Eastern Railroad Discussion > NS signal aspect question

Yesterday I was at the Hammond-Whiting (IN) Amtrak station for the station stop of No. 350. It was using track 2 and the two new mini-platforms installed in the past couple of months. What I found puzzling was the signal aspect being displayed as the train departed: red over dark over red. It apparently meant diverging clear, as would a red-green-red aspect, but I did not find this aspect described in online sources about signal aspects. 

As the train entered the block, the middle signal went to red.

Any thoughts on this? From the radio conversation it was obvious that the engineer had permission to proceed. Perhaps the signal, while brand new, was malfunctioning, and should have displayed a green aspect. 

bulb burned out ... or electrical issue ... although when a train encounters a signal aspect that has the capability of displaying a more restrictive aspect (in this case red/red/red) than the one the train crew should receive, then the crew needs to contact the disp to determine if the aspect is more favorable than the aspect the darkened aspect cod display ... if the disp states he's pulled up on the signal then the crew needs to accept the signal as it's least favorable indication other than stop if they can't determine the exact signal aspect ... unless the train is in cab signal territory at which point gbe cab signal will govern the movement ...



Edited 4 time(s). Last edit at 07/28/15 08:05 by Out_Of_Service.

Out_Of_Service Wrote:
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> bulb burned out ...

That's probably the case, although the signals are new Safetrans models, in place for only a couple of weeks, and use LEDs. Of course, even they can fail.

I have personally witnessed recently installed LED lights fail on wayside signals so it indeed can happen. 

As we were converting to LED's several years ago, we had a failures occur the same day, othere within a few days or a week. These things, like everything else being electronic have that 10% industry standard failure rate. It was the same as incandecant bulbs. We would change out perfectly good bulbs per RR maint. timelines and in the first couple of weeks afterwards, lots of B/O bulbs.

If the signal was displayed as you say,red-dark-red, and it is a home signal,it is to be considered as the most restrictive indicatiopn that signal can convey,in this case STOP! The middle aspect was in all likelyhood burned out. The dispatcher CANNOT convey any type of signal indication over the radio to a crew,and he likely has no idea what the signal would be. He can clear the signal,ie,line the route,but the interlocking logic displays the aspect of the signal based on all the criteria involved. The dispatcher CAN give the crew permission the pass a stop signal,in which case the train is to be operated at restricted speed.If the train you saw did not stop at the signal and obtain permission to pass the imperfectly displayed signal,that would be a signal violation and all hell woulkd have broken loose.

towazy Wrote:
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> If the signal was displayed as you
> say,red-dark-red, and it is a home signal,it is to
> be considered as the most restrictive indicatiopn
> that signal can convey,in this case STOP! The
> middle aspect was in all likelyhood burned out.
> The dispatcher CANNOT convey any type of signal
> indication over the radio to a crew,and he likely
> has no idea what the signal would be. He can clear
> the signal,ie,line the route,but the interlocking
> logic displays the aspect of the signal based on
> all the criteria involved. The dispatcher CAN give
> the crew permission the pass a stop signal,in
> which case the train is to be operated at
> restricted speed.If the train you saw did not stop
> at the signal and obtain permission to pass the
> imperfectly displayed signal,that would be a
> signal violation and all hell woulkd have broken
> loose.

You would be correct Tommyalphabet!
Blue24-out

That signal would be a medium clear, not a diverging clear. While they more or less mean the same thing medium clear conveys speed, diverting clear conveys route. Medium clear would be medium speed through all turn outs, cross overs and interlocking then proceed at maximum authorized speed once the entire train has cleared. And as other have said a red dark (burned out) red would be taken as a stop signal and they would have to stop at the signal even if the dispatcher talked them by, the dispatcher would include that in their orders, "upon stopping at the singal, train XXX has permission by the signal...." unless the signal had a number board which if you are talking about CD 507 shouldn't be but I haven't seen those signals since they have been upgraded. If it did have a number board it's just a restricting and they could have kept going at restricted speed without stopping not exceeding 20mph

Posted from Android

Blue 24?   HHmmmm   sounds like an old AFT codename. Since my memorey of those ID's is vague and without digging through the old artifacts,my somewhat uneducated guess would be.....DW???

Thanks for the replies. I was listening to the scanner, but only for a few minutes before the arrival of 350. I believe that the engineer and dispatcher had been communicating about the signal and route prior to the station stop. The engineer indicated that he would be crossing over to track 1 as he pulled out of the station and went at a reduced speed through the signal, that immediately changed to red-red-red. There was no mention of the dark middle signal, so presumably all were aware of whatever it was that caused the problem.