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From page 70... ... Commercial Space Vehicle Emissions Modeling 59 6 AEDT Integration Plan The projected growth of the commercial space industry will increase the demand for a standard emissions model to assess the environmental impacts of commercial space transportation. AEDT is the standard tool used to model emissions and noise from commercial aviation in the United States. Read the entire page →
From page 71... ... Commercial Space Vehicle Emissions Modeling 60 Elements unique to space vehicles:  Space vehicles may be propelled by a combination of different types of engines that use different propellants. AEDT integration considerations:  Add a new table for spacecraft to the existing AEDT fleet database. Read the entire page →
From page 72... ... Commercial Space Vehicle Emissions Modeling 61 vehicle performance. Thus, space vehicles do not fly standard segments as defined in AEDT. Read the entire page →
From page 73... ... Commercial Space Vehicle Emissions Modeling 62 The environmental impacts of space vehicle emissions vary depending on the atmospheric layer where they are emitted. For this reason, FAA guidelines state that environmental documents for commercial space vehicle operations should report emissions inventories by atmospheric layer [121, 122] Read the entire page →
From page 74... ... Commercial Space Vehicle Emissions Modeling 63 Elements unique to space vehicles:  Space vehicles traverse the entire vertical extent of the atmosphere.  Taxi and ground roll mode categories are not applicable to space vehicles that launch or land vertically. Read the entire page →
From page 75... ... Commercial Space Vehicle Emissions Modeling 64 Step 3: Add Launch Pads and Landing Zones The existing runway definitions in AEDT can be used for space vehicles that launch and land horizontally at airports and spaceports. However, the AEDT user interface should be modified to enable users to add launch pads and landing zones for space vehicles that launch and land vertically. Read the entire page →
From page 76... ... Commercial Space Vehicle Emissions Modeling 65 Figure 34. Conceptual design of the spacecraft trajectory dialog. Read the entire page →
From page 77... ... Commercial Space Vehicle Emissions Modeling 66 Figure 35. Conceptual design of the static operation wizard. Read the entire page →
From page 78... ... Commercial Space Vehicle Emissions Modeling 67 The pseudocode is organized into two functions:  CalculateVehicleEmissions calculates the mass of propellant burned and the mass of each pollutant emitted by the space vehicle during each trajectory segment. This function sums the propellant burned and pollutants emitted by all engines on the vehicle. Read the entire page →
From page 79... ... Commercial Space Vehicle Emissions Modeling 68 The pseudocode for the commercial space vehicle emissions model is listed in Code Block 1 and Code Block 2. The syntax is similar to Python in terms of function definitions, comments, and indexing. Read the entire page →
From page 80... ... Commercial Space Vehicle Emissions Modeling 69 define CalculateEngineEmissions(time, altitude, massFlowRate, burnTime, primaryEI) # Constants feet2km = 0.3048/1000 # Molecular weight MW[CO] Read the entire page →
From page 81... ... Commercial Space Vehicle Emissions Modeling 70 6.4 Spreadsheet Emissions Estimator Tool The algorithms provided in the previous section were implemented in a spreadsheet emissions estimator tool to provide future programmers with an implementation example of the commercial space vehicle emissions model. The tool includes multiple worksheets to demonstrate:  User inputs for vehicle and operational data,  Emissions model calculations, and  Propellant burn report and emissions inventory outputs. Read the entire page →
From page 82... ... Commercial Space Vehicle Emissions Modeling 71 Figure 36. User input worksheet for vehicle parameters. Read the entire page →
From page 83... ... Commercial Space Vehicle Emissions Modeling 72 Figure 37. User input worksheet for operational data. Read the entire page →
From page 84... ... Commercial Space Vehicle Emissions Modeling 73 Emissions Inventory and Propellant Burn Report Figure 38 shows a screenshot of the output emissions inventory and propellant burn report grouped by operations mode. The report includes the mass of propellant burned and the mass of each pollutant emitted by the three main engines and the two solid boosters during each operational mode. Read the entire page →
From page 85... ... Commercial Space Vehicle Emissions Modeling 74 Figure 38. Emissions inventory and propellant burn report grouped by operations mode. Read the entire page →
From page 86... ... Commercial Space Vehicle Emissions Modeling 75 6.5 Software Verification and Validation The spreadsheet emissions estimator tool described in the previous section is intended to provide an implementation example of the commercial space vehicle emissions model that future programmers can refer to during AEDT integration. However, integrating the commercial space vehicle emissions model with AEDT is a multi-step process that includes being added to the AEDT development roadmap, implementing the emissions model in AEDT, and releasing a new version of AEDT. Read the entire page →

From page 70...

... Commercial Space Vehicle Emissions Modeling 59 6 AEDT Integration Plan The projected growth of the commercial space industry will increase the demand for a standard emissions model to assess the environmental impacts of commercial space transportation. AEDT is the standard tool used to model emissions and noise from commercial aviation in the United States.