Boston & Albany / New York Central 2-6-6-2 "Mallet Mogul" Locomotives in the USA

Class N-1 (Locobase 11081)

Data from "Mallet Articulated Compound Locomotive, 2-6-6-2 Type" American Engineer and Railroad Journal (April 1910 ), pp. 135-137. Works number was 46714 in January 1910.

Moving up from Consolidations, with four axles of power, to Mallets in the Berkshires only made sense, according to the report in the AERJ. The territory was "...country where heavy grades combined with sharp curves are practically continuous. There are several long sections where grades of approximately one percent are encountered and eastbound, the section of six miles between Pittsfield and Hinsdale is on a grade of 1.42 percent. Westbound a grade of 1.5 per cent 11.5 miles long is found between Chester and Washington, Mass."

To determine if a Mallet was the answer, the New York Central ordered this prototype. The AERJ writer noted that the relatively small grate was chosen to better fit the demands of slow-speed service in compounds burning bituminous coal. In most other respects, except for the larger boiler and the larger truck wheels, the N-1 was "practically duplicate in design to eight recently delivered by the same builders to the Denver & Rio Grande Railway." (See Locobase 294 for the superheated upgrade of the D & RGW L-62.)

Class N-2b, NE-2c, NE-2e (Locobase 11082)

Data from NYC 8 - 1917 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 52283-52286 in December 1912, 55681-55684 in March 1916, 56707-56709 in March 1917, and 56710-56711 in April.

Once the NYC had committed to buying superheated versions of the B & A's NB-1a (Locobase 11081), the B & A began procuring its own batch. Like the Central's 1374 (Locobase 16284), thirteen had the 10" (254 mm) piston valves for its HP cylinders and a firebox of relatively small area.

Class NE-1a (Locobase 16284)

Data from NYC 8 - 1917 Guide to Dimensions and Classifications of Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 26 May 2017 email noting the superheated version of the N-1. Locobase had included 1374 in the NE-2a entry at Locobase 5583, but a reexamination of the information showed significant differences between 1374 and the others. Hohl's 8 February 2019 email noted the boiler pressure change and the correct adhesion and engine weight.)

This locomotive originally appeared as the saturated-boiler N-1 described in Locobase 11081. Chris Hohl noted that the NYC increased boiler pressure to 210 psi by 1917

Fred B Furminger, Associate Editor of the New York Central Railroad System Historical Society's Central Headlight, contacted Wes Barris of steamlocomotive.com in March 2010 to correct the entry Barris and Locobase then presented. Locobase gratefully includes the following quotation of Furminger's communications:

"[1249] was immediately put into service on the Albany and Springfield in the Berkshire Hills for exhaustive testing. After testing was completed, it was sent back to Alco at Schenectady for the addition of a superheater and a security brick arch to improve performance, efficiency and economy. HP cylinders were served by 10" (254 mm) piston valves; double-ported slide valves served the LP cylinders.

"By April 1911 it was transferred over to the New York Central & Hudson River, reclassified as an NE-1a, renumbered to #1374 and sent to the NYC Lines Pennsylvania Division where additional testing took place."

"The objective on the Pennsylvania Division was also to obtain a locomotive capable of handling a 70 car train at an average speed of 10 to 14 miles an hour without assistance. The alternative was to double track the railroad to get the increased capacity the traffic required.

"These tests proved so successful that an additional 74 of these mallets in the NE-2 class with sub-classes a through g were added through 1921 for use on the B&A and NYC&HR. [See Locobase 11082 for the B&A production variant, Locobases 16136, 4794, and 16135 for the New York Central's engines.]

"So the first NYC/B&A 2-6-6-2 was not classified as NB-1a. That class was an 0-6-6-0. It should be classified as N-1 and the number should be #1249, not #1374. It was not #1374 until it was reclassified as an NE-1a when it was moved over to the NYC&HR in 1911."

Furminger adds, bibliographically: "The above information was gathered from "Steam Locomotives of the New York Central Lines, Vol. 1, Parts > 1&2 NYC&HR and B&A" by Edson and Vail and "New York Central's Later Power 1910-1968" by Alvin Staufer and Edward L. May.

