he WAZU was our problem home layout. The owner wanted it to be modern high-speed rail service between Seattle and Portland – big trains running fast on open tracks. But whenever we did it, we quickly ended up with snarls on the railroad and the radios making everyone’s ears bleed. Of course, then the crews were having to shout at each other to be heard over the radio noise. Not good. And the owner did not want to install phones.
We’ve done simple mother-may-I. Then we tried warrants. Each time we got some combination of booming radios and delayed trains. I tried to suggest dropping trains or slowing the clock but the owner would have none of it. So then I came up with Dis-Fasting (I named it only after it worked so well for us).
Things I noticed:
Something else that hit me. I realized that when I dispatch, I’m looking somewhat into the future. Before I issue an order, I have to scan the board and anticipate where every train will be. This crystal-balling adds a little more time to the effort. At this sort of speed, I need to issue an immediate order, not for waiting for another train and following under restricted speed or anything else. The crews couldn’t remember it and writing it was too slow.
So our new primary assumption is that the line is ABS blocked. Trains are protected from the rear by block signals (head-ons are still the responsibility and embarrassment of the dispatcher). Once a train follows another, I am guaranteed that they will watch out and stop with adequate distance without me mothering them along.
Really, when you look at what dispatchers do on a single track main, it’s pretty much running trains to passing sidings to meet others, moving them efficiently. Once they meet, they are onto their next meet. In warrants, that would be a “proceed” checkbox, a “main/siding” checkbox, and a “wait until” checkbox. That’s the basis of single track main operations.
So now, in Dis-Fasting (which is pure verbal – no writing), there are two things I’ll tell the crew 99% of the time when they wish authority to proceed.
Seems simple and obvious, but it’s subtly different from both mother-may-I and warrants. For one thing, once a train arrives and calls me, I know he’s in. He’s going to want permission to proceed. If he can, I give it. If he can’t, I tell him who he is waiting for. If the latter is true, he has a vested interest in reporting the train in as soon as it’s there, and when he does, I will give him an instant “proceed” order. This puts the responsibility to keeping track of trains to the crews. Even better, I’m not trying to figure out where everyone is going to be in the next 10-20 minutes. I can see on my board right now where everyone is at and move him (with a quick instruction) to the next pass. And since crews are expecting only two formatted commands, the transmissions and replies are quick.
If a switch crew is working on the main, I’ll order them to flag. Imaginary flagmen and block signals ensure that trains don’t crash (except for the aforementioned head-ons).
Yes, I enjoy running (and dispatching) on all manner of layouts, from mother to warrants to TT&TO to CTC. I know people who allow crews to toggle the signals between passing sidings to “own the block” (essentially English tokens). Every railroad has a dispatching method that is best for it. And for heavy traffic at high speeds with a desire for limited radio use, dis-fasting is the best method I’ve discovered.