Tank crewmen under fire can't just step outside for relief. They have to keep their, uh, waste inside their tanks. But that may change, thanks to a patent filed by Aleksandr Georgievich Semenov:
Here's how the patent describes the scene, with numbers referring to specific items in the drawing:
"A military man (3) puts the wastes (8) into the capacity (7) directly (fig.1) or in two steps. After it's complete or, if it is necessary, incomplete filling the capacity is tightly sealed by the cover."
The key action is in one sentence: "The gun charged with special projectile is targeted on a safety zone or on any enemy target which is worth for catching it."
As the projectile leaves the tank, it removes what would eventually have become a source of stinking misery for the poor soldiers who, in combat, could be forced to remain sealed inside their vehicle for several days