Western Railroad Discussion > DPU train handling question

Occasionally I see stack trains running outside my window on UP's Baird Sub with a 1x1 power configuration. My question is: If the lead unit craps out, does the rulebook allow for any forward movement of the train to the next siding with the rear unit pushing? Does it allow for any forward movement at all, or does the crew have to hike back to the DPU and get permission to pull back to the last siding to wait for help? Can't imagine they would let you go too far or too fast with a motor pushing the whole train. Perhaps it depends on the situation? If you have to always go back, it leads me to wonder about the wisdom of running DPU power in this configuration.

TIA for any replies,
Joel Gilmore
Fort Worth

If the lead unit "craps out" then you have no control over the DP unit. You have to have both radio and air signals to make the DPU work. As for pulling the train back into a side or to clear the main you should be able to do that from the DP unit by setting it up for conventional running.-BMT

You can run the DPU independent of the lead. As long as there isn't an airbrake or computer problem on the lead loco then you can run the train using only the DP.

>UPMW2-1083 Wrote:
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If the lead unit "craps out" then you have no control over the DP unit. You have to have both radio and air signals to make the DPU work. As for pulling the train back into a side or to clear the main you should be able to do that from the DP unit by setting it up for conventional running.-BMT





BN4364 Wrote:
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> You can run the DPU independent of the lead. As
> long as there isn't an airbrake or computer
> problem on the lead loco then you can run the
> train using only the DP.



Okay, who's right here?


V

SLOCONDR

SLOCONDR Wrote:
-------------------------------------------------------
> Okay, who's right here?
>
>
> V
>
> SLOCONDR


If the lead (controlling) unit on a DP train "craps out", as in simply dies and can't be restarted, it can still be used to control the remaining units (both on the head-end and DP units) normally; it's just the lead unit won't be loading. If the lead unit "craps out" with a computer failure or air brake failure then you're dead. I have also seen the unit work just fine but have had the DP radios (there are 2) fail and then the train is dead as a DP train until it can be re-linked with a different lead unit.

BN4363 had it right. If there is another train around, they would take one off of that train. The only way that they would use the dpu, is if there no train within 10 miles of that train.

Railbaron Wrote:
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> SLOCONDR Wrote:
> --------------------------------------------------
> -----
> > Okay, who's right here?
> >
> >
> > V
> >
> > SLOCONDR
>
>
> If the lead (controlling) unit on a DP train
> "craps out", as in simply dies and can't be
> restarted, it can still be used to control the
> remaining units (both on the head-end and DP
> units) normally; it's just the lead unit won't be
> loading. If the lead unit "craps out" with a
> computer failure or air brake failure then you're
> dead. I have also seen the unit work just fine but
> have had the DP radios (there are 2) fail and then
> the train is dead as a DP train until it can be
> re-linked with a different lead unit.



Thanks RB. Then technically both are correct. DPU's were fairly new, and not used here on the coast, when I retired, so this DPU stuff is all foreign as to how it works to me.


V

SLOCONDR

If running 1X1 and the leader shuts down, you'll be dead in the water as soon as the main reservoir drops. Doug

hoggerdoug Wrote:
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> If running 1X1 and the leader shuts down, you'll
> be dead in the water as soon as the main reservoir
> drops. Doug


that is right