Former Chesapeake & Ohio No. 1309 on the Western Maryland Scenic Railroad in Ridgeley, West Virginia, on December 17, 2022.
(Ynot3700, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)
USRA 2-6-6-2 MALLET STEAM LOCOMOTIVE
The USRA 2-6-6-2 is a standardized design of 2-6-6-2 Mallet locomotives developed by the United States Railroad Administration during World War I.
USRA 2-6-6-2 Wheel Arrangement diagram. Front of locomotive on left.
(Gwernol, Public domain, via Wikimedia Commons)
Design
The USRA 2-6-6-2 locomotive is a Mallet, or compound articulated type, having both low-pressure and high-pressure cylinders. The smaller high-pressure cylinders powered the rear set of driving wheels, and the larger low-pressure cylinders powered the forward set of driving wheels. The USRA 2-6-6-2 articulated locomotives were direct developments of the Chesapeake & Ohio class H2 and H4 series.
Orders
During the tenure of the USRA, 30 of these articulated steam locomotives were built. The Chesapeake and Ohio Railway (875-894, later 1520-1539) and Wheeling and Lake Erie Railway (8001-8010) ordered the USRA 2-6-6-2 Mallet. The first Mallet was delivered to the W&LE in 1919 for $71,966.94. Later, the Nickel Plate Road (NKP) leased them from the W&LE, renumbering them for use on its rails. The independently pivoted front engine allowed it to negotiate branch lines and tight curves while hauling larger consists than its smaller cousins in the USRA series.
The Chesapeake & Ohio Railroad ordered the first of these compact 2-6-6-2 articulated steam locomotives from Alco in 1911. It was a massive locomotive for the time, and it performed well enough for the C&O to order additional, but slightly modified, versions right through 1923. These locomotives were designed to replace the 2-8-0 Consolidations for the coal drags on the C&O's Hinton Division. The 2-6-6-2s could handle more tonnage than the double-headed pair of 2-8-0s they replaced, and they burned less coal in the process. The 2-6-6-2s proved to be ideal mine run engines as their power and flexibility plus low weight on drivers made them ideal for the curving and heavily graded branches in the mountains of Virginia and West Virginia.
An additional ten (10) locomotives were built in 1949. These C&O Class H6 2-6-6-2s, numbered 1300 to 1309, were the last steam locomotives produced by Baldwin for use in the United States. The last of these were retired in 1957. Most of the locomotives were scrapped, but the last two produced were retained by C&O as examples of their steam heritage. The C&O 1308 is in the care of the Collis P. Huntingdon Chapter of the National Railway Historical Society at Huntington, West Virginia, while the C&O 1309 was restored to operation on December 31, 2020, at the Western Maryland Scenic Railroad in Cumberland, Maryland.
USRA 2-6-6-2
Type and origin
Power type: Steam
Builders: Baldwin (10), Alco (20)
Build dates: from 1911 to about 1940
Total produced: 30
Specifications
Configuration:
• Whyte 2-6-6-2
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Driver diameter: 56+1⁄4 in (1,429 mm)
Trailing diameter: 45 in (1,143 mm)
Adhesive weight: 376,500 lb (170,800 kg)
Locomotive weight: 449,000 lb (204,000 kg)
Boiler pressure: 210 psi (1.45 MPa)
Cylinders: four, two LP (front), two HP (rear)
High-pressure cylinder: 22 in × 32 in (559 mm × 813 mm)
Low-pressure cylinder: 35 in × 32 in (889 mm × 813 mm)
Performance figures
Tractive effort: 77,900 lbf (347 kN)
C&O Class H6
Type and origin
Only specifications that differ from left are shown.
Builder: Baldwin
Serial number: 74269–74278
Build date: 1949
Total produced: 10
Specifications
Driver diameter: 56 in (1,422 mm)
Trailing diameter: 44 in (1,118 mm)
Adhesive weight: 366,700 lb (166,300 kg)
Locomotive weight: 434,900 lb (197,300 kg)
Career
Operators: C&O
Class: H6
Numbers: 1300–1309
Retired: 1957
Disposition: 2 preserved
C&O 1308
C&O 1309