Bird Strike
A collision with birds, most often during takeoff or approach, and most dangerous when it takes out more than one engine.
Engines and windshields are certified against bird impact up to defined weights, so most strikes cause damage rather than an accident. The severe cases involve large birds, flocks, or ingestion into every engine at low altitude, where there is neither height nor time to trade.
Findings typically extend to airport wildlife management as much as to the aircraft.