Buff the perk flak jacket to also apply to vehicles. In my opinion, as of right now it's not useful at all and it's really disappointing as it's the last perk you unlock for engineer. I think it should be changed so that if the driver/pilot in a vehicle has it equipped, the vehicle would take slightly less dmg from rockets, mines and any other explosions. I think this is a change we need because it would make the perk useful and give engineers more options to choose from.