NMSim

NMSim is a powerful noise model simulation tool which computes 3-dimensional, in-flight or en-route spectral noise energy for a wide variety of noise sources.

Traditional aircraft noise models are integrated and they work from a database of sound exposure levels (SELs) from complete flyovers and are directed toward time-integrated noise metrics such as the Day Night Average Sound Level (DNL) and equivalent levels (Leq).

NMSim uses a more elaborate modeling approach in which the actual time history of noise is computed at each receiver location. Because it computes noise in terms of the complete, spectral time history, it can be used to analyze the data in A-weighted sound pressure levels or any other metric needed for the application.