Even for Soviet Russia, this vehicle is weird. This is a BWSM 80, which sounds perilously close to something your Mom would be into, but was in fact a prototype Soviet design that fused a GAZ 53 truck with a DT 75 bulldozer to create… whatever the hell this is.
In normal use the BWSM 80 operated as per a regular truck, albeit one with a track system suspended between the wheels. However in extreme conditions the BWSM could lower the track system thus raising its wheels off the ground, and thereby becoming a skid-steer tracked vehicle in the process. If, as we were, you’re struggling to figure that out, take a look at the video below!
That video, and the creation within it, comes from previous bloggee (and apparent Technic wizard) Samolot of Eurobricks, who has recreated the Russian prototype in brilliantly-functional remote control Technic form.
Two Power Functions L Motors drive both the wheels and the tracks, with some ingenious decoupling mechanism we’re struggling to fathom dividing the power appropriately between the two. A Medium Motor drives the lifting mechanism to deploy the tracks, which also feature suspension, and there are LED headlights up front too.
There’s much more of Samolot’s wonderfully odd creation to see at the Eurobricks discussion forum via the link above, or you could just watch that amazing video again!