Drawings of the never-built EMD GP50T?


"Feeling the slack run out on the power...". Just one of my many queries, (most of which I will forget--keep the coffee coming Flo!).

When you go to Dyn 8 the head end slack runs IN, correct? But the trailing end slack runs out at the same time...which must end with a big bang when all the trailing end slack runs back in (heading downhill). Unless I'm not understanding something...which is quite possible....

Aside: I have to thank you for all your input. REALLY helpful to my understanding of it alone to speak with someone who actually ran a real train up the grade....
 
No sir I mean there were little to no dynamic brakes at 20 mph or thereabouts or less. So the slack ran out. The flat range dynamic brakes don't work very well at slower speeds. The DRGW SP had extended range dyn brakes that worked down to a crawl. I was referring to the old green BN units we had on trackage rights trains.
 
Doh! You did say it. I just swung...and missed.

I can easily see how NON-extended range dynamic brakes could have wormed their way onto Rio Grande rails. Heck, there is at least one photo of red and gray CB&Q units in one of the Colorado canyons, and that was a LONG time before the idea of run-through units/power swapping came into vogue. IIRC that photo dates back to the early sixties (it's in one of the Rio Grande photo books I'm currently collecting. Buying up, as it were). The extended range DB might not have been available then, of course.

I have the idea the arrival of the GP30 changed a lot of things for Rio Grande thinking, and even if the GP35s were something of a disappointment.

I do know the GP35s were de-rated in such a way as to remove their cab-controllable status. Plywood covering over the windows, I think, which made them "B-units"

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So...RG operating rules (AFAIK) specify only the front twenty four axles were allowed to go into dynamic braking. Any others which might be trailing--mid-train helpers were not allowed to go into dynamic mode at all, even if it might have worked out.

This would be around the '80s though. Today there is distributed power, so I'm sure all those old rules have long-since been thrown into the dustbin of history.

But "back in the day..."....
 
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"back in the day", now that brings back memories. I miss back in the day for sure. RRing was way more heart and soul than cold bottom line. It was a better time, for me anyway. Not that I am all that old school. It was just such a much, better time for us all in RR terms. I miss it, would prolly still be there, but, not in today's atmosphere.

BTW those SD40T-2's, well the DRGW ones were great locomotives. They were certainly my most favorable units. Man how they would pull, they had no give up in them, would give you all they had, all day, every day, and all day long. Just pure pulling power, what heart they had.
 
gjslsffan said:
No sir I mean there were little to no dynamic brakes at 20 mph or thereabouts or less. So the slack ran out. The flat range dynamic brakes don't work very well at slower speeds. The DRGW SP had extended range dyn brakes that worked down to a crawl. I was referring to the old green BN units we had on trackage rights trains.
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That's not a fun feeling! I knew the difference between standard and extended range "on paper" but until you experience it the difference is just academic. Those taper dynamics on the geeps were interesting to get a feel for as well.

We've had a few engineer classes lately so relating the difference between standard and extended range dynamics has turned me into a bit of a broken record. And pointing out the places you don't want to come out of dynamics before the students find out the hard way has kept me alert (we've got several of those places on our little undulating territory).
 
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