If you're morbid, you might've wondered what would happen if a pro sports team was on a flight to a game ... it CRASHED... and everyone on board DIED. Believe it or not, every pro sports league has a contingency plan for that.
The plans are all called DISASTER DRAFTS. They would let the franchise immediately rebuild by drafting players off other teams.
Major League Baseball: If at least five active members of a major league baseball team die or are dismembered, the team can draft players off other teams. Each other team has to make five players available, and can only lose one player at most.
The NFL: If a team loses less than 15 players, they don't get to draft... unless the quarterback is one of them. Then they get to poach two backup quarterbacks off other teams... but those QBs go BACK to their original teams after the season.
If a team loses more than 15 players, the commissioner can cancel their games for the season. They'd automatically get the first pick in the next college draft, and get to select bench players off the other teams.
The NBA: If five or more players die or are dismembered, the team will get to draft off other teams. Each team can only protect five players... so some pretty good players would be available.