CN U-1-a and U-1-b

Specifications
Specifications
Configuration:;
• Whyte	4-8-2
• UIC	2′D1′ h2
Gauge	4 ft 8+1⁄2 in (1,435 mm)
Leading dia.	34+1⁄4 in (0.870 m)
Driver dia.	73 in (1.854 m)
Trailing dia.	43 in (1.092 m)
Minimum curve	16°
Wheelbase	Loco: 41 ft 9 in (12.73 m)
Length	90 ft 4+1⁄4 in (27.540 m)
Width	10 ft 9+5⁄8 in (3.292 m)
Adhesive weight	233,790–235,390 lb (106.05–106.77 tonnes)
Loco weight	355,570–355,570 lb (161.28–161.28 tonnes)
Total weight	602,600–603,870 lb (273.33–273.91 tonnes)
Fuel type	Coal or oil
Fuel capacity	Coal: 17–20 long tons (17–20 t); Oil: 4,000–5,000 imp gal (18,200–22,700 L; 4,800–6,000 US gal);
Water cap.	9,500–10,000 imp gal (43,000–45,000 L; 11,400–12,000 US gal)
Firebox:
• Grate area	66.7 sq ft (6.20 m2)
Boiler pressure	210 lbf/in2 (1.4 MPa)
Heating surface:
• Firebox	319 sq ft (29.6 m2)
• Tubes and flues	3,730 sq ft (347 m2)
• Total surface	4,049 sq ft (376.2 m2)
Superheater:;
• Type	Schmidt
• Heating area	810–1,087 sq ft (75.3–101.0 m2)
Cylinders	Two, outside
Cylinder size	26 in × 30 in (0.66 m × 0.76 m)
Valve gear	Inverted Walschaerts
Train heating	Steam heat
Loco brake	Independent air
Train brakes	Automatic air

Type and origin
Type and origin
Power type	Steam
Builder	Canadian Locomotive Company
Build date	1923–1924
Total produced	16 (U-1-a) 21 (U-1-b)
Rebuild date	1947 (1)
Number rebuilt	1 (No. 6001)

Canadian National U-1-a and U-1-b
Canadian National U-1-a and U-1-b
	Canadian Pacific U-1-a No. 6015 on display at Jasper, Alberta in 2000
Power type
Type and origin
Power type	Steam
Builder	Canadian Locomotive Company
Build date	1923–1924
Total produced	16 (U-1-a) 21 (U-1-b)
Rebuild date	1947 (1)
Number rebuilt	1 (No. 6001)
Configuration:;
Specifications
Configuration:;
• Whyte	4-8-2
• UIC	2′D1′ h2
Gauge	4 ft 8+1⁄2 in (1,435 mm)
Leading dia.	34+1⁄4 in (0.870 m)
Driver dia.	73 in (1.854 m)
Trailing dia.	43 in (1.092 m)
Minimum curve	16°
Wheelbase	Loco: 41 ft 9 in (12.73 m)
Length	90 ft 4+1⁄4 in (27.540 m)
Width	10 ft 9+5⁄8 in (3.292 m)
Adhesive weight	233,790–235,390 lb (106.05–106.77 tonnes)
Loco weight	355,570–355,570 lb (161.28–161.28 tonnes)
Total weight	602,600–603,870 lb (273.33–273.91 tonnes)
Fuel type	Coal or oil
Fuel capacity	Coal: 17–20 long tons (17–20 t); Oil: 4,000–5,000 imp gal (18,200–22,700 L; 4,800–6,000 US gal);
Water cap.	9,500–10,000 imp gal (43,000–45,000 L; 11,400–12,000 US gal)
Firebox:
• Grate area	66.7 sq ft (6.20 m2)
Boiler pressure	210 lbf/in2 (1.4 MPa)
Heating surface:
• Firebox	319 sq ft (29.6 m2)
• Tubes and flues	3,730 sq ft (347 m2)
• Total surface	4,049 sq ft (376.2 m2)
Superheater:;
• Type	Schmidt
• Heating area	810–1,087 sq ft (75.3–101.0 m2)
Cylinders	Two, outside
Cylinder size	26 in × 30 in (0.66 m × 0.76 m)
Valve gear	Inverted Walschaerts
Train heating	Steam heat
Loco brake	Independent air
Train brakes	Automatic air
Maximum speed
Performance figures
Maximum speed	75–95 mph (121–153 km/h)
Tractive effort	49,590 lbf (220.6 kN)
Factor of adh.	4.71 – 4.74
Operators
Career
Operators	Canadian National Railways
Power class	50%
Number in class	16 (U-1-a) 21 (U-1-b)
Numbers	6000–6015 (U-1-a) 6016–6036 (U-1-b)
Retired	1950 (6004) 1951–1962
Preserved	6015
Disposition	6015 preserved, remainder scrapped
	References for above:

Power typeSteam

BuilderCanadian Locomotive Company

Build date1923–1924

^[2]^[3] The Canadian National U-1-a and U-1-b class locomotives were two subclasses of 37 4-8-2 Mountain-type steam locomotives built for the Canadian National Railways between 1923 and 1924. They were retired between 1951 and 1962. Classes U-1-c/d/e were identical locomotives to U-1-b, built for the Grand Trunk Western. The later class U-1-f is covered elsewhere.

Table of orders and numbers
Year	Subclass	Quantity	Manufacturer	Serial Nos.	CN Nos.	Notes
1923	U-1-a	16	Canadian Locomotive Company	1696–1711	6000–6015	6015 preserved in Jasper, Alberta, since 1972
1924	U-1-b	21	Canadian Locomotive Company	1744–1758, 1764–1769	6016–6036	All scrapped

[1]

[2]

[3]

CN U-1-a and U-1-b

In art

Preservation

References

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