An aircraft noise calculation model uses a database of aircraft noise and performance signatures and an air traffic prediction together with an algorithm to predict the noise pollution at points on the ground. Each aircraft category has an acoustic and a flight operational data set in the database. The acoustic data describes the sound-emission properties of the aircraft and the operational data describes the performance characteristics of the aircraft during takeoff and landing to generate an altitude and speed profile for the flight path. From this flight trajectory the distance between the aircraft and the point of interest on the ground is computed. The air traffic data is a geometric description of the takeoff and landing flight tracks and an allocation of the individual aircraft types to these flight tracks.
The computations can use either a conventional (i.e. simplified) method or a scientific simulation method such as the SIMUL model developed by the aircraft noise group. The scientific simulations with the SIMUL model deliver a significantly more accurate prediction, but need a more detailed database. The information required for the database is often unavailable, or expensive to produce, and for this reason the conventional methods are used for most practical noise predictions (“Best Practice Models”).