As a matter of fact, you can drive away in most of the Soviet tanks sitting on static display since 1945.
In order to fly a Mi-24 helicopter sitting a couple years without maintenance you only need to pour water into batteries.
Then why were the Ukrainians dropping their choppers at such an alarming rate due to poor maintenance during the UNTAC mission the UN finally grounded them and brought in Canadian Bells? I’m not convinced the Ukrainians ever flew entirely sober, either. And they did really stupid stuff, too, like dunk a Mi17 in the bay while trying to copy the cool way the French Pumas took off — a maneuver those old Mi-17s were not capable of performing.
Sorry, I visited Russian garrisons and saw for myself demoralized soldiers painting the rotten tires of their vehicles black before some bigwig was due to arrive. As you can imagine, these soldiers were not amused. Granted, this was over 20 years ago when the Russian army was perhaps at its lowest point. I somehow doubt the Ukrainians’ old Soviet junk is in better shape now than it was then, though.