Evaluation of aircraft performance algorithms in Federal Aviation Administration's Integrated Noise Model

Abstract

The Integrated Noise Model (INM) has been the Federal Aviation Administration's (FAA) standard tool since 1978 for determining the predicted noise impact in the vicinity of airports. A review of the aircraft performance algorithms in the INM was conducted and improved models for true airspeed, takeoff/climb thrust, level-flight thrust, and climb performance were developed. The true airspeed model with air compressibility correction provides an accurate prediction over a wide range of operating conditions. The quadratic takeoff/climb thrust model as a function of Mach number, altitude, and temperature and the level-flight thrust model derived from the minimum-thrust-flight condition provide an accurate prediction within considered airspeed and altitude range. The climb models for constant equivalent/calibrated airspeed as well as constant climb rate climbs introduce the flight path angle correction factor as a function of altitude, airspeed, and temperature as opposed to constant correction factor used in INM. Comparison of flight profiles predicted by the proposed methods and INM with the flight profiles provided by the Delta Airlines shows that the errors in overall ground distance traversed as well as noise contour shapes are reduced by implementing the proposed models.