Using Six Degrees of Freedom in Aviator

STK Premium (Air) or STK Enterprise
You can obtain the necessary licenses for this tutorial by contacting AGI Support at support@agi.com or 1-800-924-7244.

This lesson requires an internet connection and version 13.0 of the STK software or newer to complete in its entirety.

The results of the tutorial may vary depending on the user settings and data enabled (online operations, terrain server, dynamic Earth data, etc.). It is acceptable to have different results.

Capabilities covered

This lesson covers the following capabilities and tools of the Ansys Systems Tool Kit® (STK®) digital mission engineering software:

  • STK Pro
  • Aviator

Problem statement

Aircrew and mission planners require analytical tools to simulate real-world aircraft performance, ones which account for variations in airframe characteristics and mission requirements. You are designing a test plan for a high-performance aircraft flying out of Buckley Space Force Base (SFB). During the flight, the pilot will execute various maneuvers to see how they affect the overall performance of the aircraft.

Solution

Use the STK software's Aviator capability to build and simulate the aircraft's maneuvers with a full six degrees of freedom (6DoF), modeling the pilot's inputs to the flight controls with Dynamic Control procedures. Then, use a custom report to analyze how various maneuvers affect the aircraft's flight characteristics, such as stall and recovery speeds and required thrust in high-angle climbs.

What you will learn

Upon completion of this tutorial, you will understand the following:

  • How to use the Aviator Catalog Manager and the Aviator catalog interface to insert mission elements
  • How to model an aircraft mission using the Aviator propagator
  • How to use Aviator tools to define an aircraft and to create and modify phases and procedures of a mission
  • How to use the Dynamic Control Fixed Wing Acceleration performance model
  • How to use Dynamic Control procedures to simulate an aircraft with six degrees of freedom

Creating a new scenario

First, you must create a new scenario and then build from there.

  1. Launch the STK application ().
  2. Click Create a Scenario in the Welcome to STK dialog box.
  3. Enter the following in the STK: New Scenario Wizard:
    4. Option Value
    Name Aviator_DynControl
    Location Default
    Start Default (recommend changing the time to 18:00:00.000 UTCG for daylight)
    Stop + 30 min
  4. Click OK when you finish.
  5. Click Save () when the scenario loads. The STK application creates a folder with the same name as your scenario for you.
  6. Verify the scenario name and location in the Save As dialog box.
  7. Click Save.

Save () often during this scenario!

Using the Aviator Catalog Manager

The STK software's Aviator capability provides a catalog structure for the loading and saving of aircraft, airports, NAVAIDs, runways, VTOL points, and waypoints. Each of these mission elements has an associated catalog in the STK application. The Aviator Catalog Manager is a utility that allows you to view the contents of catalogs, create new items, copy or edit existing items, and search for specific items.

Opening the Aviator Catalog Manager

Open the Aviator Catalog Manager from the Utilities menu.

  1. Select the Utilities menu.
  2. Select Aviator Catalog Manager... ().

Loading navigation data using the Aviator Catalog Manager

ARINC424 data files are the only valid data sources for NAVAID and airport sites. Load a sample ARINC424 data file containing navigation information into the STK application. The data file is included with your STK installation.

If you have completed other Aviator tutorials, you may have already loaded the sample ARINC424 data file into the STK application.

  1. Resize the Aviator Catalog Manager window by extending it out to the right so that you can see more space in the large, blank area.
  2. Expand () Runway ().
  3. Select ARINC424 runways ().
  4. Click the Use Master Data File ellipsis ().
  5. Navigate to <Install Dir>\Data\Resources\stktraining\samples when the Open dialog box appears.
  6. Select the FAANFD18 data file.
  7. Click Open to select the file and to close the Open dialog box.
  8. Click Save when you return to the Aviator Catalog Manager.
  9. Close () the Aviator Catalog Manager.

Inserting an Aircraft object

Insert an Aircraft object, for which you will create a flight profile.

  1. Bring the Insert STK Objects tool () to the front.
  2. Select Aircraft () in the Select An Object To Be Inserted list.
  3. Select Insert Default () in the Select A Method list.
  4. Click Insert....
  5. Right-click on Aircraft1 () in the Object Browser.
  6. Select Rename in the shortcut menu.
  7. Rename Aircraft1 () DynC_Acft.

