In early 2001, the US Federal Aviation Administration embarked on a multi-year effort to develop a new computer model, the System for assessing Aviation’s Global Emissions (SAGE). Currently at Version 1.5, the basic use of the model has centered on the development of yearly global inventories of commercial aircraft fuel burn and emissions of various pollutants to serve as the basis for scenario modeling. This paper describes the algorithms and data used in the model as well as the results from initial validation assessments. SAGE results indicate that global fuel burn and nitrogen oxide (NOx) emissions decreased by over 6% from 2000 to 2001 (fuel burn and NOx), and then steadily increased to over 12% (fuel burn) and 15.5% (NOx) above 2000 levels in 2005. Comparisons to the results from previous studies have shown that SAGE tends to agree more closely with fuel burn and NOx than with CO and HC. Validation assessments have shown that SAGE can predict per flight fuel burn to within 3% on an average basis with no apparent bias, when compared to about 60,000 flight’s worth of data from a major US airline and about 20,000 flight’s worth of data from two major Japanese airlines.

System for assessing Aviation's Global Emissions (SAGE), Part 1: Model description and inventory results

Aircraft noise prediction

Quite a number of numerical computation works contributed to the atmospheric acoustic propagation emerging constantly in recent years make the formation of a new developing sub-branch "Computational Atmospheric Acoustics" become just round the corner. The present paper provides a brief, clear, systematic and comprehensive introduction to this brand-new field and gives a relatively exhaustive demonstration of its main objects and methods, especially the parabolic equation (PE) method, the fast field program (FFP) and the Gaussian beam (GB) approach-may be regarded as a modified ray tracing procedure. A discussion concerning the comparison among the results obtained by these various methods cannot be included for the limitation of space, some opportunity for publishing these interesting materials separately would be expected.

Computational atmospheric acoustics

This paper provides an analysis of the BADA aircraft performance model capabilities and addresses the BADA model ability to provide accurate modeling of aircraft performances over the complete flight envelope for a number of aircraft types and different ways in which an aircraft can be operated during the flight. The focus of the paper is the support of complex aircraft operations by BADA. A short description of the two existing BADA families and their main characteristics is given. The complex flight instructions and operating regimes — economy climb, cruise and descent based on cost index, maximum range cruise, long range cruise, optimum altitude and maximum endurance cruise — identified as key features in support to optimized flight execution are discussed. The optimization procedures and equations in which they derive are presented and the ability of the BADA model to support these flight operations is demonstrated. It is shown that BADA 4 can be successfully used with complex instructions and operating regimes, whereas the use of BADA 3 is limited. Finally, the results of a validation experiment dedicated to BADA thrust models are presented.

Advanced aircraft performance modeling for ATM: Analysis of BADA model capabilities

This paper describes an optimisation study concerning arrival trajectories that has been conducted using a recently developed tool for the analysis and design of noise abatement procedures around airports. This new tool combines a noise model, a geographic information system, and a dynamic trajectory optimisation algorithm. The optimisation algorithm generates routings and flight-paths that minimise the noise impact in the residential communities surrounding the airport, while satisfying all imposed operational and safety constraints. The study on arrival trajectories presented herein complements an earlier study involving departure trajectories. Although the numerical results shown pertain to a particular example airport, viz Amsterdam Airport Schiphol, the study actually focuses on the development of a generic methodology that could be applied to any given airport. The results clearly demonstrate the effectiveness and flexibility of the developed tool.

