Flashing signal lights

On the AT&SF a flashing yellow supposedly signalled approach medium. I have also read about flashing red and green signals on this forum.
Can anyone tell me the flash rate and if it was different depending on the signal color?

Thanks
Al

 

Flashing yellows are common, well moreso than flashing greens and particularly reds. Flashing greens were trialled some years back on the East Coast Main Line north of Peterborough in the UK.

A quick look around suggests something in the region of 25-27 flashes a minute but that would be dependant on the requirements and the flasher used. The Westinghouse SafeFlash unit used on level crossings is rated for 40-50/minute though I do recall 43/minute being preferred for LX installations.

 

NORAC Signal Chart

Al, hello ! Have this chart, hope it'll fit the window - shows (flashing) aspects we used on Conrail ! (Hope it's not too much info !!!) Bob C.

 

being a long time ATSF fan and having driven crews for them for a few months I was able to see any new changes that effected the train crews. The newest was the flashing red. It means start and proceed at restricted speed if you are stopped and read it like a flashing yellow if you are moving.

Shannon

 

Thanks Bob - I'm overwhelmed!! Guess Conrail kept the signals from each railroad that made up Conrail and before that PC and others. Did they ever standardize on any lines and has or will NC/CSX ever do that?
Al

 

Hi,again, Al. Conrail did inherit several different signal formats from it's constituent roads. My territory was mostly ex-PRR, so Position Light signals. Conrail began "improvements" as tracks were moved/upgraded and old equipment was replaced with color light signals - sometimes as one location on a track segment, or an interlocking/CP point might get some/all signal heads replaced. Signal rules were also changed from Rule 251 /261 to TCS, requiring addition of bi-directional automatic signals and replacement of "Low Home"(dwarf) signals with full height mast and bridge mounted heads - usually color light type. A lot of us old guys had an awful time re-learning aspects/indications. NS has been upgrading to color lights as they can, and the old PRRs are getting more scarce. Guess modern modelers can use either - or BOTH !!!! Bob C.

 

Take a look at this video I took at Emory near Atlanta. At the 0:12 mark you can see a closeup of an "Approach Limited" signal, which is Yellow over Flashing Green. You should be able to get the flash rate from that. All flashing signals I have seen seem to be about the same rate. Jamie

[ame="http://www.youtube.com/watch?v=ueNmRSuh1VQ&feature=related"]YouTube - CSX Q618 Mixed Freight at Emory, GA[/ame]

 

Having seen these charts a few times, I've always wondered; is there some rule(s) that make them easier to understand?

Several of these have like 15 different aspects that mean the same thing. It seems strange that it would be straight memorization to remember them all, but maybe it is. How do they teach these to new engineers?

 

There must be even more--I don't see many of the CSX aspects used on former Seaboard territories down here in the south listed in this chart. Jamie

EDIT: I see this is the NORAC chart, which I believe on CSX only applies to former Conrail (historically PRR/NYC) territories.

 

Thanks Jamie. I got 45 flashes/minute which agrees with what others have said.
This is getting too complicated. I think I will go with one light/signal like this:

http://broadway.pennsyrr.com/Rail/Signal/abs_atsf/dt_abs_2.gif

Thanks all for the info.

Al

 

You could use a signalling system, e.g. from Digitrax. They support flashing yellow, and you don't need DCC to implement it.

Just a thought.

hth
Michael

 

Leo, yes, the "Rule XXXx" indicates the Employee Timetable rule the signal refers to for required response/action. There are really only 3 signal formats on the card - PRR Position light, NORAC Color light, and a color/position light whose origin I can't claim to know.Was trying to get the reverse of the card up (the "Rules" are digested there) but the scanner isn't cooperating right now. Many companies had their own signal display systems, so you may see more, or may learn of conflicting "rules" for a similar display, or additional aspects (what it looks like) and indications (what to do when you see it) not shown here. Lots of CR guys saw nothing but PRR signals until the CR upgrades began. I ran from Pittsburgh to Harrisburg - ALL Position light until the '90s and then changed piecemeal, so we had to know BOTH displays, and WHERE to expect which type, (could be REAL FUN in frequent HEAVY FOG !). I'll shut up now, and listen for a bit. Bob C.

 

What bright spark dreamt up that scenario? A flashing red that means the same as a flashing yellow?
In my world red = danger/stop.

 

Shannon, What's the "Rule" on that flashing red? -any other lights displayed/visible on the signal/head ?- dwarf or high signal ?- automatic or "Home" signal ? - location and control method makes a difference in what a signal indicates (MORE Qualification info for the crew. Usually (until the last of CR) our flashing signals indicated a speed upgrade of the indication. Rule 282a (Advance Approach - see the card) wasn't added to our books 'til about '95 or '96 (Proceed prepared to STOP at second signal - reduce to LIMITED speed on passing signal). Just saying I haven't heard of such an equivalent pair of indications. Bob C.

 

You guys should all check out this webpage...

Railroad Signalling: North American Signaling and Safety

Al, I don't think the flash rate ever depends on the color of the signal. It probably only varies with certain makes of signal. And the speed of the flash is never part of the signal aspect.

I don't think that what was said about flashing red = flashing yellow is correct. See the ATSF chart at the link above. Flashing red was restricted speed; unlike solid red it didn't require the train to stop at the signal.

 

Al, Found what I think you require in explaination of all those pretty colored lights (at least on NORAC)... will give you the basics of what must be done in response to a signal display. You must learn this stuff - you won't have time to look it up out on the tracks.
http://modernrailroading.com/DigitalLibrary/Norac/signalaspectsandindications.htm

Some additional signals are used on other roads, but mostly, these will carry over, probably by Rule #, to most companies, with some variations. Hope this helps.
Bob C. :tb-nerd:

 

Good grief. I knew US signal aspects were a bit, er, odd, but I'm guessing now that back in the day the signal engineers' convention gave an annual prize for the most bizarre new way to convey information.

Thankfully it seems the highway engineers didn't go to the same convention

 

It is scary Mike. I wonder if the first prize was paid in C$1 coins?...