Using the Aviator propagator

With the Aviator capability, the aircraft's route is modeled by a sequence of curves parametrized by well-known performance characteristics of aircraft, including cruise airspeed, climb rate, roll rate, and bank angle. The precise state of an aircraft at any given time can be computed analytically. To utilize the Aviator capability, you must first set your aircraft to select Aviator as its propagator.

  1. Right-click on DynC_Acft () in the Object Browser.
  2. Select Properties () in the shortcut menu.
  3. Select the Basic - Route page when the Properties Browser opens.
  4. Open the Propagator drop-down list.
  5. Select Aviator.
  6. Click Apply to confirm your selection and to keep the Properties Browser open.
  7. Review the information in the Flight Path Warning dialog box.
  8. Click Optimize STK for Aviator to set the scenario globe reference to Mean Sea Level (MSL) and the Animation mode to X Real Time.

    9. Aviator performs best in the 3D Graphics window when the surface reference of the globe is set to MSL instead of the default reference of WGS84. Likewise, setting the animation mode to X Real Time allows for smoother animation and better data display performance.

  9. Click OK to close the Fight Path Warning dialog box.

Configuring an Aviator mission

The Mission window is used to define the aircraft's route when Aviator is used as the propagator. The Mission window contains three toolbars — Initial Aircraft Setup, Phases of Flight, and Procedures and Sites — that enable you to define the aircraft that you are modeling and to create, modify, and delete phases and procedures.

Creating a custom aircraft model

The buttons on the Initial Aircraft Setup toolbar are used to define the aircraft model that will be used in the mission. An aircraft model defines the physical characteristics of an aircraft, the aircraft's configuration, and the performance models that define how it flies in a given situation. The basic models found in Select Aircraft dialog box are representative of an aircraft type, but not a specific aircraft. It's up to you to customize the model you choose to match actual aircraft characteristics.

  1. Click Select Aircraft () In the Initial Aircraft Setup toolbar.
  2. Right-click on Basic Fighter () in the User Aircraft Models () when the Select Aircraft dialog box opens.

    3. Note that Basic Fighter () is read only (). Read-only items in the Aviator Catalog Manager cannot be modified, so you must duplicate the built-in aircraft model to make any modifications.

  3. Select Duplicate in the shortcut menu.
  4. Right-click on Basic Fighter Copy ().
  5. Select Rename in the shortcut menu.
  6. Rename Basic Fighter Copy () DynC_Fighter.
  7. Select DynC_Fighter () in the User Aircraft Models () list.
  8. Click OK to close the Select Aircraft dialog box.
  9. Click Apply.

Creating a new performance model

The Aircraft Properties provide access to Performance models, which are used to define the behavior of the aircraft in flight. By specifying the performance models to use with each phase of the mission, you can vary the manner in which the aircraft performs, based on the mission's priorities.

  1. Click Aircraft Properties () in the Initial Aircraft Setup toolbar.
  2. Right-click on Acceleration () in the Performance Models list in the DynC_Fighter dialog box.
  3. Select Add New Model Type... in the shortcut menu.
  4. Select AGI DynC Fixed Wing Acceleration Model in the New Types list when the Add New Model Type dialog box opens.
  5. Click OK to confirm and to close the Add New Model Type dialog box.

Using the Dynamic Control Fixed Wing Acceleration performance model

The Dynamic Control Fixed Wing acceleration model provides a force and moment model for Dynamic Control procedures, which implement a simple Fixed Wing model with aerodynamics, propulsion and flight control systems. The Dynamic Control Fixed Wing performance model is comprised of four tabs: Basic, Aerodynamics, Propulsion, and Flight Control. The Basic tab defines the turn rate behavior, climb/descent transitions, attitude transitions, and control authority information. The Aerodynamics and Propulsion tabs allow you to select and define strategies to model attitude and propulsion characteristics. The Flight Control tab allows you to set the control ranges.

Using the FighterAero aerodynamics strategy

The FighterAero strategy model is a generalization of the F-16 model from “Aircraft Control and Simulation: Dynamics, Controls Design, and Autonomous Sysytems" by Brian L. Stevens, Frank L. Lewis, and Eric N. Johnson. It contains a variety of aerodynamic tables, which, for the F-16, are derived from wind tunnel data. This model version is generalized to allow you to supply different tables; however the form of the model is fixed. The idea is that this model is similar to other fighters, but one not altogether different from an F-16.

