"Gas Turbine Electric" locomotives for the Union Pacific: specifically the 8500 hp "Big Blow" turbines, road numbers 1-30, built in the late 1950s. Each of these was a pair (one cab, one "booster," but the two were dissimilar mechanically and had to operate together, unlike cab and booster diesels) of CC units. Their trucks were recycled on the U50C 5000 hp twin-engine diesels GE built for U.P. around 1970.
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Phil Hom:
Yes, I thought of those after posting before. Comparing pictures, however, they aren't quite the same.
(i) The trucks on the GTE/U50C have even spacing of axles, whereas those on the E40 don't seem to be quite even. (Even axle-spacing was unusual for C trucks on U.S. locomotives, though the EMD truck used on pre-Dash-2 SD units had it. British CC diesels, however, typically did have even spacing, despite the fact that there would be two traction motors between one pair of axles and only one between the other pair.)
(ii) The two drop equalizers on a side of the GTE/U50C truck seem to have the same springing arrangement, whereas on the E40 they were different: two pairs of coil springs to one, one pair of coil and one set of semi-elliptical on the other if I remember the picture right.
(((Of course, that's just the visual difference: given that one was for a lightweight passenger locomotive and the other for heavy freight power, there may well have been quite fundamental design differences. The U.P., which still ran some big steam when they ordered the GTE, probably was willing to live with heavier dynamic forces from its locomotives than the New Haven, which operated its passenger electrics over the elderly Park Avenue viaduct into Grand Central!)))
