Hull Integrity

Image from Reddit - a ship status icon, showing hull integrity of 11% with intact shield.

Hull Integrity is a feature of every ship or SRV. All ship will have a hull percentage, hull bar are show between speedometer and Power Distributor pip HUD. Every ship will come equiped with a Shield Generator, protect them from damages. Once the shield is down, hull will be vulnerable from every damage sources, and the ship will be destroyed if the hull reaches 0%. They can rebuy their ship when their ship is destroyed, with a cost.

They are not yet invulnerable in Supercruise, as overheating can still kill you in Supercruise. Heat can be acquired in Supercruise by stop your ship near a star, it will gaining heats, so don't think you could survive by activating your FSD. With passengers on the ship, when your ship taking enough damage, a passenger will broadcast a message on the Inbox, inform that they are too scare of death and requiring their carrier to stop taking damage.