  1. Select the Aerodynamics tab.
  2. Keep the default strategy setting of FighterAero.

Using the FighterProp propulsion strategy

The FighterProp strategy model is closely modeled from the Stevens F-16. The thrust is primarily computed from a set of three tables, which are indexed by mach and altitude. Through the different models of operation, these tables are interpolated to arrive at the thrust.

  1. Select the Propulsion tab.
  2. Keep the default strategy setting of FighterProp.

When using the Dynamic Control Fixed Wing Acceleration performance model in actuality, careful attention should be taken to ensure the weights and inertial matrices in the chosen aircraft match those of the F-16 fighter aircraft; otherwise, you should update the aerodynamics and propulsion strategies for your chosen aircraft model (wing areas, propulsion, etc.).

Using the FixedWingFlightCtrl strategy

The FixedWingFlightCtrl strategy stores the control ranges; the underlying aerodynamics model uses normalized -1,1 ranges. The strategy also implements any desired autopilot modes.

  1. Select the Flight Control tab.
  2. Look in the Controls panel.

    3. These are the actuators of the flight control. They represent pilot stick control, which, for fixed wing are elevator, aileron, rudder, and throttle. The max deflections for the control surfaces are the max in the positive and negative directions.

  3. Look in the VXF panel.

    4. This field represents autopilot mode. The Course Snap option controls how aggressively the plane turns while in autopilot mode. The MaxBank value comes from the "Basic" tab bank angle.

  4. Click Save.
  5. Click Close to close the DynC_Fighter dialog box.
  6. Click Apply.

Linking the performance model to the mission phase

Phases are the basic units of an aircraft's mission, and serve as containers for the procedures that define the aircraft's actions. Every mission must have at least one phase of flight and can have as many phases as you desire. You can select a specific set of performance models to use with each phase, allowing you to perform one mission with multiple performance characteristics. For this tutorial, you will use only one phase, linked to the Dynamic Control Fixed Wing Acceleration performance model you selected.

  1. Right-click on Phase 1 in the Mission List.

    2. The Mission List provides an overview of the mission by listing each of the mission phases and the procedures within them, in the order in which they will be executed. Both phases and procedures are displayed in the Mission List.

  2. Select Phase Properties ... () in the shortcut menu.
  3. Right-click on Acceleration in the Model Type list when the Phase 1 properties dialog box opens.
  4. Select Link to Catalog... in the shortcut menu.
  5. Select AGI DynC Fixed Wing Acceleration Model when the Link to Catalog (Acceleration) dialog box opens.
  6. Click OK to confirm and to close the Link to Catalog (Acceleration) dialog box.
  7. Click OK to close the Phase 1 properties dialog box.
  8. Click Apply.

Changing the aircraft's configuration

The Configuration window is used to define the aircraft's fuel and payload configuration.

Updating the aircraft's basic configuration

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.

  1. Click Configuration () in the Initial Aircraft Setup toolbar.
  2. Select the Basic tab when the Aircraft Configuration dialog box opens.
  3. Enter 19100 lb in the Empty Weight field.

    4. This is where you add payload weight. In this instance, the weight will account for the pilot, instructor, any passengers and baggage.

  4. Note the Max Landing Weight value of 35500 lb.
  5. Note the Total Weight value of 38100 lb.

    6. This is the empty weight plus the default fuel weight of DynC_Acft.

Updating the aircraft’s fuel configuration

The Stations tab is used to define the aircraft's internal fuel tanks, stations, and external fuel tanks that are attached to the stations.

  1. Select the Stations tab.
  2. Select Internal Fuel ().
  3. Enter 7000 lb in the Capacity field.

    4. This is the internal fuel capacity of the aircraft.

  4. Enter 3000 lb in the Initial state field.

    5. You will start with 3,000 pounds of fuel. At the end of the simulation, you will analyze data to determine if you require less or more fuel for the mission.

  5. Click Apply to confirm your fuel changes.
  6. Click OK to confirm your changes and to close the Aircraft configuration dialog box.
  7. Click Apply.

Updating the Mission Profile

The Mission Profile can display a variety of data describing the mission. The default profile displays the aircraft's altitude relative to its downrange distance, but the graph can be customized to display any Flight Profile data provider with respect to time or downrange distance. The segment of the profile that represents the procedure that is currently selected in the Mission List is displayed as a bold line.

