Milwaukee Road class A

Specifications
Specifications
Configuration:;
• Whyte	4-4-2
• UIC	2′B1′ h2
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Driver dia.	84 in (2,134 mm)
Length	88 ft 8 in (27.03 m)
Height	14 ft 4 in (4.37 m)
Adhesive weight	144,500 lb (65,500 kilograms; 65.5 metric tons)
Total weight	537,000 lb (244,000 kilograms; 244 metric tons)
Fuel type	Oil
Fuel capacity	4,000 US gal (15,000 L; 3,300 imp gal)
Water cap.	13,000 US gal (49,000 L; 11,000 imp gal)
Boiler pressure	300 psi (2.07 MPa)
Heating surface:
• Firebox	69 sq ft (6.4 m2)
• Total surface	3,245 sq ft (301.5 m2)
Superheater:;
• Heating area	1,029 sq ft (95.6 m2)
Cylinders	Two
Cylinder size	19 in × 28 in (483 mm × 711 mm)

Type and origin
Type and origin
Builder	American Locomotive Company
Serial number	68684 (1), 68685 (2), 68729 (3), 68828 (4)
Build date	May 1935 (2), May 1936, April 1937
Total produced	4

Milwaukee Road Class A
Milwaukee Road Class A
	A postcard depicts the Milwaukee Road class A #2 in 1935.
Builder
Type and origin
Builder	American Locomotive Company
Serial number	68684 (1), 68685 (2), 68729 (3), 68828 (4)
Build date	May 1935 (2), May 1936, April 1937
Total produced	4
Configuration:;
Specifications
Configuration:;
• Whyte	4-4-2
• UIC	2′B1′ h2
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Driver dia.	84 in (2,134 mm)
Length	88 ft 8 in (27.03 m)
Height	14 ft 4 in (4.37 m)
Adhesive weight	144,500 lb (65,500 kilograms; 65.5 metric tons)
Total weight	537,000 lb (244,000 kilograms; 244 metric tons)
Fuel type	Oil
Fuel capacity	4,000 US gal (15,000 L; 3,300 imp gal)
Water cap.	13,000 US gal (49,000 L; 11,000 imp gal)
Boiler pressure	300 psi (2.07 MPa)
Heating surface:
• Firebox	69 sq ft (6.4 m2)
• Total surface	3,245 sq ft (301.5 m2)
Superheater:;
• Heating area	1,029 sq ft (95.6 m2)
Cylinders	Two
Cylinder size	19 in × 28 in (483 mm × 711 mm)
Maximum speed
Performance figures
Maximum speed	112.5 mph (181 km/h)
Tractive effort	30,685 lbf (136.49 kN)
Factor of adh.	4.71
Operators
Career
Operators	Milwaukee Road
Class	A
Numbers	1 – 4
Retired	1949–1951
Disposition	All scrapped.

The Milwaukee Road Class "A" was a class of high-speed, streamlined 4-4-2 "Atlantic" type steam locomotives built by the American Locomotive Company (ALCO) from 1935 to 1937 to haul the Milwaukee Road's Hiawatha express passenger trains. Numbered from No. 1 to No. 4, they were among the last Atlantic type locomotives built in the United States, and certainly the largest and most powerful. The class were the first locomotives in the world built for daily operation at over 100 mph (160 km/h), and the first class built completely streamlined, bearing their casings their entire lives. Although partially supplanted by the larger class "F7" Hudsons from 1937, they remained in top-flight service until the end. Locomotive No. 3 was taken out of service in 1949 and cannibalized for spare parts to keep the other three running until 1951.