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Helicopter and Tiltrotor Noise Modeling Procedures Document

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Helicopter and Tiltrotor Noise Modeling Procedures Document ACRP Problem Statement: 89 Recommended Allocation: $250,000 Helicopter and Tiltrotor Noise Modeling Procedures Document Click here to see problem statement in IdeaHub: http://ideascale.com/t/UKsrZBVBS (Note: you must be a registered user in myACRP/IdeaHub.) TAGS: Airport Planning, Environment, Noise Impacts, Operations, Policy, Public Relations STAFF COMMENTS No comments. AVERAGE INDUSTRY RATING SUMMARY Committees1 Airport Community2 Achievable 3.00 3.50 Applicable 2.50 3.50 Implementable 2.00 3.50 Understandable 2.50 3.00 OVERALL 2.50 3.38 Notes: 1. Includes TRB aviation committees and committees from ACI-NA and AAAE. 2. Includes airport employees serving on active ACRP project panels. CLICK HERE TO SEE DETAILED INDUSTRY RATINGS CLICK HERE TO SEE DETAILED INDUSTRY COMMENTS ACRP OVERSIGHT COMMITTEE (AOC) DISPOSITION The average AOC rating among its voting members was 2.1 on a scale of 1 to 5. There was on discussion. The problem statement was not selected for ACRP funding and will be returned to the idea collection phase of ACRP’s IdeaHub. ACRP Problem Statement: 89 Helicopter and Tiltrotor Noise Modeling Procedures Document TAGS: Airport Planning, Environment, Noise Impacts, Operations, Policy, Public Relations OBJECTIVE The objective of this research effort is to develop written documentation on best available methods to model community noise generated from helicopter and tiltrotor operations. The document should address integrated and simulation modeling techniques, and methods for collecting and analyzing noise source data, and outline noise source development protocols. The language and format of the document shall be suitable for standards submission. BACKGROUND Existing noise modeling standards [SAE-AIR-1845; ICAO, Doc-29] for prediction of fixed wing community noise have been promulgated internationally and serve as the technical justification and defensible rationale upon which numerous noise models such as the Aviation Environmental Design Tool (AEDT) and the Integrated Noise Model (INM) rely. At present no such standards address modeling of helicopter or tiltrotor noise. The ACRP 02-44 Project provided seven key recommendations for improving AEDT (integrated) noise modeling which included metrical quantification, source acoustic emission fidelity, flight operations and flight mode capability and propagation/environmental modeling requirements. However, final recommendations could not be provided for maneuvering flight acoustic considerations, though research has certainly advanced significantly in recent years. Technical progress towards commercial operation of a new class of civil tiltrotors continues with expected entry into service of the AW609 tiltrotor expected in 2020. Presently AEDT does not have the capability to model tiltrotor operations, though existing models having tiltrotor modeling capability (AAM and formerly RNM) have been employed by the US DoD for some time. Recent cooperative helicopter flight tests conducted by NASA and FAA/Volpe have gathered significant data that is being used to seed various helicopter noise models such as AAM and AEDT, but maneuvering flight noise data was also gathered for validation of first principles and semi-empirical modeling tools such as CHARM-PSU-WopWop and FRAME. This supplemental information and the associated models have advanced and could provide critical insight for development of recommendations for modeling maneuvering flight acoustics. APPROACH TO RESEARCH Draw on the existing modeling tools and knowledge base to develop documentation for prediction of helicopter and tiltrotor community noise. This project should address both simulation and integrated noise modeling methods and leverage the series of recommendations for improvements in integrated noise modeling provided in ACRP 02-44. Recommended tasks include: • Literature review of helicopter and tiltrotor noise modeling, • Evaluation of new research related to maneuvering flight modeling, • Develop modeling recommendations for maneuvering flight modeling, and • Prepare a document on helicopter and tiltrotor noise modeling procedures that could serve as a start to a standards review process. COST AND JUSTIFICATION $250k. Cost includes modeling analysis; examination of new research for maneuvering flight modeling; outreach for peer review of new components not already documented in ACRP 02-44; and Preparation of Tiltrotor and Helicopter Noise Modeling Procedures technical documentation. RELATED RESEARCH Airport Cooperative Research Project (ACRP) No. 02-44, Sept. Available from http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=3439. Brentner, Kenneth S., et al., “Final Report, Rotorcraft Noise Abatement Operating Conditions Modeling,” ASCENT Project 6: https://s3.wp.wsu.edu/uploads/sites/192/2017/03/ASCENT-Project-6-Final-Report-v3.pdf Brentner, Kenneth S., et al., “ASCENT Project 38, Rotorcraft Noise Abatement Procedures Development,” https://ascent.aero/project/rotorcraft-noise-abatement-procedures-development/ European Civil Aviation Conference (ECAC), “Report on Standard Method of Computing Noise Contours around Civil Airports,” Doc 29 - 4th Edition, 7 December 2016 Greenwood, Eric, Benjamin May, Christopher Hobbs and Robert Rau, “A Maneuvering Flight Noise Model for Helicopter Mission Planning”, AHS Forum 2015. Greenwood, Eric “Fundamental Rotorcraft Acoustic Modeling from Experiments (FRAME)”, PhD Thesis, UMD, 2011. Leonardo Press Release, Rome, 27 February 2018, “Era Group to mark entry of AW609 tiltrotor into the US commercial market.” http://www.leonardocompany.com/en/-/hai-heliexpo-aw609-era Nelms, Douglas, “US Government Conducts Flight Testing to Prove Noise Prediction Models,” Vertiflite, Jan/Feb 2018. https://vtol.org/files/dmfile/Noise-Nelms_VF-JF181.pdf Page, Juliet A., Christopher M. Hobbs, Benjamin May, Eric Boeker, Harry Brouwer, Clint Morrow, 2015. “Guidance for Helicopter Community Noise Prediction Final Report”, National Academies of Science, Transportation Research Board, Saetti, Umberto., “Rotorcraft Simulations with Coupled Flight Dynamics, Free Wake, and Acoustics”, 2016, 10.13140/RG.2.1.2259.3529. Society of Automotive Engineers (SAE), 1986. “Procedure for the Calculation of Airplane Noise in the Vicinity of Airports”, SAE Standards AIR 1845, issued Mar. Transportation Research Board (TRB) 2016. “Recommended Community Noise Model Enhancements to Improve Prediction of Helicopter Activity Impacts”, National Academies of Science, Transportation Research Board, Airport Cooperative Research Project, Research Results Digest 24, January. Available from: http://www.trb.org/main/blurbs/173719.aspx. Watts, Michael, Eric Greenwood, “Maneuver Acoustic Flight Test of the Bell 430 Helicopter - Data Report,” NASA TM 2014-218266, 2014. IDEA CREATOR Person who first shared the idea with the IdeaHub community. Juliet Page Technical / Professional (non-supervisory) U.S. DOT, Volpe Center OWNER/SUBMITTER Person who volunteered to be responsible for developing the idea into a problem statement. Juliet Page Technical / Professional (non-supervisory) U.S. DOT, Volpe Center .
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