The Evolution of Modeling Aviation’s Environmental Impact

1. Federal Aviation Administration Presented at the AIAA/AAAF Aircraft Noise and Emissions Reduction Symposium By Dr. Lourdes Q. Maurice Chief Scientific and Technical Advisor for Environment Office of Environment & Energy, FAA May 25, 2005 The Evolution of Modeling Aviation’s Environmental Impact

2. Growth in Computing Power (From Hans Moravec: "When will computer hardware match the human brain?" (1998, Jour. of Transhumanism, Vol.1); courtesy of the World Transhumanist Association)

3. Outline • Where We Have Been • Where We Are Today • Where We Are Going: • Interrelationships • Long-term challenges • Concluding Observations

4. Aviation Environmental Issues Global climate The potential impact of aviation on global climate Community Noise Impacts Dealing with significant aircraft noise impacts around airports Water Quality Limiting or reducing impact of aviation on water quality Air Quality Limiting or reducing impact of aviation on local air quality

5. Future Aviation Environmental Goals Work with local governments and airspace users to provide capacity in the United States airspace system that meets projected demand in an environmentally sound manner http://www1.faa.gov/aboutfaa/flightplan.cfm Environmental Protection that Allows Sustained Aviation Growth -- community noise and local air quality emissions from aviation that significantly impact human health and welfare reduced in absolute terms Next Generation Air Transportation System Integrated Plan http:/jpdo/aero

6. Where We Have Been: Local Applications Individual Airport Noise Contours & Emissions Inventories/ Concentrations INM 3000 ft 1978 2005

7. Where We Are Today: Airspace Applications Assess impacts of airspace redesign and benefits of mitigation options 18000 ft INM 3000 ft 1999 2005

8. Where We Are Today: Global Applications Global Noise Exposure & Emissions Inventories 18000 ft INM 3000 ft 1998 2005

9. Where We Are Going: Interrelationships • Interdependency Dominates • Assessing Multiple Environmental Impacts • Monetizing Impacts

10. Where We Are Going: Analyses Drivers • A new noise stringency standard • A new NOx stringency LTO standard • A new NOx cruise standard • A new particulate matter standard • Potential Phaseouts • Use of market-based options, operational procedures, and land-use measures as alternatives or complimentary elements of any noise and emissions standards

11. Where We Are Going: Multidisciplinary Approach • Great progress reducing environmental impact of aviation • Despite interrelationships – noise and emissions addressed separately • Delivering continuing reductions in noise and emissions necessitates an interdisciplinary approach • Economic considerations vital to a robust analyses • Design advances and increasing computing power offer tremendous possibilities for new analyses tools & approaches

12. Noise Other Emissions Fuel Burn/CO2 Where We Are Going: Environmental Interrelationships • Continuous Descent Approach • Reduced Noise • ReducedFuel Burn/CO2 • Improved aerodynamic efficiency and reduced weight • - ReducedCO2 • Reduced Noise • Reduced NOx • Nacelle Modifications • Reduced Noise • IncreasedFuel Burn/CO2 • Increased engine bypass ratio • ReducedFuel Burn / CO2 • ReducedNoise • IncreasedNOx • Increased Engine Pressure Ratio & Temperatures • ReducedFuel Burn / CO2 • Reduced HCandCO • - IncreasedNOx

13. Where We Are Going: Definitions of New Tool Sets • Environmental Design Space (EDS)An aircraft systems model that integrates engine and aircraft design with aircraft operations to examine environmental performance and technology development providing a single source of aircraft data to AEDT. • Aviation Environmental Design Tool (AEDT) Merging of existing tools and new modules into both a publicly available, regulatory/planning component (Local) and the policy component of AEDT (Global). • Aviation Environmental Portfolio Management Tool (APMT)The economic analysis capability to be integrated with AEDT and EDS.

14. Where We Are Going: New Tool Set Conceptual Overview

15. Where We Are Going: Environmental Design Space • Future aircraft • Performance? • Cost? • Environmental Impact? • How will designs be shaped by • New technology • Demand • Policies • Policies and market scenarios • Cast as objectives and constraints for • Multi-disciplinary design and optimization problem 1kg NOx = 7,500 lbs GTOW 1dB (cum) = 5,500 lbs GTOW

16. Economic Analyses (macro) Where We Are Going: Monetizing Impacts • Costs • Benefits monetizing process Should try to monetize everything WHO has guidelines on health effects of noise & EPA on health effects of emissions ‘The Balance Sheet' (micro) THE ANSWER Measure of ‘overall goodness’ of various measures

17. Where We Are Going: Long-term Challenges • Incorporating new noise metrics & addressing new environments, e.g., • Sonic boom • Low noise environments

18. Where We Are Going: Long-term Challenges • Incorporating new noise metrics & addressing new environments • Accounting for Chemical Reactions to address particulates and hazardous air pollutants • Assessing the whole Transportation System

19. Average composition Parafins 60% Naphthenes 20% Aromatics 20% Sulfur 500 ppm Jet Fuel Chemical Composition

20. Fuel System Combustor F ~0.5-1.5) (1755 K, 35 bar, (436 K, 70 bar) PAH Fast Soot Condensation reactions Parent aromatic hydrocarbon CH x Slow Fragmentation Soot C H reactions 2 x C H Aliphatics 3 x Soot Formation Mechanisms

21. Recommended Complexity of Fuel Models

22. Where We Are Going: Long-term Challenges • Incorporating new noise metrics & addressing new environments • Accounting for Chemical Reactions to address particulates and hazardous air pollutants • Assessing the whole Transportation System

23. Summary • Environment could be a key constraint on aviation’s capacity to grow • We must continue to reduce environmental impact of aviation - a multidisciplinary analyses & optimization approach is key • We must lay the foundation to deal with long-term challenges • We need to consider the policy implications of new models so that public policy does not seriously lag our capabilities