Soviet Railways series Э^мх3 (Ye^mkh3)

After Lomonosov already had two different diesel locomotives with electric power transmission built, he also ordered a third one to be built with a different type of power transmission for comparison. The hydrostatic transmission that was actually planned was not yet ready for use. The result was and is still the first and only large diesel locomotive in history with a mechanical gearbox. It went into operation as Ю^m005 (Yu^m005) and was renamed Э^мх3 (Ye^mkh3).

The chassis consisted of five axles driven by coupling rods and a one-axle and two-axle bogie at each end. The engine came from MAN and was the same as in the Э^эл2. Here, however, it was designed to be reversible, since the transmission did not have a reverse gear. It had three gears which were shifted via a magnetically operated friction clutch.

Although the locomotive achieved a very high level of efficiency of just over 30 percent, the power transmission was not without problems. In addition to jerky loads on the clutches, there were also broken gear wheels. Engine power was soon reduced from 1,200 to 1,050 hp. But even this did not solve the problems, so that the locomotive was soon withdrawn and the diesel-electric competitors prevailed.