Okay so let’s forget about the dozen or two typically used aspects/rules with most RRs in North America. Who can tell us of an aspect and/or rule that is truly unique and rare. Maybe there is a RR using purple/blue/orange (for exmaple) to indicate a rule. Maybe there is a RR using standard colors in a rare aspect to indicate a very unique rule…for example buffalo crossing. Sounds foolish I know, but someone out there knows of a signal whose purpose and/or indication is truly a one of a kind. Post here !!
Does the Swiss pink signal count??
pink signal?
B&O uses two reds with a flashing white marker light on their color position light signals to allow a head end helper to tie onto its train.
How about red over flashing red at an absolute signal at the entrance to a group of crossovers on the CTC controlled triple track BN racetrack?
The crossovers are protected both eastbound and westbound by absolute signals less than a mile apart. When set up for multiple trains, an eastbound not crossing over will trigger a red over red when it passes the entrance. Once it clears the opposite end of the crossover area, the signal changes to red over flashing red. When it clears the next block a mile or so down the line, the signal changes to yellow over red, then flashing yellow over red, and green over red as the train goes down the line. If not set up for multiple trains, it changes to red over red and stays that way until the dispatcher changes it. Since this is an absolute signal, maybe the flashing red means don’t call the dispatcher, the block is set up for multiple trains?
I would consider the gyralites that were in use at Pullman Junction in Chicago. The aspects are described in the Special Instructions in the employee timetables of the various railroads (BRC, CWI, RI, N&W).
Around where I live, the rarest aspect is GREEN![(-D]
I didn’t think of gyralights. B&O used one in Cumberland, Md. controlled by a switch tender to indicate that he had the switches lined and it was ok to cross over at Baltimore street. The P&LE had one at Mckees Rocks, Pa. that used different colors to control traffic over a diamond. Mark
flashing red means restricting. You dont have to stop you just have to go slow looking out for trains ahead.In Galesburg a flasher means you may be diverging.
Back in the day, when Bridgeport Interlocking was the junction of three railroads (ATSF, GM&O, and IC, situated at the drawbridge over “Bubbly Creek”), the signals on either side of the bridge had four heads. I’d have to dig back in my books to find out what the aspects and indications were for these.
Zardoz may remember the semaphore that used to be outside the Yard 9 Shanty at Proviso. It was the shoving signal for hump jobs to proceed out of Yard 9 (the receiving yard) toward the hump. In order to indicate that the engineer was to back up, the shove-out conductor (that was me, on more than one occasion) would manually alternate between red and yellow on the lever controlling the semaphore, causing the blade to go from horizontal to diagonal and back again repeatedly. Any other semaphore that did that would probably be regarded as malfunctioning!