Adding Battlefield-esque vehicle disabling to tanks and helicopters would make for another layer of fun to both attacking a tank/ heli or being inside of it. The idea would be that, instead of a tank/helicopter going straight to zero health upon a fatal rocket blast, the vehicle would enter a "disabled" state where control of the vehicle is no longer possible due to the damage and its destruction is imminent. This could make for interesting emergent gameplay as the attacking party scrambles to kill the tank's occupants before they escape and as the vehicle party attempts to bail before the vehicle explodes with them inside of it. For helicopters, the helicopter beginning to spin out of control and blow up upon collision with terrain could make for some very cinematic gameplay as well as being emergent fun for both parties involved as the crew scrambles to jump and parachute out of the FUBAR'd helicopter and as the Engineer that shot it down watches as it spins out of control and crashes into the ground.