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Re: why no Dynamic Brakes? -lights
Author: Dr Zarkoff
Date: 07-02-2019 - 11:41
> Thinking back on it again, Hutch might have said "full light package" referring to the extra lights for push-pull operation,
For push pull operation, that would be only red markers, on the other hand I suspect he was referring to the SP's standard "light package", which included, in addition to the CFR mandated headlight, white and red mars lights. At the time, the green/white class lights could be used as "red markers" (the SP discontinued this practice in the 1980s, if not earlier).
> mainly a taillight for use when pushing (when did the modern practice of just a dim headlight on the trailing unit become standard?).
The headlights on trailing units are supposed to be extinguished. The "headlight" on a passenger locomotive being used in push mode on the rear of a push-pull passenger train is turned off, with the red markers used instead. Since a train is identified by the "leading locomotive", the pushing locomotive's number lights are turned off and the cab car's are turned on.
Headlight non-use with locomotives in push mode is easily confused with DT power on the rear of a freight train, which is a completely different type of service covered by its own particular set of rules and regulations, and these require the rear headlight be on dim and the red markers NOT be used. I didn't pay all that much attention to freight engines after about 1995, and ISTR that beginning about then, they were being built sans white/green/red class-marker lights. Passenger locomotives are still built with red markers.
> I'm not remembering a lot more lights than that, or really any more lights than Caltrain uses now (no ditch lights either - those were added later). Don't remember whether they had a Mars light, or the flashing-headlight version - but they probably did, with all the grade crossings. I was working (not for the railroad) in SF when the Caltrans trains were bought, and got a tour on a test train.
The white mars lights went away during the late 1980s/early to mid 1990s from both locomotives and cab cars with the establishment of ditch lights as suitable visual warning devices. BTW ditch lights aren't required to flash, but if they are set up to do so, there are a prescribed limits on the flash rate. About the same time the red mars light, which had devolved into a red strobe in many cases, went away in favor of radio communication. The disappearance of both was a maintenance cost thing.
For push pull operation, that would be only red markers, on the other hand I suspect he was referring to the SP's standard "light package", which included, in addition to the CFR mandated headlight, white and red mars lights. At the time, the green/white class lights could be used as "red markers" (the SP discontinued this practice in the 1980s, if not earlier).
> mainly a taillight for use when pushing (when did the modern practice of just a dim headlight on the trailing unit become standard?).
The headlights on trailing units are supposed to be extinguished. The "headlight" on a passenger locomotive being used in push mode on the rear of a push-pull passenger train is turned off, with the red markers used instead. Since a train is identified by the "leading locomotive", the pushing locomotive's number lights are turned off and the cab car's are turned on.
Headlight non-use with locomotives in push mode is easily confused with DT power on the rear of a freight train, which is a completely different type of service covered by its own particular set of rules and regulations, and these require the rear headlight be on dim and the red markers NOT be used. I didn't pay all that much attention to freight engines after about 1995, and ISTR that beginning about then, they were being built sans white/green/red class-marker lights. Passenger locomotives are still built with red markers.
> I'm not remembering a lot more lights than that, or really any more lights than Caltrain uses now (no ditch lights either - those were added later). Don't remember whether they had a Mars light, or the flashing-headlight version - but they probably did, with all the grade crossings. I was working (not for the railroad) in SF when the Caltrans trains were bought, and got a tour on a test train.
The white mars lights went away during the late 1980s/early to mid 1990s from both locomotives and cab cars with the establishment of ditch lights as suitable visual warning devices. BTW ditch lights aren't required to flash, but if they are set up to do so, there are a prescribed limits on the flash rate. About the same time the red mars light, which had devolved into a red strobe in many cases, went away in favor of radio communication. The disappearance of both was a maintenance cost thing.
