MOTIVATIONTHE DESIGN AND OPERATION OF AIR TRANSPORTATION SYSTEMS REQUIRES THE CONSIDERATION OF MULTIPLE OPERATING CHARACTERISTICS SUCH AS ENVIRONMENT SAFETY CAPACITY ECONOMIC PERFORMANCE. THESE CHARACTERISTICS CAN BE USED TO DEFINE DIMENSIONS OF A TRADE SPACE FROM WHICH TRADE-OFFS BETWEEN THEM CAN BE EXPLORED IN SUPPORT OF OPERATIONAL SYSTEM IMPROVEMENT AND POLICY DECISIONS. THE TRADE SPACEWHICH MUST BE CONSIDERED HAS EVOLVED AND BECOME SIGNIFICANTLY MORE COMPLEX AS THE AIR TRANSPORTATION SYSTEM HAS MATURED AND AS THE SOCIETAL EXPECTATIONS FOR THE SYSTEM HAVE INCREASED. INITIALLY THERE WAS OFTEN A SINGLE DOMINANT OBJECTIVE TO SYSTEM ENHANCEMENTS SUCH AS IMPROVING SAFETY. AS THE SYSTEM BECAME MORE CONGESTED NEW DRIVERS SUCH AS CAPACITY AND EFFICIENCY EMERGED. MORE RECENTLY ENVIRONMENTAL CONSIDERATIONS ARE INCREASING AND MUST BE BALANCED AGAINST THE OTHER TRADITIONAL METRICS IN OPTIMIZING HOW THE SYSTEM OPERATES AS WELL AS DEFINING THE REQUIREMENTS FOR SYSTEM EVOLUTION AND ENHANCEMENT SUCH AS NEXTGEN.IN ADDITION TO THE "MACRO-LEVEL" TRADE-OFFS BETWEEN SYSTEM PERFORMANCE CATEGORIES SUCH AS ENVIRONMENT SAFETY CAPACITY AND ECONOMICS THERE ARE ALSO TRADE-OFFS OCCURRING WITHIN A GIVEN SYSTEM PERFORMANCE DIMENSION SUCH AS BETWEEN THE DIFFERENT ENVIRONMENTAL IMPACT AREAS OF NOISE AIR QUALITY AND CLIMATE. THIS RESULTS IN A HIGHLY DIMENSIONAL "TRADE HYPERSPACE" WHICH NEEDS TO BE CONSIDERED TO BETTER OPTIMIZE THE SYSTEM PERFORMANCE. THE TRADITIONAL TRADE ANALYSIS TECHNIQUES WHICH HAVE BEEN EMPLOYED IN AIRTRANSPORTATION SYSTEM DEVELOPMENT SUCH AS SIMPLE COST-BENEFIT ANALYSES DO NOT SIMULTANEOUSLY CONSIDER THESE MULTIPLE DIMENSIONS.THE DIFFERENT VALUE STRUCTURES DIFFERENT STAKEHOLDERS PLACE ON ATTRIBUTES OF SYSTEM PERFORMANCE MAKE IT EVEN MORE DIFFICULT TO HAVE A GLOBAL DEFINITION OF OPTIMALITY ON WHICH TO BASE TRADE ANALYSES.OBJECTIVESTHE OBJECTIVES OF THIS RESEARCH ARE TO DEVELOP METHODOLOGIES FOR MULTI-DIMENSIONAL TRADE ANALYSIS AND OPTIMIZATION OF AIR TRANSPORTATION SYSTEM PERFORMANCE INCLUDING ENVIRONMENTAL CONSIDERATIONS. IN ADDITION NEW APPROACHES FOR DEFINING UTILITY WILL BE EXPLORED TO ADDRESS ISSUES OF NON-HOMOGENOUS METRICS OF PERFORMANCE AND DYNAMIC STAKEHOLDER DEPENDANT VALUE STRUCTURES WHICH ARISE IN CONSIDERING THE BALANCE BETWEEN ENVIRONMENTAL AND OTHER SYSTEM PERFORMANCE. THE SPECIFIC OBJECTIVES OF THIS RESEARCH ARE TO:1. DEVELOP A FRAMEWORK FOR "HYPERSPATIAL" TRADE ANALYSES APPROPRIATE FOR EVALUATING MULTI-ATTRIBUTE TRADES IN AIR TRANSPORTATION SYSTEMS.2. DEVELOP APPROACHES TO DEFINING UTILITY WHICH INCLUDE ENVIRONMENTAL AND OTHER SYSTEM PERFORMANCE PARAMETERS AND WHICH CAN FORMALLY INCORPORATE DIFFERENT VALUE STRUCTURES FROM MULTIPLE STAKEHOLDERS IN THE AIR TRANSPORTATION SYSTEM.3. EXPAND CURRENT AIR TRANSPORTATION SYSTEM MODELS TO INCORPORATE THESE ADVANCED UTILITY AND MULTI-DIMENSIONAL ANALYSIS METHODS.4. EVALUATE THE METHODS BY APPLYING THEM TO ONE OR MORE SAMPLE TRADE PROBLEMS WHICH INCLUDE ENVIRONMENTAL ISSUES WITHIN THE CURRENT AIR TRANSPORTATION SYSTEM AND HENCE REFINE THE METHODOLOGIES.5. FURTHER EVALUATE THE METHODS BY EXPLORING MORE SIGNIFICANT TRADE PROBLEMS INCLUDING THE INCORPORATION OF NEW OPERATIONAL CAPABILITIES AND CONCEPTS INCLUDING REPRESENTATIVE ELEMENTS OF NEXTGEN.EXPECTED SIGNIFICANCETHE EXPECTED SIGNIFICANCE OF THIS RESEARCH WOULD BE PROFOUND. AT PRESENT MANY OPERATIONAL INVESTMENT AND POLICY DECISIONS ARE BASED ON VERY SIMPLE ONE OR TWO DIMENSIONAL TRADE ANALYSIS AND DO NOT FULLY INCORPORATE IMPORTANT CONSIDERATIONS SUCH AS THE SPECTRUM OFENVIRONMENTAL IMPACTS. THE METHODS DEVELOPED IN THE PROPOSED RESEARCH ARE EXPECTED TO ENABLE SIMULTANEOUS CONSIDERATION OF MULTIPLE OBJECTIVES WHICH WILL BE CRITICAL AS ENVIRONMENTAL CONSIDERATIONS BECOME COMPARABLE IN IMPORTANCE TO SAFETY CAPACITY AND ECONOMICS IN NEXTGEN DEVELOPMENT.