Emergencies

Emergencies were introduced in Alpha 36, which also brought fences, ground and air animals, bird strike prevention systems (BSPSs), hangars, airport police stations, emergency response stations, police cars, ambulances, fire trucks

Basics
Emergencies will only start occurring if:


 * The game has been running for at least a few in-game hours


 * The commercial license has been researched

Some emergencies need handling while others just require you to wait a certain amount of time.