Integrated Noise Model (INM)
INM Version 7.0 is a significant improvement over the 6x series. In addition to several updates related to aircraft noise/performance for commercial aircraft, Version 7.0 includes detailed modeling of helicopter noise based on the Federal Aviation Administration’s (FAA) Heliport Noise Model (HNM) Version 2.2, and algorithms consistent with updated guidance documents, including the European Civil Aviation Conference (ECAC) Doc 29 (3rd Edition) “Report on Standard Method of Computing Noise Contours around Civil Airports”.
- INM 7.0 Order Form (PDF)
New Features
INM Version 7.0 includes the following new operational and computational features:
- Improved helicopter noise modeling capabilities
- Based on HNM Version 2.2
- Improved helicopter-specific NPD and directivity implementation
- Expanded helicopter operational modeling functionality
- Compliance with ECAC Doc 29
- New SAE-AIR-5662 Lateral Attenuation algorithms
- Updated Thrust Reverser implementation
- Bank angle implementation
- Updated flight path segmentation
- Additional procedural profile step types
These improvements to the noise and flight performance modeling algorithms in INM Version 7.0 may produce minor changes in output results when compared to previous versions of INM. The magnitude of these changes is study dependent.
INM Version 7.0 also includes the following new software features:
- Scenario-Case Format
- Allows for further categorization of input data within an INM study.
- Allows for annualization where a user may adjust noise contributions of individual cases in a scenario by a scale factor and an annualization percentage without re-running that scenario.
- New Multi-threaded run mode
- Utilizes multi-core and hyper-threaded machines
- Graphical User Interface Changes
- New menu options
- Updated windows to incorporate new functionality
Many of the aforementioned updates to INM are in preparation for its integration into FAA’s Aviation Environmental Design Tool (AEDT). AEDT is a comprehensive suite of software tools that will allow for thorough assessment of the environmental effects of aviation. The main goal of the effort is to develop a new capability to assess the interdependencies between aviation-related noise and emissions effects, and to provide comprehensive impact and benefit-cost analyses of aviation environmental policy options.
Database Updates and Changes
Although no new aircraft were added to INM Version 7.0, the noise/performance database was updated to include the new helicopter data that previously resided in the HeloExample study distributed with the INM. Because of the new helicopter modeling functionality in INM Version 7.0, helicopters in INM are represented by sets of NPDs for a variety of approach, departure and level flight operational modes, which utilize helicopter in-flight directivity. INM also includes separate NPDs and directivity adjustments for a variety of static operational modes. The helicopter data updated in INM Version 7.0 are:
- Augusta A-109 (A109)
- Bell 206L Long Ranger (B206L)
- Bell 212 Huey (B212)
- Bell 222 (B222)
- Boelkow BO-105 (BO105)
- Boeing Vertol 234 (CH47D)
- Eurocopter EC-130 w/Arriel 2B1 (EC130)
- Hughes 500D (H500D)
- McDonnell Douglas MD-600N w/ RR 250-C47M (MD600N) – level flight only
- Robinson R22B w/Lycoming 0320 (R22)
- Sikorsky S-61 (S61)
- Sikorsky S-65 (S65)
- Sikorsky S-70 Blackhawk (S70)
- Sikorsky S-76 Spirit (S76)
- Aerospatiale SA-330J Puma (SA330J)
- Aerospatiale SA-341G/342 Gazalle (SA341G)
- Aerospatiale SA-350D Astar (SA350D)
- Aerospatiale SA-355F Twin Star (SA355F)
- Aerospatiale SA-365N Dauphin (SA365N)
Several fixed-point approach profiles were also modified, in order to bring them into conformance with the INM method of modeling touchdown and reverse thrust.
Previous Versions of INM
INM 7.0, released on April 30, 2007, is the first full INM release since INM 6.2a (October 2006), and it is the first in a new series of releases since INM 6.0 (September 1999). INM 7.0 is distributed on a CD-ROM accompanied with a user's guide, and it is supported to run in Windows 98/NT 4.0/2000/XP operating systems. The INM 7.0 technical manual is forthcoming and will be distributed to all registered users as soon as it is available. A study was recently completed for comparing noise contours between INM versions 7.0 and 6.2a (PDF). As with previous versions of INM, updates to the 7.x series will be made available for download to registered users.
The following previous versions of INM are available upon request from the Office of Environment & Energy:
Release Notes of Previous Versions of INM
- 6.2a (November 30, 2006)
- 6.2 (May 22, 2006)
- 6.1 (March 4, 2003)
- 6.0c (September 21, 2001)
- 6.0b (January 16, 2001)
- 6.0a (May 19, 2000)
- 6.0 (September 30, 1999)
Helicopter Modeling
Prior to the release of INM Version 7.0, helicopter noise impacts in the vicinity of terminal operations were modeled with the HNM. Current helicopter noise assessments should be conducted with INM Version 7.0. However, the following previous version of HNM and associated documentation are available upon request from the Office of Environment & Energy.
