A great team of constructors worked at the project of this distinguished tractor-trailer which would later become legendary. They worked at a full swing and in 1935 all the technical ducumentation was finished.

The core of the trailer was the tank engine. In 1936 two copies of the machine were built and tested for 2 years. It was called “Voroshylovets” in the honor to marshal Voroshylov.The trailer impressed the higher ranks a lot and was approved.

As the machine was long enough it was easy to place the engine under the cabin which give the advantage to the construction。 The trailer was very reliable in operation, however the transmision was a little bit half-baked as the engineers only started to accomodate themselves to powerful and tough diesel engine.

The tracks installed had low traction especially on icy roads and were difficult to clear of snow – that's why the trailer couldn't realize all it's power potential.

The electric accessories system was very rich: 24V generator, 4 accumulators, full lighting device kit and the alarm system.

 A removable tarpaulin awing protected the carried coods.

“Voroshylovets” had the average speed of 18 km/h and could make a 24 hour march without refuelling.  Its cruising range was 390 km without a trailer and about 240 km with one.

Unfortunately there were some shortcomings – the construction of tracks made the operation on snowy routes very hard. Also the failure of the main clutch was no rare after 200 -300 operation hours. The drivers aknowledged that the winch was inconvenient to use. All these and some other drawbacks were aggravated by unavailability of the mechanisms and spare parts for repair in the very military units.

1123 such machines were manufactured by 1941 and the army was still in want of this equipment. 

“Voroshylovets” was used at every front during WW2 despite its drawbacks – the soldiers were proud of the trailer and appreciated it highly.  During the war the machine had hard times as less and less spare parts were produced and they were doomed to be abandoned in almost good order.

Those tractor trailers which remained after the Great war were used for some years to tow heavy artillery equipment.

Starting from 1942 Ya-12 trailer was being developed by Soviet engineers. This piece of machinery used to tow light artillery equipment.

Ya-12 demonstrated great dynamics, smoothness, reliability and good speed. These trucks were in the army till the 50-ies.