Re: New Diesels for D&S?

Scott Gibbs Wrote:
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> As the D&S management team evaluates options to
> purchase diesel-electric motive power I hope they
> are getting good advice on how to de-rate the
> units for operation at 9,318 feet in Silverton.
>
> Scott

I doubt the D&S would "de-rate" any Diesel-Electric since that would be counter-productive. The load of the Train might have be reduced to compensate for the lower power output but whether this would apply to only 9,318ft I don't know. There is no requirement for full power requirements in use at Silverton anyway.

The White Pass units although operated on steep gradients weren't at much altitude, 2,885ft. The Andean experience was the HP required was 50% more than the steam equivalent. But that was at 11,000ft.

The D&RGW used their GP-9 and GP-30/40 models on Monarch and Tennessee Pass, just how less tonnage per unit vs the same gradient elsewhere at lower altitude I have never found out.

Comparable 6 motor EMD's unless turbocharged have a very low Minimum Continuous Speed and lesser top speed with full load than those with.
E.G.
90 short Tons 1650hp 4 motor 6 axle non turbo'd MCS 14MPH 31,000lb TE
95 short Tons 1650hp 6 motor 6 axle non turbo'd MCS 9MPH 45,000lb TE, turbo'd 2400hp 28MPH 45,000lb TE