, but not pick up. Since many sidings are parallel to the mainline, pick up may explain why they did poling.

In a posting, Bubba Six comments: "In 1988, I recall seeing the N&W fly switching cars behind the Cargil elevator. I was amazed."

Update: I found an explanation by a real engineer, and I learned that I left out two important preliminary steps:

  • test the turnout to make sure it works easily and correctly
  • check the handbrake on the car to make sure it will stop the car

His explanation:
A drop, also known as a flying switch or running switch, is performed as follows; you place the members of your crew in position to perform the task. Then, you test the switch you will use to assure it will line easily and also test the hand brake on the car to assure it will work properly and stop the car as designed. Once said tests are performed, you being by starting to accelerate the locomotive and car or cars you wish to drop. The Engineer will then reduce (not shut down) the throttle a bit, possibly apply some locomotive brakes to slightly retard the speed enough to allow the slack between the engine and car run in enough to operate the pin lifter to uncouple the car. After receiving the sign from the crewmember pulling the pin, the Engineer then accelerates rapidly away from the car. Once clear of the switch to be used, a crewmember at that switch will quickly line it for the following car or cars to roll into that track. When said car or cars roll completely into the clear, the hand brake is operated on the car to stop it. The engine is then brought back out of where it was ducked into the clear and into the track where the car went, coupled on and you then go about your business.
Sometimes this works with no problem, other times it does not. When it doesn't is being saved for a "When Things Go Haywire" column of the future. This particular episode went well, only a little too well. Nobody tested the hand brake on the car and when the time came to stop it, the car would not stop, the hand brake did not work. Oh oh.
My buddy (who was the Conductor this day) was riding the car and suddenly learned of his dilemma. The car was rolling at a decent clip but not too fast, right towards the industry they where switching. He could not stop the car and while the door on the end he was going to shove the car into the plant was open, the one on the other end was closed. One of the Foremen at the plant, who was a neighbor and friend of this guy's was observing the situation and realized his buddy was in serious trouble. He ran to the other end of the plant and depressed the button to open the door at that end. Fortunately for my buddy, this guy's quick thinking saved the railroad considerable money in a new door and an investigation on the crew involved.
The door rolled up, the car rolled through the now open doorway just clearing the now barely opened door and out the other end of the plant. This Foreman and my buddy said they were both throwing debris like scrap lumber and the like onto the rail to slow and stop the car. When it hit the bumper post at the end of the track, it was rolling very slowly and did no real damage.
A video  showing a flying switch at 3:15-5:20. At 4:10 you can tell the engineer backed off the throttle to create slack, the rider pulling the pin and then waving the engineer to gun it and get out of the way, and then he jumps off to move the turnout. Fortunately, that lone crewman didn't have to run to catch the car and apply the handbrakes because they let a cut of cars stop it. Evidently riding in front of the boxcar has also become prohibited: "Jack Fuller I cannot believe that a railroader of today would ride on the crossover platform!"

Another video of a flying switch. I assume that "riding on the crossover platform" is when they are riding in the middle of the end of a box car. A guy is doing that in this video as well. Why did they use the horn for one crossing, but not the first one? The flying switch starts at 7:35. I learned the uncoupling, throwing of the turnout, and applying the handbrake can be done by just one person. I found the video on Facebook and they provided a date of May 16, 1991.

The Wabash Central does a variant of a "flying switch." They come to a complete stop, then they let the hopper coast through the turnout.

1 comment:

  1. Dropping a car past the engine is not that bold a move. My dad who switched for four different roads from 42 to 69 ( the last twenty for the RI) talked about the flying dutchman. You pulled away from the car on the fly and then reversed the engine against the movement of the car into the clear then lined the switch back to let the car by. It was outlawed.