Austrian Southern 0-6-2 Locomotives in Austria

Class Engerth (Locobase 544)

After the chains and articulation of the four Semmering trials locomotives proved too complicated to provide mountain power, the Austrian Southern tested William Engerth's coupled-tender design. Engerth patented a locomotive that had drove the tender axles through 3 cogs, 2 arranged as a pair under the tender pivot, a third that could be moved to one side to disengage the cog drive. Thus the locomotive used the additional weight of the tender as well as the driven axles in addition to the 3 axles that were driven by conventional main rods from pistons.

The first 26 engines were built by the Esslingen Engine Works and John Cockerill. The spur drive was soon discarded as difficult to keep in running order, but the tender's contribution to adhesive weight caused the Engerth design to be adopted in several countries. 50 AS Engerths without cog drive were built for the Austrian Southern from 1857 on. Some had 50-in drivers for freight, others used 54-in drivers for passenger trains.

The design enjoyed short-lived favor. Although the tenders did increase adhesive weight, they were too intimately connected with the engine. The pivot and guide plates wore excessively and righting the engine after a derailment was complicated by the difficulty in detaching the tender. Some of the Austrian engines were converted to more conventional 4-coupled engines.