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From page 3... ... 3  Do the current databases, input variables, algorithms and sub-models of AEDT provide a reasonable estimate of taxi-related emissions? To answer these questions, the literature review focused on the following four categories of information: Information Categories  Aircraft Performance Characteristics – including aircraft taxi/idle times-in-modes under alternative airfield conditions, single-engine taxi procedures, flight data recorder (FDR) Read the entire page →
From page 4... ... 4  Task 6: Develop List of Potential AEDT Improvements  Task 7: Stakeholder Outreach  Task 8: Interim Report  Task 9: Identification of Near-Term Model Improvements  Task 10: Steps Needed for Implementation  Task 11: Final Report Notably, for the interrelated Tasks 4, 5 and 6 designed to develop the initial list of potential model improvements, the Research Team targeted three fundamental elements (i.e., factors) within the current AEDT framework that the model uses to calculate aircraft engine emissions during the taxi/idle mode. Read the entire page →
From page 5... ... 5 1980s, were derived from the U.S. Environmental Protection Agency's (EPA's) Read the entire page →
From page 6... ... 6 Table 2 AEDT Taxi/Idle Emission Improvement Research Approach Taxi/Idle Emissions Computational Factors Research Parameter(s) Research Accomplishments Improvement Option(s) Read the entire page →
From page 7... ... 7 considerations included in modeling. which reduced taxi procedures are in use or provide data to indicate the percentage of time or frequency when aircraft are taxied with fewer than all engines. Read the entire page →
From page 8... ... 8 Table 3 ASPM Aircraft Taxi Times Airport Size No. of Runways No. Read the entire page →
From page 9... ... 9 4 7 6 13 -27 5 1 5 13 -31 Hub – Small Airportd 2-5 10 5 12 -35 2 5 4 12 -38 3 3 5 12 -35 4 1 4 9 -50 5 1 5 13 -31 All Non-hub 2 3 5 12 -35 a When compared to the current default taxi in/out values of seven and 19 minutes, respectively. b Large airport = Airports that account for at least one percent of the total U.S. Read the entire page →
From page 10... ... 10 DAY James M Cox Dayton Intl. Small 3 5 13 -31 DCA Ronald Reagan Washington National Large 3 5 16 -19 DEN Denver Intl. Read the entire page →
From page 11... ... 11 PBI Palm Beach Intl. Medium 3 4 13 -35 PDX Portland Intl. Read the entire page →
From page 12... ... 12 Listed in Table 5, these FDR groundspeed data were evaluated for seven high-bypass turbofan jet aircraft engines from four engine families, which included the following:  Rolls-Royce Trent series,  Rolls-Royce RB211 series,  PW4000 by Pratt & Whitney, and the  CFM56 by CFM International. As shown in Table 5, the FDR data for these "Test Data Engines" (representing approximately 68,000 taxi in and 111,000 taxi out events) Read the entire page →
From page 13... ... 13 number and length of the taxiways and whether they are assigned for arrivals, departures, or both. 3.2 Fuel Flow Rates (FFRs) Read the entire page →
From page 14... ... 14 Table 6 Fuel Flow Rates (FFRs) Method Study Engine (Airframe When Provided) Read the entire page →
From page 15... ... 15 Read from Cockpit CFM56-3B1 84 CFM56-3B2 87 APEX3 CFM56-3B1 73 (aircraft 1) , 88 (aircraft 2) Read the entire page →
From page 16... ... 16 The Research Team reviewed studies that address the dependence of CO, HC, and NOx EIs on FFR and ambient temperature. Among others, this dependence has been studied as part of the following projects: APEX (1) Read the entire page →
From page 17... ... 17 same as that observed for the CFM56-7B family of engines. For engines that idle at intermediate FFRs (e.g., 88 percent of the ICAO FFR instead of 85 percent or 90 percent) Read the entire page →
From page 18... ... 18 For example, consider a CFM56-7B22 operating at 0.095 kg/s. Read the entire page →
From page 19... ... 19 3.4.2 Alternative Taxi Systems Recognizing that the reduced use of an aircraft's engines on the ground could result in significant fuel savings, at least two manufacturers/joint ventures are developing methods to taxi aircraft on the ground with no engines operating. Honeywell, and the aerospace firm Safran, have been working together to develop an electric motor that would power an aircraft's main wheels, the motor being powered by an aircraft's auxiliary power unit (APU) Read the entire page →

From page 3...

... 3  Do the current databases, input variables, algorithms and sub-models of AEDT provide a reasonable estimate of taxi-related emissions? To answer these questions, the literature review focused on the following four categories of information: Information Categories  Aircraft Performance Characteristics – including aircraft taxi/idle times-in-modes under alternative airfield conditions, single-engine taxi procedures, flight data recorder (FDR)