  1. Right-click in the Mission Profile.
  2. Select Profile Options/Properties... in the shortcut menu.
  3. Select the Secondary Y Axis check box in the Profile Options/Properties dialog box.
  4. Select True Air Speed in the Secondary Y Axis list.
  5. Click OK to confirm your selection and to close the Profile Options/Properties dialog box.
  6. Click Apply.

Building the aircraft's mission

The Aviator capability is built upon the concept of an aircraft's mission, as opposed to a mere point-to-point route. You have set up and defined the aircraft model, the singular phase of the mission, and its associated Dynamic Control Fixed Wing acceleration performance model. Now, insert and define the sites and procedures that the aircraft will execute for its mission. Sites define the locations of the procedures and types of procedures that are available to select. Procedures define the actions the aircraft executes. There are many procedure types that an aircraft can perform, though the exact selection of procedure types available is dependent on the currently selected site and the immediately previous procedure. A procedure is executed using the performance models specified for the phase that it is contained within.

Using a Dynamic Control Trim Point

Insert a Dynamic Control Trim Point () site to use a Dynamic Control procedure as the first procedure in a mission. It is the simple placement of the aircraft in space, with a course, velocity, flight path angle, and turn rate.

  1. Select the Basic – Route page.
  2. Click Insert Procedure After () in the Procedures and Sites toolbar.
  3. Select DynCTrimPoint () in the Select Site Type list in the Site Properties dialog box.
  4. Enter the following parameters in the State panel:
    5. Option Value
    Latitude 39.6 deg
    Longitude -104.68 deg
    Altitude 15000 ft
    Course 151.4 deg
    TAS True Airspeed: the speed that the aircraft is moving relative to the airmass that it is flying in. 400 nm/hr
  5. Click Next >.

Inserting a Dynamic Control procedure

The Dynamic Control procedure type for Aviator extends the concepts in a Basic Maneuver procedure to a full 6DoF vehicle, controlled by elevator, aileron, rudder, and throttle. With a Dynamic Control procedure, the aircraft trims into the previous flight condition, including the speed, turn rate and flight path angle. The attitude is set to the previous flight condition and the controls are set in the trim position. If the trim is stable, the aircraft might have a small initial transit, but it will then fly the trim trajectory.

You already activated a Dynamic Control Fixed Wing Acceleration performance model to use this procedure. This performance model can also be used for other procedures such as Basic Maneuver, which is why you set it for the entire phase of your mission. In this case, the performance model uses a trim algorithm to create the aeropropulsion data based directly on the same unit which flies the Dynamic control.

In your first Dynamic Control procedure, the pilot will trim the aircraft and fly down range for 10 nautical miles

  1. Select DynamicControl () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Enter Trim 10 Nautical Miles in the Name field.
  3. Leave the default Trim Hold strategy.
  4. Set the following parameters in the Basic Stop Conditions panel:
    5. Option Value
    Fuel State Cleared
    Time of Flight Cleared
    Downrange 10 nm
  5. Click Finishto confirm your selections and to close the Procedure Properties dialog box.
  6. Click Apply.

Inserting an End of Previous Procedure site type

In this instance, you want to switch to a Dynamic Control procedure at the end of your previous procedure. A Dynamic Control procedure can follow either a Dynamic Control Trim Point site or End of Previous Procedure site for most Aviator procedures.

  1. Click Insert Procedure After () in the Procedures and Sites toolbar.
  2. Select End of Previous Procedure () in the Select Site Type list in the Site Properties dialog box.
  3. Click Next >.

Using the VXF strategy

The pilot will turn the aircraft to a heading The direction that the aircraft is pointing. of 90 degrees, maintain its current altitude, and increase its speed to 600 nautical miles per hour.

  1. Select DynamicControl () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Enter Fly 90 Degrees in the Name field.
  3. Open the Strategy drop-down list.
  4. Select VXF.

Setting the VXF control parameters

Currently, the aircraft is flying at a speed of 400 nautical miles per hour. You want to increase speed to 600 nautical miles per hour and turn to a heading of 90 degrees. Use the Velocity, Course, Flight Path Angle (VXF) controller, which uses nonlinear dynamic inversion to attain these three parameters, and enter the changes as a series of time points. The points are interpolated when Linear Interpolation is selected; otherwise, they are taken as step commands.

