The standard methodology used in traditional integrated aircraft noise models has recently been revised by ICAO, based on the recommendations in ECAC Doc 29, 3rd edition from 2005 . The interim method for lateral attenuation proposed by SAE in 1981  was thereby in use for 24 years! The basics behind the methodology remain unchanged over the last 30 years. The computation tools based on this provide reliable results for long term equivalent noise levels, such as DENL and DNL. However they may fail to predict good results for single operations.There is a demand for modeling tools that can provide results that reflect changes in aircraft configuration to a larger extent than what is possible with existing tools and aircraft database. This will require more accurate description of the noise sources, better description of aircraft configuration and the ability to take meteorology into account through more sophisticated propagation routines.