Greater success than the Santa Fe Class 3000 was the Virginian Class AE, which a few years later was also built exactly ten times. It was about 70,000 pounds heavier and was factory built as a Mallet locomotive. To avoid the problems of an overly long boiler, the boiler was designed with the largest possible diameter and moderate length to get better proportions. With a diameter of almost ten feet, it is considered the widest locomotive boiler of all time. The low-pressure cylinders also set new standards with a diameter of 48 inches and a volume of nearly 58.000 cubic inches each.

At just over 135.000 pounds, the normal starting tractive effort in compound operation already reached a very impressive value. Like many Mallet locomotives, the AE also had a special starting valve that made it possible to direct the live steam into the low-pressure cylinders if the wheels were in an unfavorable position. This resulted in a starting tractive effort of 162.000 pounds using the calculation method used in Anglo-American countries.

Schematic drawing with dimensions

Locomotive Magazine, April 1919

Due to the dimensions of the locomotives, it was necessary to deliver them without a driver's cab and low-pressure cylinders and only to assemble them in the area of operation, where operation of the locomotives without colliding with obstacles on the track was guaranteed. A relatively short variant was selected as the tender so that existing turntables could also be used. Although these locomotives also had to struggle with steam production as the speed increased, they are considered to be more successful than the ATSF 3000. They were mostly used as pusher locomotives for heavy coal trains, which often only moved at around 8 mph at the ramps and did not overload the boiler of the AE. There are also reports of locomotives pulling trains weighing over 17,000 tons alone. They remained in service for almost 30 years and were eventually replaced on the steepest inclines by electric locomotives.

Four years after the delivery of the first class H-8 Allegheny locomotives to the Chesapeake & Ohio, the Virginian ordered eight units, which differed little from their prototype. Both classes can therefore be described as the most powerful steam locomotives of all time, which required a three-axle trailing bogie due to their extraordinarily large firebox. Since the C&O had named their locomotives after the mountain range to be crossed, the Virginian's locomotives were named after the Blue Ridge Mountains. External distinguishing features were only the slightly lower sand domes and other proportions on the tender. The AG was also manufactured near Lima in Ohio.

When the engines were delivered, the Virginian had major problems because the Chesapeake & Ohio did not want any other locomotives with such a high axle load to run on their own network. According to rumors, the C&O itself was not aware of the high axle load of the H-8, as this had been increased several times during development. This subsequently led to the inspection of all affected bridges and cost Lima several million dollars. Later, however, the locomotives adapted for the Virginian were again used as the basis for a second delivery to the C&O in 1948. At the Virginian, the machines were already retired by 1955 and scrapped by 1960.

Two years after Baldwin had delivered the class P-1 triplex locomotives to the Erie, another one was delivered to the Virginian. This locomotive got the number 700 and was designated class XA. In general it had a similar layout, but a two-axle trailing truck under the tender.

So like the P-1, it had six cylinders of the same size, although these were smaller than those of the predecessor to reduce the steam consumption. The middle ones served as high-pressure cylinders. The exhaust steam of the right one fed both front low-pressure cylinders, while the left one fed the two rear ones. Also here the exhaust steam of the rear cylinders was used for a feed water heater in the tender, what in turn reduced the draft in the boiler and thus hindered the steam production.

In the result, its performances were similar to those of the P-1. The maximum speed at which the locomotive could utilize its full power was 5 mph. After only three years of operation with continuous efforts by Baldwin employees to remedy its problems, it was returned to its builder. There its parts were used to create a 2-8-8-0 Mallet of the class AF and a Mikado of the class MD.