FlightAware API
FlightAware (flightaware.com) has 3 public methods: list airport arrivals or departures, get airport delays and check flight status. Each costs 1 credit per completed run (1¢ with pay as you go); failed runs are free.
Unofficial. Not affiliated with or endorsed by FlightAware.
Methods
3Lists the public arrivals or departures FlightAware shows for an airport (name, city, IATA/ICAO code or FlightAware link), with flight times and status. For a city with several airports it picks the busiest listed one and says so; the public board shows up to 20 flights per direction.
Returns airport name and code, selection note; per flight: number, airline, city, airport code, aircraft, scheduled and latest time, status, link
Readflightaware.com/list_airport_flightsChecks today's delayed and cancelled departures and arrivals at an airport on FlightAware, with current weather and any reported FAA delay status. Delay averages and ground programs are returned only when FlightAware shows them; counts can be null when no statistics row is displayed.
Returns airport name and code, date, delayed and cancelled departure and arrival counts and percents, average delays, FAA ground program and reason, weather, temperature, wind, FlightAware link
Readflightaware.com/get_airport_delaysChecks the public FlightAware status of an airline flight (airline name or code plus number) on a departure date, by default today at the departure airport: airports, scheduled, estimated and actual gate times in local time, delays, gates, terminals, aircraft and distance. A date older than FlightAware's public two-week list is looked up on the flight's history page when FlightAware still shows it.
Returns flight number, airline, status, origin and destination airports, scheduled/estimated/actual departure and arrival, delays, terminals, gates, aircraft type, route distance, FlightAware link and flight ID
Readflightaware.com/check_flight_status