Burn
Pilots need to worry about more than just bullet holes on the battlefield. Some weapons deal Burn (damage over time). Burn might represent flames, searing plasma, acid or something more insidious, like a swarm of greywash nanites.
When characters take Burn, it has two effects: first, they immediately take Burn Damage, ignoring Armor, and then they mark down the Burn they just took on their sheet. At the end of their turn, characters with Burn marked must roll an Engineering check. On a success, they clear all Burn currently marked; otherwise, they take burn damage equal to the amount of burn currently marked.
Burn from additional sources adds to the total marked Burn, so a character that is hit by two separate 2 Burn attacks first takes 4 Burn damage (2 from each attack), then marks down 4 Burn (again, 2 from each attack). At the end of their turn, that character makes an Engineering check, failing and taking an additional 4 Burn damage. Next turn, the same character gets hit by another 2 Burn attack. They take 2 Burn damage, then mark the extra Burn down (now it’s 6!). At the end of their turn, they must succeed on another Engineering check or take 6 Burn more damage. Fortunately they pass, clearing all burn