  1. Enter Time: [5.00; ] in the Time field in the VXF Time Series Panel.

    2. The Time VXF control is a series of increasing time points. The time points are not checked against the procedure duration, but are only used when they fall in range. This begins your aircraft's maneuver five (5) seconds after the end of the previous maneuver.

    Be sure to include the space following the semicolon (;) in the expression.

  2. Enter [600.00; ] in the Velocity (nm/hr) field.

    3. The Velocity VXF control is an ECF velocity to achieve corresponding to the time series. Your aircraft will begin to increase its speed to 600 nautical miles per hour, based on its performance characteristics.

  3. Enter [90.00; ] in the Course (Deg) field.

    4. The Course VXF control is a course to achieve corresponding to the time series. Your aircraft will turn to a course of 90 degrees based on its performance characteristics.

  4. Enter [0.00; ] in the Flight Path (Deg) field.

    5. The Flight Path VXF control is a flight path angle to achieve corresponding to the time series. Your aircraft will remain in level flight.

    dynamic control properties

This is an introduction to using dynamic control properties. You only used one set of times in the VFX Time Series panel. However, you could insert multiple times and maneuvers. You will try this later in the scenario.

Setting the basic stop condition

Give the aircraft time to increase its speed.

  1. Set the following parameters in the Basic Stop Conditions panel:
    2. Option Value
    Fuel State Cleared
    Time of Flight 00:01:00.000 HMS
    Downrange Cleared
  2. Click Finish.
  3. Click Apply.

Inserting an End of Previous Procedure site type

Insert another End of Previous Procedure site for your next Dynamic Control procedure.

  1. Click Insert Procedure After () in the Procedures and Sites toolbar.
  2. Select End of Previous Procedure () in the Select Site Type list in the Site Properties dialog box.
  3. Click Next >.

Switching to the Trim hold strategy

Roll the aircraft prior to climbing with another Dynamic Control procedure using the Trim hold strategy. This strategy will hold the trim values so the initial dynamic state is maintained. In addition, it can put doublets into the system at a given time.

  1. Select DynamicControl () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Enter Use Lateral Doublet in the Name field.
  3. Use the default Trim Hold strategy.
  4. Select the Lateral option in the Doublet panel.
  5. Enter 15 sec in the Length field.
  6. Set the following in the Basic Stop Conditions panel:
    7. Option Value
    Fuel State Cleared
    Time of Flight 00:00:10.000 HMS
    Downrange Cleared
  7. Click Finish.
  8. Click Apply.

Inserting an End of Previous Procedure site type

Use an End of Previous Procedure site for your next Dynamic Control procedure.

  1. Click Insert Procedure After () in the Procedures and Sites toolbar.
  2. Select End of Previous Procedure () in the Select Site Type list in the Site Properties dialog box.
  3. Click Next >.

Inserting a Dynamic Control procedure

At the bottom of the roll and decent, the pilot will climb, then descend while turning the aircraft to a heading of 340 degrees.

  1. Select DynamicControl () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Enter Multiple Maneuvers in the Name field.
  3. Open the Strategy drop-down list.
  4. Select VXF.
  5. Enter the following in the VXF Time Series panel:
    6. Option Value
    Time [2.00, 30.00, 60.00; ]
    Velocity (nm/hr) [700.00, 600.00, 500.00; ]
    Course (Deg) [0.00, 340.00, 340.00; ]
    Flight Path (Deg) [50.00, 0.00, -5.00; ]

    multiple maneuvers

    This is an example of a series of time steps.

  6. Set the following in the Basic Stop Conditions panel:
    7. Option Value
    Fuel State Cleared
    Time of Flight Cleared
    Downrange 20 nm
  7. Click Finish.
  8. Click Apply.

Inserting an End of Previous Procedure site type

Use an End of Previous Procedure site for your next Dynamic Control procedure.

  1. Click Insert Procedure After () in the Procedures and Sites toolbar.
  2. Select End of Previous Procedure () in the Select Site Type list in the Site Properties dialog box.
  3. Click Next >.

Switching to trim hold

Trim the aircraft to turn and slowly descend for landing.

  1. Select DynamicControl () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Enter Trim Hold Yaw in the Name field.
  3. Leave the default Trim Hold strategy.
  4. Select Yaw in the Doublet panel.
  5. Enter 45 sec in the Length field.
  6. Set the following in the Basic Stop Conditions panel:
    7. Option Value
    Fuel State Cleared
    Time of Flight 00:01:00.000 HMS
    Downrange Cleared
  7. Click Finish.
  8. Click Apply.

