Configuration

The Configuration window is used to define the aircraft's fuel and payload configuration and consists of four tabs

• Basic
• Stations
• Fuel
• Inertia

If you are calculating it dynamically within the currently selected Acceleration performance model, this information is necessary for the accurate determination of angle of attack The angle between the body X axis and the projection of the velocity vector onto the body XZ plane. The velocity vector is the velocity of the object as observed in the object's central body fixed coordinate system..

You can access the Configuration window by two methods - which produce different outcomes. If you open this window by clicking Default Configuration in the Aircraft Properties window, the changes made are saved to the catalog copy of the aircraft. The changes are not updated for the current mission or any other mission using the same aircraft model.

If you open this window by clicking the Configuration button in the Mission window, the changes made are saved to the current mission only. To alert you of this, the Configuration button displays an exclamation mark. .

Typically the configuration of an aircraft is mission-dependent. When an aircraft is selected for a mission, the default configuration is loaded once and embedded into the mission.

Any changes made to the aircraft's default configuration is not updated to missions where the aircraft is already selected. To utilize the new default configuration, you must select another aircraft and then re-select the updated aircraft. This paradigm protects the integrity of the configurations you have defined in other missions.

Basic

The Basic tab is used to define the empty parameters of the aircraft, and displays the total values, based on the stations and fuel tanks defined for it. Click Copy Configuration to save all of the configuration settings in this window to the clipboard; click Paste Configuration to define all of the configuration settings in this window with values saved on the clipboard. Click Check Performance Model Weight Limits to verify that your configuration is valid with respect to the performance models that have been defined for the aircraft.

Table - Basic Properties

Parameter	Description
Empty Weight	The weight of the aircraft without any fuel.
Total Weight	Indicates the total initial state weight of the aircraft including the fuel and payload weights.
Max Landing Weight	Indicates the maximum weight that the aircraft can bear when landing.
Total Weight - Full Fuel Tanks	Indicates the total weight of the aircraft including the fuel and payload weights, when the fuel tanks are full.
Base Drag Index	The drag index of the aircraft without any fuel or payload.
Total Drag Index	Indicates the total drag index of the aircraft including the fuel and payload drag index contributions. When calculating the aerodynamics of the aircraft, this value is multiplied by 1e-4 and added to Cd-0.
Characteristic Length	The reference length of the aircraft that is used to calculate Reynolds number. Reynolds number is the ratio of inertial resistance to viscous resistance for a flowing fluid. Conventional aircraft fly at a relatively constant Reynolds number, whereas hypersonic vehicles operate over a large range of Reynolds numbers ranging from turbulent flow at low altitudes to laminar flow at high altitudes.
Empty CG	The center of gravity of the aircraft at its empty weight; enter the Cartesian values that describe the center of gravity for the specific aircraft you are modeling, or leave these values set to zero if you don't have these specifications available to you. This value as used in Aviator is an arbitrary point and does not correspond to a specific point in the aircraft, and therefore does not affect the flight path or attitude of the aircraft; it is simply used to define the relative positions of internal fuel tanks and stations.
Total CG	Indicates the initial state center of gravity, taking into account stations and internal fuel tanks.

Stations

The Stations tab is used to define internal fuel tanks, stations, and external fuel tanks that are attached to the stations. A list of currently defined stations, with the aircraft itself at the top, is displayed on the left. You can use a right-click menu within the list to Add..., Delete, or Rename stations.

There are two buttons beneath the list. Click Add... to add an object to the currently selected object in the list; a selection window with valid objects to add will appear. If the currently selected object cannot be a parent to another item, the Add... button will be grayed out. Click Delete to remove the currently selected object.

If you have edited a parameter for one of the objects, you can click Apply to save that change and continue working in the window.

Internal Fuel Tank

An internal fuel tank is a fuel tank that is contained within the aircraft.

Table - Internal Fuel Tank Properties

Parameter	Description
Tank Name	Enter a specific name for the fuel tank, if desired.
Capacity	The fuel capacity, in weight, of the fuel tank; this value cannot be less than the initial state.
Initial State	The amount of fuel contained in the tank at the beginning of the mission; this value cannot exceed the Capacity.
Consumption Order	The fuel tank's place in the order in which fuel is consumed. The aircraft will empty each tank before beginning to consume from the next.
Parent Relative Position	Enter the Cartesian values that describe the position of the fuel tank relative to the aircraft's empty center of gravity.

Station

A station is a mounting point for an external fuel tank.

Table - Station Properties

Parameter	Description
Station Name	Enter a specific name for the station, if desired.
Parent Relative Position	Enter the Cartesian values that describe the position of the station relative to its parent object, or to the aircraft's empty center of gravity if there is no parent object.

External Fuel Tank

An external fuel tank is a fuel tank that can be attached to a station.

Table - External Fuel Tank Properties

Parameter	Description
Tank Name	Enter a specific name for the fuel tank, if desired.
Empty Weight	The empty weight of the fuel tank.
Capacity	The fuel capacity, in weight, of the fuel tank; this value cannot be less than the initial state.
Initial State	The amount of fuel contained in the tank at the beginning of the mission; this value cannot exceed the Capacity.
Consumption Order	The fuel tank's place in the order in which fuel is consumed. The aircraft will empty each tank before beginning to consume from the next.
Drag index	The drag index of the fuel tank, which contributes to the Total Drag Index of the aircraft.

Fuel

The Fuel tab displays a list of all of the fuel tanks defined for the aircraft, in their consumption order. You can edit the Consumption Order, Capacity, and Initial State parameters of any of the fuel tanks by double-clicking in the field. The total fuel capacity and initial state of the aircraft are displayed below the list. You can click Add/Remove Tanks... to flip back to the Stations tab, where you can add and remove fuel tanks, and modify additional parameters that are not displayed on this tab.

Inertia

The Inertia tab enables you to evaluate aircraft maneuverability and control authority by defining an inertia matrix based on the aircraft's shape, dimensions, and mass. During flight, this intertia matrix will be compared to values defined in dynamics/moments performance models to calculate if control authority is significant for desired maneuvers. Aviator will not alter trajectory based on inertia and dynamics limits, but is used to compute flight profile Control Force Required. The combination of vehicle weight and its dimensions provide the standard formulaic values for inertia, assuming a constant density for the vehicle shape.

Table - Inertia Properties

Parameter	Description
Uniform Cylinder model for current entries	Defines the weight, length, and radius of the vehicle.
Set up a new Uniform Cylinder Model	Creates a new uniform cylinder model based on a defined radius.
Setup a new Ellipsoid/Cuboid Model	Creates either an elliptic cylinder, an ellipsoid, or a cuboid model based on a defined height and width.