Speaking Signaleze

by Denis M. Larrick

From Modeltec, February 1991

(Ed: This article has been updated using BNSF Aspects and Signals)

Who among us has not at one time felt, if not totally ignorant, then at least selectively stupid when standing alongside the "big kids" tracks, attempting to decode the intentions of the signal department? Now, this is not a guide to the twenty zillion variations peculiar to individual railroads, but a simple list of the most common standard signals, providing that authentic aspects aren't beyond the average miniature coal-slinger and, in fact, could be quite practical and colorful along our tiny trials. There are only two simple rules to remember.

1. Unless a signal is all red (meaning STOP), the color red is just a place keeper, saying, "don't look at me, stupid, look at the other lights!"
2. American signals show speed, not routing. You will find out where you are going when you get there! If a mast has more than one head, the top head permits you normal rulebook speed. The second head restricts you to travelling "medium" speed (30 mph) ... may times (but not always) a diverging route through a switch. if a third head is used, it will indicate a slow speed (15 mph) route, such as a tight curve through a wye, a string of switches coming up, etc.

Not too tough, eh? Now let's jus pretend we're out on the high iron ...

Ah, a clear track. "Proceed." This means at least the next tow blocks are clearn. (No "Smokies," either!)		or
"Approach" is saying that the next signal will probably be "stop", so slow down and be ready!		or		or
"Stop!" (Enough said?)		or		or
"Approach approach?", Close! once in a blue moon, if the blocks are exceptionally short or speeds are high, "Advance Approach" will give you two blocks warning before a stop.		or

So, traveling down the tracks, we might see:

then

then

then

OK, so far, so good. Suppose we just fantasize for a moment that the turkey in the tower is going to put us in "the hole" so a hotshot can fly by. To go through the diverging route of the switch we will need a "medium" speed indication, right? How about...

Shall we call it "Diverging Clear?" We shall, and so do the railroads! 30 mph and at least two clear blocks

or

But what if the next signal is "Stop?"

Yep, you guessed it! "Diverging Approach" ... "medium speed" (now) approaching stop (next signal).

or

But wait a minute! They gave us some warning before a redboard, so why not some warning before a medium speed route, too? (Gotta start dumping the air in advance, you know.)

Approach over medium. What do they call it? Well, "Approach Medium," of course! Normal speed (now) approaching medium speed (next signal) means to start slowing down to 30 mph because that next ol' signal is gonna do it to you anyway.

or

or

And if anyone cares, once in awhile you might see;

"Approach Limited" You've got the smarts to figure this out by now, eh?

So chugging down the line now, we might see:

then

then

then