The Alerts API offers push-based alerting of flight status information. Alerts are based on flight segments and can be triggered on a variety of conditions and status changes. The API allows you to create, retrieve, and delete Alert rules.
To use the Alerts API, the developer must implement a web service that accepts an HTTP POST and parses an Alerts Message, then set up a rule specifying that service as the destination. When an alert is triggered based on flight status and an active rule, FlightStats sends a message to the destination.
To learn more visit the Alerts API Documentation. Events that can trigger an alert are described here.