Optimisation of noise abatement arrival trajectories

The Federal Aviation Administration, Office of Environment and Energy (FAA, AEE-100) has developed Version 7.0 of the Integrated Noise Model (INM) with support from the John A. Volpe National Transportation Systems Center, Acoustics Facility (Volpe Center) for development of the acoustic computation module, and from the ATAC Corporation for systems integration, development of the graphical interface, and methods for computing aircraft flight profiles and constructing flight paths, which are processed by the acoustics module. This Technical Manual describes the core technical components in INM Version 7.0, including the flight-path methodology (Chapter 2), along with the basic methodology employed by the INM to compute noise levels or time-based metrics at a single, user-specified observer, or at an evenly-spaced, regular grid of observers (Chapter 3). The noise/time computation methodology includes a description of: (1) computation of the flight-segment geometric and physical parameters; (2) flight-segment noise-level interpolation process; (3) atmospheric absorption adjustment; (4) acoustic impedance adjustment; (5) flight-segment noise-fraction adjustment for exposure-based metrics; (6) aircraft speed adjustment for exposure-based metrics; (7) updated lateral attenuation adjustment; (8) ground-based directivity adjustment for observers behind start-of-takeoff-roll, as well as for computing metrics associated with run-up operations; (9) new helicopter noise modeling capabilities and associated adjustments (including advancing tip mach number, lateral directivity, static directivity and static duration adjustments); (10) metric computation process; and (11) development of a recursively-subdivided irregular grid methodology, which is used for computing noise contours (Chapter 4).

https://rosap.ntl.bts.gov/view/dot/12188/dot_12188_DS1.pdf

Integrated Noise Model (INM) Version 7.0 Technical Manual

Integrated Noise Model (INM) version 6.0 technical manual

The Federal Aviation Administration, Office of Environment and Energy, Noise Division (FAA, AEE-100) has developed Version 7.0 of the Integrated Noise Model (INM) with support from the ATAC Corporation and the Department of Transportation Volpe National Transportation Systems Center. The FAA Integrated Noise Model is widely used by the civilian aviation community for evaluating aircraft noise impacts in the vicinity of airports. The model is typically used in the U.S. for FAR Part 150 noise compatibility planning, FAR Part 161 approval of airport noise restrictions, and for environmental assessments and environmental impact statements under the current version of FAA Order 1050.1E. New features in INM 7.0 include: lateral attenuation calculations based on SAE-AIR-5662; flight path segmentation, flight procedure step types, bank angle calculations, and thrust reverser implementation based on ECAC Doc 29; helicopter modeling methods based on Version 2.2 of FAA’s Heliport Noise Model (HNM); an HNM study import function; a scenario annualization function allowing operations to be adjusted after performing a run; a multi-threaded run mode; fixed-spacing contour grid functionality; increased differentiation between different type of aircraft (civil, military, and helicopter); the ability to input location values in lat/long or X/Y; and many extended database fields. INM Version 7.0 software runs on PCs using a minimum hardware configuration of a Pentium III processor, Microsoft Windows 2000 or XP operating systems, 1.0-Gb RAM, mouse input device, hard disk drive, and CD-ROM drive.

https://rosap.ntl.bts.gov/view/dot/12187/dot_12187_DS1.pdf

Integrated Noise Model (INM) Version 7.0 User's Guide

This is the first of two volumes of a report on the Hybrid Propagation Model (HPM), an advanced prediction model for aviation noise propagation. This volume presents the noise level predictions for eleven different sets of propagation conditions, run by the HPM. The conditions include effects of uneven terrain, refractive atmosphere, and ground type transitions. The results are analyzed in detail and comparisons are made across four different source altitudes and between the different component models of the HPM. In addition, a scheme of “intelligent switching” between the HPM’s component models is posed as an approach to address the long runtimes of the HPM. The feasibility of this strategy is discussed and some points of caution regarding its implementation are identified. HPM results are compared to the Integrated Noise Model (INM) under uneven terrain conditions in Volume 2 of this report. The goal of this research is to enhance the modeling capabilities of the Aviation Environmental Design Tool (AEDT) and INM, particularly in complicated environments such as National Parks.

Paul J Gerbi

Papers

Integrated Noise Model (INM) Version 7.0 Technical Manual

Integrated Noise Model (INM) version 6.0 technical manual

Integrated Noise Model (INM) Version 7.0 User's Guide

Assessment of the Hybrid Propagation Model, Volume 1: Analysis of Noise Propagation Effects

Integrated Noise Model (INM), version 5.1 : technical manual