How much did ditch lights improve night visibility from the cab? Under what conditions do they help the most? Are there conditions where ditch lights reduce visability?
dd
I believe ditch lights were first introduced by CN in the 80s…correct me if I’m wrong.
Ditch lights add a lot of visibility to the area around the front of the locomotives.
All the old BC Rail loco’s now owned by CN actually had 2 sets of ditch lights on each locomotive. They were all off-set so when the locomotive was going around turns more area would be lit up on either side of the right-of-way.
These locomotives are now making their way around the CN network, I see them all the time in the Fraser Canyon here in British Columbia, not sure how much farther they have wandered in recent times.
Only time it seems that it isn’t much better is in heavy fog, it seems that you just reflect most of the fog back and you just get a big white haze in front of you, I figure it’s best to keep them on, though, as you will be seen sooner by those in front of you.
Wow!
I never knew that, thanks
Ok it’s a good thing that this topic came up because I need to ask this Question.
When you look at an everyday Locomotive the first thing I see is that on a lot RR power is that the Ditch lights are on the Locomotives in different areas of the units.
Why are the Ditch lights on some Locomotives on the upper part of the walk way and on others they are on the lower part of the of the walk way,on the FRONT of the Locomotives? If you know what I mean?
Are you noticing that same locomotive model on same railroad has lights mounted in different locations? Or lights are mounted differently on different models? Dave Williams
Yes! Both.
I knew that ditch lights significantly improve visibility of the train. It certainly makes railfanning easier. But I was wondering if there was more too them than just external visability. You all have confirmed that there is.
I also have noticed different practices in mounting the ditch lights. And it seems to me that the way the “ditch lights” are mounted on Amtrak’s locomotives are much too high to give the fog/blowing snow benefit that AJT so benefited from.
Thanks for the contributions.
dd
An interesting discussion, but the posted comments leave me wondering about who had ditch lights first. Alaska in 1983 is mentioned, and BC Rail before that, then they were supposed to be widespread on CN by 1987, and mandated in Canada by 1989. But another poster says that CP started them. Can we assemble a reasonable timeline out of this?
Certainly it makes sense that they started in areas where rocks on the side of the tracks would be a problem, and I can see Alaska and BC being ‘leaders’ in that sense.
Jim
Interesting thread. So, if you do see a large rock(s) or tree(s) fouling the tracks, is there enough time to go into emergency and avoid damage to the locomotives? And, how often does this happen? Certain tree species are more likely than others to topple over in high winds or when the soil is saturated, so I’m wondering if this happens more in some geographic regions than in others.
Yes, I do know what you mean. The difference is maintenance access and ease of dealing with MU jumpers. It is easier to deal with them if the ditch lights are mounted on top of the walkway, but if the goal is to get them closer to motorist’s eye level, then lower is better. Conrail opted for the latter, feeling visibility trumped maintenance. Other roads felt the difference in height was too small to make a real difference, so they went with the walkway mount.
I would say it depends what kind of climate, terrain, and grade a train under these conditions is running on. FOR EXAMPLE: (An engineer has a 22,000 ton coal drag w/ two SD70MACs and one SD40-2, on a 2.8% grade downhill, adverage speed 20mph) If this engineer saw a tree on the tracks w/ the ditch lights (in the dark of night w/ heavy rain) his range vision might be 500ft or so. He then applys the brakes in emergancy, at this time given the situation he might hit that tree on the tracks.
Rock tumbling, and tree toppeling happens more in areas in which tracks run through decidious forests, and mountainous areas. This could also happen in valley areas w/ poor runoff. Area’s with what I like to call “lose soil” might also cause rock, and tree problems.
I know on UP’s Yellowstone Branch they kept the trees cut back about 50 feet on either side of the track to keep the trees from falling on the tracks in snow storms. Of course that route is now a snowmobile trail.
dd
[quote]
QUOTE: Originally posted by M.W. Hemphill
Mac: The very first ditch lights I saw were in Alaska, in 1983. Some of their units had them applied by the shops. I think BC Rail had them before that, however.
CN was the first Class I that I am aware of to make a general practice of ditch lights, and by 1987 they were widespread. Union Pacific’s Steve Lee saw a night shot I took at Boston Bar in February 1987 that was published in a magazine, and called me to get a copy so he could make 8x10 prints to pass around to UP mechanical and operating department officials to help make the case for ditch lights at UP.
dd: You’ll note that the first roads to go for ditch lights were all in northern latitudes with short days six months of the year, heavy curvature, and remote routes in rough country. As far as I know the original intent of ditch lights on all of these northern roads was to give the engine crew better visibility to the side of the track, and especially in curves, as the ditch lights were aimed outward, not straight down the track. That enabled a train crew too see rocks, trees, and large animals sooner than otherwise. The low mounting reduces glare that reflects back at the engine crew in fog or precipitation (which is why many railroads have deleted above-cab headlights). Low mounting also casts shadows to improve the contrast of an object that’s fallen close enough to the gauge to be struck by the locomotive pilot, but not necessarily on the track. Often that’s where rocks land – just outside the rail, and a center-mounted, high headlight isn’t very good at picking them out against the background until the last second. Thus, on these roads, the original intent of the ditch light was for the benefit of the engine crew.
It was later realized that ditch lights gave greater visibility of the train to motorists, too. Their adoption in the U.S., which became an FRA mandate, is for that purpose, rather than the previous purpose, which is why
I recall from an earlier discussion that part of the rationale behind the ditchlights is an easily recognizable triangle of lights, which becomes a symbol of a RR, if you will. If you think about it, it would be easy to just skip the center headlight, leaving you with two lights, just like a road vehicle, and not sacrifice anything. The third light makes it distictive.
I think the ability by others to see the train is greatly helped by the ditch lights. The triangulation of the three lights help you determine the speed of an approaching train. It also helps if train drivers dip the headlights.
I don’t think train drivers can ‘dip’ a locomotive’s headlights and ditchlights - short of turning them off. ‘Dipping’ or going to low beam requires a second bulb or bulb filament and (usually) some fancy lens or reflector work and and I haven’t seen any locomotive headlights with that arrangement.
I also don’t think it would be desireable, if maximum visibility to motorists and others crossing the tracks is the aim.
Jim
I noticed yesterday, while passing the CSX yard, several locomotives had a very small light, centered between the ditch lights. Ditch lights were (I think) not on at the time. I think the small light has probably been there all the time; it was overcast yesterday & I probably wouldn’t have seen it if the sun had been out. It looked to be maybe 1" or less diameter. Looked more like an indicator light on a control panel.
I have seen the lights dimmed, though - most likely by reducing the voltage to the bulb(s).
Sounds like the front walkway light.