Steam & Excursion > Diesel locomotives in consist with steam locomotives

I have been watching some of the video clips on trainorders of 844 and 3985 and I noticed that sometimes they run with diesel locomotives in the consist. Do the steam locomotives need help pulling or is it more for the diesels braking (dynamic) abilities? Also, when the diesels are in the consist, are they MUed to the steam locomotive or is there a separate crew in the diesels?

Cheers
billnict

billnict Wrote:
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> I have been watching some of the video clips on
> trainorders of 844 and 3985 and I noticed that
> sometimes they run with diesel locomotives in the
> consist. Do the steam locomotives need help
> pulling or is it more for the diesels braking
> (dynamic) abilities? Also, when the diesels are
> in the consist, are they MUed to the steam
> locomotive or is there a separate crew in the
> diesels?
>
> Cheers
> billnict

Nowadays, most rairoads want a diesel in the consist in case something breaks on the steam power (U.P. is often an exception to this). That way they can at least drag the train into a siding and get it out of the way of their coal trains and doublestacks. Also, yes the dynamic braking is a valuable asset
when decending any grade. Saves a lot on brake shoes and is a lot safer. Some steam locomotive are now equipped with an MU device where the steam crew can control a trailing diesel unit. I know that the S.P. 4449 and S.P.& S. 700 have this feature as well as several others. I'm not sure if 844 and 3985 are so equipped. Another reason (especially on Amtrak sponsored trips) is to supply head end power to the train for lighting, AC, and etc.

esinclair Wrote:
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I know
> that the S.P. 4449 and S.P.& S. 700 have this
> feature as well as several others. I'm not sure if
> 844 and 3985 are so equipped. Another reason
> (especially on Amtrak sponsored trips) is to
> supply head end power to the train for lighting,
> AC, and etc.

Here's the MU control on the SP&S 700. You probably won't find any MU controls that look alike on any two steam locomotives as all are built as individual projects. I built this one from parts obtained from several different locomotives (GE and EMD) that were being scrapped.

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billnict Wrote:
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> > sometimes they run with diesel locomotives in the
> consist.

In general, does "consist" refer to just the power, or the entire train?

Doug Wrote:
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> In general, does "consist" refer to just the
> power, or the entire train?

When I think of consist I think it refers to just the power I may be wrong though.

Cheers!
billnict

Clinchfield 4-6-0 was the first with such a "black Box" I think, in the early 1970's - to control its two blind F-units. NKP 765 has had its own black box since it came out for its Second Career in 1979 (or 2.0 in modern computer parlance). I expect you will find that many mainline "excursion" steamers are so equipped in recent years. Even though the 765 seldom needed to MU with a diesel, it was a feature that seemed to make the Class One carriers a bit more comfortable, just like the modern 26L brake system did. It is always a "hoot" to look at the back of the 765's tender and see an "EMD" marked MU jumper receptacle!

NKP779 Wrote:
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> It is always a "hoot" to look at the back of
> the 765's tender and see an "EMD" marked MU jumper
> receptacle!

Here's the EMD marking visible on the MU receptacle which is mounted just inboard of the left rear tender step on the SP&S 700.

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