Virginian 2-10-10-2 Locomotives in the USA

Class AE (Locobase 417)

Data from "Virginian 2-10-10-2 Locomotives", Railway Mechanical Engineer, Volume 92, No 11 (November 1918), pp. 600-604 and from VGN 8-1951 Locomotive Diagrams supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection. See also "New Mallet Articulated Locomotives for the Virginian Railroad", Locomotive Magazine, Volume XXV [25] (15 April 1919), pp. 54-58; James Partington, "Avoidable Waste in Locomotive Operation as Affected by Design", No. 1816, December 1921 in Transactions of the American Society of Mechanical Engineers, Volume 43 (New York: The Society, 1922), 987-1011; "Virginian Mallet Locomotives", Railway Journal, Volume 27, No 10 (October 1921), pp. 12-13. (Thanks to Chris Hohl for his 17 March 2017 email noting the original tender capacities and weights; and to Wes Barris of steamlocomotive.com for his 28 June 2018 email reporting the missing metric equivalents to cylinder diameter and stroke; and to Randal O'Toole for his 28 August 2022 email noting an incorrect citation for Partington's paper.) Works numbers were 60000-60001 in April 1918 60002 in May, 60003-60004 in June, 60005 in July, 60006 in August, 60007 in September, 60008 in October, and 60009 in November.

Firebox heating surface in the specifications included 78.5 sq ft (7.29 sq m) of arch tubes that were later removed.

These were far better proportioned engines than the Triplexes built for the Erie (Locobase 3300) or the 2-8-8-8-4 (Locobase 3301) that later entered service on the Virginian.

Their boiler and grate demand factors were within reason, which meant the crew could keep steam up, especially since the class used a Duplex or Standard mechanical stoker. A relatively short combustion chamber fleshed out the firebox heating surface area. HP cylinders received steam through 16" (406 mm) piston valves, while the massive LP cylinders, which contained a volume of 33.51 cu ft (949 liters) each, used double-ported slide valves. Simple starting TE reached 176,000 lb (79,832 kg.or 782.8 kN).

LM's 1919 report described one of the key sections of line that contributed to the design of these beasts. On the Deepwater Divisioni, the fourteen miles (22.5 km) between Elmore and Clark's Gap consisted of 2 1/2 miles (4 km) of 0.5% grade, followed by a climb of 11.5 miles (18.5 km) up the 2.07% ruling grade. This "crucial part of the entire system" over which "all of the east-bound tonnage passed" was entirely single-tracked and included five tunnels. A true chokepoint that demanded unstoppable power.

Estimating Engineer James Partington of Alco delivered a paper in December 1921 in which he described the pulling power of one of these double decapods. One pulled a 15,725-ton (14,295 tonne) train from Princeton, Va. to Roanoke burning 26.9 lb of coal per 1,000 ton-miles (7.58 kg per 1,000 km). Another 2-10-10-2 managed 110 cars or 17,250 tons (15,680 tonnes) over a ruling adverse grade of 0.2%.

Eric Bott's 3 February 2019 email questioned Locobase 417's tender coal capacity which was given as 20 tons; Locobase found that he hadn't revised the figures after Chris Hohl's earlier corrections. A recheck of the 1918 RME article and other sources showed the original coal amount as 12 tons. Later, a larger tender weighing 231,000 lb (104,780 kg) loaded used tender boards to increase the coal bunker's capacity, raising it to 20 tons (18.2 metric tons) of coal. In that configuration, the tender increased the overall power system weight to 915,000 lb (415,038 kg).

The AEs performed well for 30 years, first as pushers for the 2.11% grade at Elmore until replaced by electric engines, later as helpers on other grades. EW King, Jr (in Drury, 1993) notes that except for the addition of Worthington BL feedwater heaters, these engines were never modified.