I concur with Monster Zero. That's about all he'd be able to stick out of that tiny little hatch! I've also seen photos of just that. Soviets liked to train hatch closed (like on the Abrams, but not the M60's) and parade hatch open. SO if the tank is training or in combat, the driver (and loader) would be down. The TC would be anywhere from waist to head defilade, depending on his hatch position and sense of danger.
Ron.