>>> Unlike car traffic signals, which have limited nationwide meanings, "there are
>>> dozens and dozens of signal combinations," which can hold different meanings
>>> under tracks owned by different railroads, Sumwalt said.

>>> If this is indeed true, it seems like it's a massive accident waiting to happen!
>>> Has no effort ever been launched to address this nightmare? The NTSB seems to
>>> be the most logical agency to do so.

It most emphatically is NOT TRUE! At least only very rarely. Not only that, but GCOR vs NORAC signal rule differences are superficial and minor. The average railfan couldn't even tell which is being used at any given site unless one of the non-shared aspects be presented or he had inside information.

As usual, the media left out a whole major set of facts. And Mr. Sumwalt, NTSB's loose cannon, needs to have his credentials re-verified. And fast! The FRA for at least 60 years that I know of, has taken high exception to oddball signal meanings everywhere they have been found - with fines and shutdown orders to follow if compliance was not prompt.

It is true that some of the more esoteric and unusual signal aspects can confuse some railfans and the public at large - but so what. Locomotive engineers are thoroughly professional and technologically qualified to do what they do. Moreover, they are specifially tested and qualified on every inch of track thay operate on - thoroughly familiar with the location and capability of every appliance, constraint and circumstance on the line. This is not to say that ordinary and expectable human error is not an every day concern, as it is with all human activities; nor that training and qualification standards might not fall short somewhere.

What was left out by the media? Only that another signal was between the "Red Over Yellow" at the crossover, and the crash site, which signal was just plain "Red", because of a train ahead - as should be expected after a red over yellow.

But that's not even the whole story. After the train had flagged past the red signal, a regular station stop ensued, followed by an approach to a slow ordered (and flagged) work-area.

Not only was the train under the restriction of "flagging" a red signal, it was also under the restriction of the slow order. In addition, the train was governed at the time by the universal (federally imposed) "Delayed in block Rule", which requires that if a train stops for any reason (such as a station stop), it must then proceed to the next signal at slow speed (40mph or less). Of course, all railroad rulebooks require that when multiple governing conditions apply at the same time, the most restrictive condtion must apply.

The inexplicable event followed, wherein the engineer carried out the least restrictive condition, instead of the most restrictive one. He must have realized his error when he applied the emergency brakes at the work area red flag - at which point he still couldn't see the fouled track up ahead. But alas, the 40mph allowed by the delayed in block rule was too fast to then allow a safe stop before the train ahead was hit.

I would suppose that he got all distracted by the station stop and forgot about the other more restrictive conditions.

Ironically, the "Delayed in Block Rule" itself, was imposed after an accident was supposedly caused by an engineer passing a yellow (approach) signal followed by a station stop - After which the engineer apparently forgot his last signal aspect and proceeded off at full speed into the next signal which was red.

I wonder now how many more layers of rules to prevent this "partial forgeting" will be imposed, each in turn causing another govening condition to be forgotten. Instead, some form of ATS (Automatic Train Stop) along with cab signalling, should be set up - to more effectively prevent understandable human error from causing accidents.

The current fancy buzz-word is PTS (Positive Train separation), which generally refers to newer technologies (satelite and radio ranging) being overlayed over existing signal systems. Of course the FRA and the railroads are very reluctant to impose it because of the billions it would cost to cover all mainline trackage and because it is still experimental, unproven, and generally still unreliable where it has been tried.

However, anymore, virtually every existing mainline track circuit in America is already an electronic coded track circuit, or soon will be under normal re-capitalization programs. Even those not yet electronic are still coded. The main difference between lines with operating cab signal/ATS systems and those without, is how the coding is arranged. It is therefore possible using existing off the shelf components, most of which are already installed, to cost effectively re-arrange the coding. This could extend current cab signal territory almost universally - and without undue financial burdens.

Of course, that would keep me and those I work with employed - as that is the centerpoint of our profession.

OPB