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An underrated diesel

Alco’s DL109 made a mark in southern New England
Once a proud hauler of crack passenger trains and fast freights as a DL109 diesel locomotive, New Haven test vehicle PP 716 languishes in Boston in 1968, awaiting its fate: the scrapper’s torch.
Bruce Beardsley
If Alco’s famous PA diesel is perhaps a bit overrated, as implied in the January 2004 issue of Trains magazine, then the reverse might be true of its predecessor in Schenectady’s catalog.

Industrial designer Otto Kuhler gave the early-1940s, 2,000 h.p. DL109 and predecessors a knife nose and a triple windshield. Alco gave it two 539-model switcher engines and a low-profile which seemed to leave a lot of clutter outside on the roof. While EMD E units, with their two V12 engines, somehow sounded more refined than their switcher brethren with only one prime mover, a DL109 sounded exactly like two S2’s or RS1’s running in multiple, whistling turbochargers and all. Admittedly, the DL109 never quite made it into the racehorse category epitomized by EMD’s E6. Except for the New Haven, railroads gave the DL109 and kin only cursory orders (with 60 units, NH had more DL109’s than all other roads put together).

But on New Haven’s water-level short haul, the DL109’s did well enough for more than 15 years, hauling passengers during the day, Shore Line freight at night, and, toward the end, mostly Old Colony commuters, south of Boston. Until New Haven’s 27 PA’s came along in 1948, the DL109 was the road’s signature diesel. The 539 inline engine was heavy, so two in a single unit meant good weight on drivers, yielding a creditable tractive effort. Plus, NH’s relatively short haul meant frequent turnarounds where Alco-savvy shop forces could keep close track of the units, a benefit which also enabled New Haven’s PA’s to be better performers than they were for some other roads.

And there was this: Reportedly, on that occasional winter day when all of southern New England was at 20 below zero, the only thing on the New York, New Haven  & Hartford Railroad guaranteed not to be frozen up was any diesel with a 539 prime mover.

Although New Haven’s DL109’s served well, by the late 1950s new FL9’s and freight hood units spelled the end for the knife-nosed Alcos. One, however, lasted almost as long as the New Haven itself did. In this 1968 photo, NH PP716, formerly 0716, languishes at Dover Street Yard in Boston, a year away from the property cleanup of successor Penn Central that will clear the yard of junkers and consign the DL109’s to memory. Literally derated, she long ago gave up one of her engines to accommodate third-rail testing equipment, the assignment that allowed her to outlive all her sisters. At Dover Street, her orange paint has turned pink, and she and her scrap line companions have lost all window glass to vandalism. In less than a year she will be hauled off to be cut up, leaving the DL109—except in southern New England—a more or less footnote in diesel history. And underrated, for sure.

First published in Winter 2006 Classic Trains magazine.

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Three stories written and photographed by Jim Shaughnessy.


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