Selecting the landing runway

Return to base to perform a touch-and-go landing.

  1. Select Insert Procedure After () in the Procedures and Sites toolbar.
  2. Select Runway from Catalog () in the Select Site Type list in the Site Properties dialog box.
  3. Enter Buckley in the Filter field.
  4. Select the Enter key.
  5. Select BUCKLEY AFB 14 32 () under ARINC424 runways ().
  6. Click Next >.

Inserting a Landing procedure

A Landing procedure brings an aircraft down from the air to a runway site. Using the Intercept Glideslope approach mode, the aircraft will perform a landing following VFR flight rules; it will use a basic point-to-point methodology to fly to the Initial Approach Fix Range and then descend to landing along the glideslope.

A touch-and-go landing procedure will end the Landing procedure at wheels down. You can then follow this Landing procedure with a Takeoff procedure to simulate a touch-and-go landing. The aircraft will, if needed, accelerate to the takeoff speed as specified in the performance model as part of the subsequent Takeoff procedure.

  1. Select Landing () in the Select Procedure Type list in the Procedure Properties dialog box.
  2. Set the following options:
    3. Option Value
    Name Buckley Runway
    Approach Mode Intercept Glideslope
    Use runway heading 144 Mag 151 True Selected
    Landing Options - Approach Fix Range 2 nm
    Landing Options - Runway Altitude Offset 10 ft
    Landing Options - Use Terrain for Runway Altitude Selected
    Landing Options - Touch and Go Selected
    Enroute Options - Use Max Speed When Computing Turn Radii Selected
  3. Open the drop-down list in the Enroute Cruise Airspeed panel.
  4. Select Arrive on landing airspeed (gradual change).
  5. Click Finish.
  6. Click Apply.

Landing is a standard Aviator procedure. You can easily mix and match Dynamic Control procedures with non-dynamic Aviator procedures, such as Basic Maneuvers, Simple Turns, and Holding patterns, to suit your mission requirements.

Taking off after the touch and go

To complete the touch-and-go landing, you need to take off from the Buckley runway.

  1. Click Insert Procedure After () in the Procedures and Sites toolbar.
  2. Note that End of Previous Procedure () is the only available site type, since you selected the Touch and Go landing option for your Landing procedure.
  3. Click Next > in the Site Properties dialog box.

Selecting the Takeoff procedure

Because you selected Touch and Go for your Landing procedure, the only available procedure is a Takeoff procedure. A Takeoff procedure launches an aircraft from a runway site into the air.

  1. Set the following options:
    2. Option Value
    Name Takeoff from Buckley Runway
    Runway Altitude Offset 10 ft
    Use Terrain for Runway Altitude Selected
  2. Click Finish.
  3. Click Apply.
  4. Review the Mission Profile for situational awareness.

Final Mission Profile

Checking fuel usage

At this point, you can continue to fly your mission. You need to keep an eye on your fuel usage. You could create a report, but you can find useful information while using Aviator.

  1. Right-click on Takeoff from Buckley Runway () in the Mission List.
  2. Select Profile Data at Final State... in the shortcut menu to open the Profile Data window.

    3. The Profile Data dialog box displays mission data at the point in the mission profile at which it is invoked from the right-click command menu. The window displays all of the Flight Profile data providers, but can be sorted or filtered using the drop-down list at the top of the window.

  3. Scroll down and locate both the Fuel Consumed and Fuel State data providers.

    4. Fuel Consumed is how much fuel you've used and Fuel State is how much fuel remains. You can use the information to make sure at the beginning of the mission you have enough fuel to fly your entire mission.

  4. Close the Takeoff from Buckley Runway dialog box.

Analyzing flight data

An important reason to use six degrees of freedom with the Aviator capability is to obtain analytical data on your aircraft. You will create a custom report focusing on pilot stick control.

Creating a custom report

Create a new report style for your custom report.

  1. Right-click on DynC_Acft () in the Object Browser.
  2. Select Report & Graph Manager... () in the shortcut menu.
  3. Select the My Styles () folder in the Styles panel when the Report & Graph Manager opens.
  4. Click Create new report style () in the Styles toolbar.
  5. Enter 6DoF Analysis as the new report name.
  6. Select the Enter key to set the new report name and to open the report's properties.