Class NE-2a (Locobase 5583)

Data from the 1926 guide to Dimensions and Classifications of Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Test of a Mallet Locomotive Equipped with Superheater and Brick Arch," American Engineer & Railroad Journal (December 1911), pp. 471-474; and "Maintaining Mallet Locomotives," American Engineer, Vol 86, No 7 (July 1912), pp. 335-337. (Thanks to Chris Hohl for his 2 July 2015 email correcting the ranges of road numbers for each subclass.) Works numbers were 49556-49579 in April 1911 59580 in May

Used in coal hauling in the Pennsylvania Division on secondary lines for coal trains where axle loadings didn't permit heavier engines. Tests of the 1249 (see Locobase 11081 for details of the tests) over a division that "required a wider range of operation conditions" led the committee supervising those tests to return the Mallet to Schenectady to be fitted with a Schmidt superheater, a Security brick arch, and 10" (254 mm) piston valves for the HP cylinders and double-ported slide valves for the HP cylinders.

These made the difference and the Central ordered 25 more. The latter 25 used 12" (305 mm) piston valves and had more firebox heating surface area in the form of 27 sq ft (2.51 sq m) of arch tubes. The combined cylinder volume also grew as each of four cylinder diameters increased by 1" (25.4 mm).

Once the class was delivered to the NYC, the AERJ reported that they were "handling the traffic on this division which had previously required 60 Consolidations." Since each engine was credited with a 35% fuel savings per ton mile, the AERJ calculated that 54% more ton-miles per ton of coal was obtained by the Mallet compared to a Consolidation.

In its July 1912 update, The AERJ reported the results of the first year of service: "On the test, the Mallet locomotive handled 3,461 tons behind the tender at 15 miles per hour and 3,734 tons at 12 1/2 miles per hour. After one year's continuous service all of the locomotives are handling an equal tonnage at speeds as good as or better than those obtained in the test. They are doing this easily and to the complete satisfaction of all concerned. The fuel and water consumption is practically the same as was obtained on the tests which required .084 Ibs. of coal per tonmile at 15 miles per hour. This was practically 40 per cent, less than was required by either of the consolidation locomotives at the same speed."

The AE writer attributed the locomotives' "This continued excellent service" to three factors: "[T] hey were properly designed for the conditions ...they were well built, and, most of all, ...they are being properly taken care of at the terminals."

Obviously pleased to have developed the right horse for this particular course, the Central nevertheless waited more than six years to take delivery the next batch of 25, in which the superheater grew at the cost of a small deduction of fire tubes; see Locobase 4794). Ten more completed the class in 1920-1921 (Locobase 16135).

All NE-2a were scrapped in 1932-1934.

Class NE-2d, f (Locobase 4794)

Data from the 1930 guide to Dimensions and Classifications of Locomotives seen on [] (May 2003). (Thanks to Chris Hohl for his 2 July 2015 email correcting the ranges of road numbers for each subclass.) Works numbers were 56687-56706 in February 1917, 56860-56861 in November, 56862-56864 in December.

Used in coal hauling in the Pennsylvania Division on secondary lines for coal trains where axle loadings didn't permit heavier engines. Locobases 11081 and 16136 describe the first set of Mallets designed for this service.

They were a considerable success, leading to an order for 25 more for delivery in 1917. Changes were small, but included a rearrangement of tubes and flues in which three flues were deleted in favor of four flues. This gained the design about additional 80 sq ft of superheater area. The new tenders carried two more tons of coal.

Nineteen were scrapped in 1932-1934 with 1371-1372 leading the parade in April 1932. 1354, 1355, 1357, 1358, 1361 and 1373 were renumbered in 1936 to 1933-1938. Some remained in service until the early 1950s.

Class NE-2g (Locobase 16135)

Data from the 1926 guide to Dimensions and Classifications of Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also [] . (Thanks to Chris Hohl for his 2 July 2015 email correcting the ranges of road numbers for each subclass and for his 5 July 2017 email reporting 1342's larger tender.) Works numbers were 62358-62359 in December 1920, 62360-62367 in January 1921.

Used in coal hauling in the Pennsylvania Division on secondary lines for coal trains where axle loadings didn't permit heavier engines.

The last ten came in 1920-1921. Power dimensions and heating surface areas were unchanged from the 1917 batch (Locobase 4794). Total engine weight increased by less than five tons, adhesion weight by about one ton.

Tender weight and capacity grew substantially. Chris Hohl found that engine 1342 trailed, at least for a time, a much larger tender than the others. It weighed 118,500 lb (53,751 kg) empty and 291,500 lb (132,222 kg) when loaded with 15,000 US gallons (56,775 litres) of water and 24 tons (21.8 metric tons) of coal.

This last batch served through World War II before being scrapped in 1949 and 1952.