ALCO DL-109

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ALCO DL-109
An ALCO DL-107 pictured in a publicity postcard for the NYC-SOU-SAL Florida Sunbeam
Type and origin Power type Diesel-electric Builder American Locomotive Company (ALCO) Model DL-109 Build date December 1939–April 1945 Total produced 74 Cab units + 4 Booster units
Specifications Configuration: ​  • AAR A1A-A1A Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Trucks ALCO Trimount Wheel diameter 40 in (1,016 mm) Minimum curve 21° (274.37 ft or 83.63 m) Wheelbase 58 ft 4 in (17.78 m) Length DL-103b: 78 ft 11 in (24.05 m) DL-105, DL-107, DL-109: 74 ft 6+1⁄2 in (22.72 m) DL-108, DL-110: 72 ft 4 in (22.05 m) Width 10 ft (3.05 m) Height 14 ft 6 in (4.42 m) Loco weight DL-103b: 339,000 lb (154,000 kg) DL-105, DL-107, DL-109: 331,000–357,500 lb (150,139.1–162,159.3 kilograms) DL-108, DL-110: 300,700 lb (136,395.2 kilograms) Fuel capacity 1,200 US gal (4,500 L; 1,000 imp gal) Prime mover DL-103b: (2) Alco 538T DL-105, DL-107/DL-108, DL-109/DL-110: (2) Alco 539T RPM range 315–740 Engine type (2) Straight-6 Four-stroke diesel Aspiration Turbocharger Generator (2) GE GT-557 Traction motors Passenger: (4) GE 730 Freight: (4) GE 726 Cylinders 6 Cylinder size 12 in × 13 in (305 mm × 330 mm) Gear ratio DL-103b: 58:25 DL-105: 71:21 DL-107/DL-108: 64:19 DL-109/DL-110: 58:25 (NH units 64:19) Loco brake Straight air Train brakes Air
Performance figures Maximum speed 80–120 mph (129–193 km/h) Power output 2,000 hp (1,490 kW) Tractive effort 56,250 lb (25,510 kg)
Career Class MILW: 20-AP-6, NH: DER-1/b/c Locale U.S.A. Disposition All scrapped

The ALCO DL-109 was one of six models of A1A-A1A diesel locomotives built to haul passenger trains by the American Locomotive Company (ALCO) between December, 1939 and April, 1945 ("DL" stands for Diesel Locomotive). They were of a cab unit design, and both cab-equipped lead A units DL-103b, DL-105, DL-107, DL-109 and cabless booster B units DL-108, DL-110 models were built. The units were styled by noted industrial designer Otto Kuhler, who incorporated into his characteristic cab (US Patent D121,219) the trademark three-piece windshield design. A total of 74 cab units and four cabless booster units were built.