Selecting data providers and elements

The Flight Profile By Time data provider has the elements required for your analysis. Flight data is sampled using a constant time step between grid points. You will use the following data provider elements in your custom report:

    • Time: The time
    • Aileron: The roll axis control input
    • Elevator: Longitudinal axis control input
    • Rudder: Yaw axis control input
    • Throttle (%): The percentage of the maximum thrust required to maintain the flight condition
    • True Air Speed: The magnitude of the velocity of the vehicle, where the velocity is measured as observed from the vehicle's central body fixed coordinate system
    • Altitude: The altitude value (that is, the magnitude of the relative position vector between the object and its detic subpoint)
    • Fuel Consumed: The amount of fuel consumed during the mission in pounds. At mission start, the value is zero.

This report style is only available for Aviator-propagated vehicles.

  1. Select the Content page when the Properties Browser opens.
  2. Expand () the Flight Profile By Time () data provider in the Data Providers list.
  3. Move () the following data provider elements () to the Report Contents list in the order shown:
    • Time
    • Aileron
    • Elevator
    • Rudder
    • Throttle (%)
    • True Air Speed
    • Altitude
    • Fuel Consumed
  4. Click OK to confirm your selections and to close the Properties Browser.

Adjusting the report's time properties

Adjust the time properties of the report to analyze the aircraft in one-second increments.

  1. Select the Specify Time Properties option in the Time Properties panel.
  2. Select the Use step size / time bound option.
  3. Enter 1 sec in the Step size field.

Generating your custom report

Now that you have added the data providers to your report contents and adjusted the step size, generate and review the report.

  1. Select 6DoF Analysis () in the My Styles () folder.
  2. Click Generate....
  3. Scroll through the report.
  4. Close the report and the Report & Graph Manager when finished.

Adding a dynamic data display to the 3D Graphics window

Update your Aircraft object's Data Display properties to display dynamic data for the flight in the 3D Graphics window. This feature is useful when presenting information that requires both visual and textual data. You can either use the default data or add the data from a custom report to the data display list. In this case, you'll display the data from your custom 6DoF Analysis report.

  1. Return to DynC_Acft's () Properties ().
  2. Select the 3D Graphics – Data Display page.
  3. Click Add....
  4. Select 6DoF Analysis in the Styles list in the Add a Data Display dialog box.
  5. Click OK to confirm your selection and to close the Add a Data Display dialog box.
  6. Open the Font Size drop-down list in the appearance panel.
  7. Select Medium.

    8. This setting is user defined for clarity. If the font is too small or too large on your monitor, select a setting that looks good to you.

  8. Click Apply.

You can now view the custom report you created, dynamically, in the 3D Graphics window when you animate the scenario.

Viewing the roll and climb

You can view the entire flight from the Dynamic Control Trim Point until your touch-and-go landing. You can narrow your visualization to each procedure in the Mission List, too. One of the more interesting maneuvers is when you increase speed and use the lateral doublet.

  1. Return to DynC_Acft's () Properties ().
  2. Right-click on Fly 90 degrees () in the Mission List.
  3. Select Set Animation Time in the shortcut menu.
  4. Bring the 3D Graphics window to the front.
  5. Right-click on DynC_Acft () in the Object Browser.
  6. Select Zoom To in the shortcut menu.
  7. Configure your view so that you are behind DynC_Acft ().
  8. Click Start () in the Animation toolbar to watch your lateral doublet maneuver and the follow-on multiple maneuvers.

    9. the aircraft rolls, dives, and climbs

  9. When finished, click Reset () to reset your scenario.

Saving your work

Clean up your workspace and close out your scenario.

  1. Close any open windows except for the 2D and 3D Graphics windows.
  2. Save () your work.
  3. Close the scenario when you are finished.

Summary

This scenario was designed to show you how to configure an Aircraft object using Aviator and applying six degrees of freedom to your simulation. You started the simulation using a Dynamic Control Trim Point. You switched to dynamic control using the VXF strategy to increase the aircraft's speed and change its course. Next, you applied a Trim Hold strategy using a Lateral Doublet to roll the aircraft and descend. Switching back to a VXF strategy, you created multiple maneuvers, changing speed, course, and flight path angles. You placed the aircraft back into a Trim Hold to line up for a landing approach, then performed a touch-and-go landing at Buckley SFB. Lastly, you created a custom report that focused on pilot stick control.