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International Civil Aviation Organization Colloquium on Environmental Aspects of Aviation Aircraft Emissions - The Way Forward Willard Dodds, Chairman ICCAIA Noise and Emissions Committee Montreal, 9-11 April 2001. Elements of ICAO CAEP Approach. Terms of Reference
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International Civil Aviation OrganizationColloquium on Environmental Aspects of AviationAircraft Emissions - The Way ForwardWillard Dodds, ChairmanICCAIA Noise and Emissions Committee Montreal, 9-11 April 2001
Elements of ICAO CAEP Approach • Terms of Reference • Technical Feasibility - Safety • Environmental Benefit • Economic Reasonableness • Environmental Balance/Tradeoffs • Noise • Climate Change • Local Air Quality • Program Balance • Source Reductions (Technology) • Operational Measures (Airlines and ATC) • Market Based Measures Unique ICAO Resources Address Complex Issues
Emission Issues Issue Key Species Mitigation • Climate Change - Carbon Dioxide (CO2) - Fuel Efficiency - Water Vapor - Operational Measures - NOx - Combustor Design • Local Air Quality - NOx - Combustor Design - Carbon Monoxide (CO) - Operational - Unburned Hydrocarbon (HC) Measures - Smoke/Soot
Local Air Quality • Continuous emissions reductions • ICAO Data Bank provides current emissions certification data • Required design/test margins ensure that certificated product emissions are below ICAO limits Ref: The Boeing Company
Climate Change • Continuous fuel efficiency improvements driven by market forces • Market based measures are being considered by ICAO • Long term - open emissions trading • Near term - voluntary programs 70% Fuel Efficiency Improvement over 40 Years
CO2/NOx Trade • Higher engine pressure ratio and bypass ratio reduce CO2/improve fuel efficiency (SFC) and facilitate noise reduction SFC SFC (lb/lb-hr, or EI NOx) 0 10 20 30 40 50 60 Overall Pressure Ratio
CO2/NOx Trade • Higher engine pressure ratio and bypass ratio reduce CO2/improve fuel efficiency (SFC) and facilitate noise reduction • Higher pressure ratio requires higher flame temperature, increasing NOx formation rate NO SFC X SFC (lb/lb-hr, or EI NOx) 0 10 20 30 40 50 60 Overall Pressure Ratio
CO2/NOx Trade • Higher engine pressure ratio and bypass ratio reduce CO2/improve fuel efficiency (SFC) and facilitate noise reduction • Higher pressure ratio requires higher flame temperature, increasing NOx formation rate • Better NOx technology needed to avoid increased emissions NO SFC X SFC (lb/lb-hr, or EI NOx) 0 10 20 30 40 50 60 Overall Pressure Ratio
Emissions Technology Outlook • Continuous technology improvement has substantially reduced all emissions from modern engines • Government and industry emissions reduction technology programs are underway • Barriers to wider introduction of these technologies: • high development and certification investment with low production volume • durability, operability, reliability & production cost risks • environmental tradeoffs • unclear policy objectives • unrealistic short term technology expectations • ICAO WG 3 Long Term Goals Group is addressing technology transition issues
Emissions Technology Expectations • 17 ICCAIA - Working Group 3 Papers prepared for CAEP/5 • Papers support IPCC Special Report projection of 20% improvement in fuel efficiency between 1997 and 2015 • NOx reduction technology is progressing faster than the IPCC scenario for NOx emissions 30-50% below CAEP/2 limits by 2020 • Concerns relative to the rate of future progress due to • uncertain research funding • environmental and technological tradeoffs/priorities • increasing challenge to improve on current technology
Summary and Conclusions • ICAO is uniquely qualified to set aviation environmental standards • Brings together resources to balance complex trade-offs • Avoids proliferation of confusing, inconsistent and counterproductive local rules • Globally harmonized approach for a global industry • Manufacturers continually work to improve emissions technologies • Need consistent and consolidated scientific basis for valid trade-off analyses • Aircraft emissions reduction efforts should be part of a balanced program including improved operational factors • Successful long term research requires continuous support and consistent goals • CAEP/6 Work Program has proper elements to move forward on local air quality and climate