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.

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 STK Capabilities:

  • STK Pro
  • Aviator

Problem Statement

Engineers and operators require a quick way to model an aicraft's flight from takeoff to landing.

Solution

Use STK's Aviator capability to model an aircraft's performance characteristics and create a short takeoff from a cleared airstrip to a target and return to the airstrip and land.

This lesson can be completed with or without an internet connection. In this lesson, you will be required to enter multiple latitudes and longitudes. Please keep in mind that Place, Target, and Facility objects can be simply inserted using point-and-click in the 2D Graphics window or employing the 3D Object Editing Tool in the 3D Graphics window. Typing all the data in this lesson ensures you obtain the same data and feedback.

Video Guidance

Watch the following video. Then follow the steps below, which incorporate the systems and missions you work on (sample inputs provided).

Create a Scenario

Start by creating a scenario.

  1. Open STK and click the Create a Scenario button.
  2. Enter the following in the New Scenario Wizard:
    3. Option Value
    Name STK_Aviator
    Location C:\Users\<username>\Documents\STK 12\
    Start 1 Jul 2016 16:00:00.000 UTCG
    End + 6 hr
  3. When you finish, click OK .

Save Often!

Scenario Level Properties

Disable Terrain Server.

  1. Select STK_Aviator () in the Object Browser.
  2. Click Properties ().
  3. Select the Basic - Terrain page.
  4. Disable the Use terrain server for analysis option.

Enable Surface Lines

Surface Lines can be displayed in the 3D Graphics window on the surface of the central body when terrain data is available.

  1. Browse to the 3D Graphics - Global Attributes page.
  2. In the Surface Lines field, set the On Terrain field to On.
  3. Click  OK to apply changes and dismiss the Properties Browser.

3D Graphics Window Properties

To help you when orienting your view in the 3D Graphics window, you can have object labels "float" above the terrain and use an embedded compass.

  1. Bring the 3D Graphics window to the front.
  2. Click the Properties () button in the 3D Graphics toolbar.
  3. On the Details page, locate the Label Declutter section and select the Enable check box.
  4. Browse to the Annotation page.
  5. Locate the Compass section and select the Show check box.
  6. Click OK .

    7. When you return to the 3D Graphics window, in the lower left corner of the window there is a small compass. When you add objects to the scenario, the object labels will float above the terrain.

Add Terrain for Analysis and Visualization

You can add analytical and visual terrain using Globe Manager.

  1. Bring the 3D Graphics window to the front and click Globe Manager ().
  2. In Globe Manager, extend the Add Terrain/Imagery () menu.
  3. Select Add Terrain/Imagery (Add Terrain/Imagery button).
  4. Click the ... button.
  5. Browse to <STK Install directory>\Data\Resources\stktraining\imagery.
  6. Click OK .
  7. Select the PtMugu_ChinaLake.pdtt file.
  8. Click Add .
  9. Click Yes on the Use Terrain for Analysis dialog.

Create an Airstrip

You do not have an airfield or airstrip that can be loaded from the ARINC424 runways database (FAANFD18). If you do not have Bing Maps or a satellite image of a cleared airstrip, a simple way to build one on top of the terrain is by using an Area Target object.

You will be outlining an improvised airstrip and this technique could be used to outline an airstrip in the middle of a desert. If you do not have an internet connection, Bing Maps, or a satellite picture of the airstrip, outlining it with an Area Target object is a good way to get situational awareness of the airstrip's size and location. The Area Target can be precisely drawn if you have the coordinates or you can click and draw using the 2D Graphics window or the 3D Object Editing tool.

  1. Insert a Area Target () object using the Insert Default method.
  2. Rename the Area Target object "Airstrip".
  3. Open Airstrip's () properties ().
  4. On the Basic - Boundary page, add the following points (copy and paste if able):
    5. Latitude Longitude
    35.74833 deg -117.63113 deg
    35.74835 deg -117.63107 deg
    35.73713 deg -117.62753 deg
    35.73711 deg -117.6276 deg
  5. Click Apply .

Make the airstrip easier to see in the 2D Graphics window.

  1. Browse to the 2D Graphics - Attributes page.
  2. If desired, change the Color field.
  3. In the Line Width field, select the heaviest line width.
  4. Click OK .
  5. Bring the 3D Graphics window to the front and Zoom To Airstrip.
  6. Use your mouse to obtain a good view of Airstrip.

3D Graphics Airstrip View

Create a Navigation Point

When you enter the target area, the navigation point will be used to line up the circular flight orbit around a ground target.

  1. Insert a Place () object using the Define Properties () method.
  2. Enter the following values on the Basic - Position page:
    3. Option Value
    Latitude 34.8977 deg
    Longitude -117.6446 deg
  3. Click OK .
  4. Rename the Place object "NavPoint".

Add a Target

This is a practice target that the aircraft will use to calibrate its instruments.

  1. Insert a Target () object using the Define Properties () method.
  2. Enter the following values on the Basic - Position page:
    3. Option Value
    Latitude 34.8979 deg
    Longitude -117.6857 deg
    Height Above Ground 1 m
  3. Browse to the 3D Graphics - Model page.
  4. Locate the Model section and select the Show check box.
  5. In the Detail Thresholds section, change Details - Maximum Viewing Distance - All by moving the slider all the way to the right (maximum distance).
  6. Click OK .
  7. Rename the Target object "GndTarget."

3D Aviator Editing

Add an Aircraft object to the scenario and then edit its performance models using the Aviator Editing toolbar. This toolbar allows you to define an aircraft and its procedures in the 3D Graphics window. When airfield or airstrip data does not exist in a file format, this procedure is the most accurate means of building takeoff and landing procedures. In this scenario, use a combination of the Aviator Editing toolbar and object properties. The aircraft will have a light fuel load due to the short takeoff required at the airstrip.

  1. Insert an Aircraft () object using the Insert Default () method.
  2. Rename the Aircraft object "TestFlight".

Enable the 3D Aviator Editing Tool

Enable the 3D Aviator Editing tool using the following steps.

  1. Extend the View menu.
  2. Extend the Toolbars menu and select the 3D Aviator Editing tool.

3D Aviator Editing Toolbar

Zoom To the Aircraft

  1. Focus on the 3D Graphics window and Zoom To Airstrip.
  2. Center your view on the center of the runway by using the Area Target object's centroid.
  3. Select Aircraft/TestFlight in the 3D Object Editing toolbar 3D Editing Object drop-down list.
  4. Click the Object Edit Start/Accept () button to start the 3D Object Editing tool.
  5. Click the Switch to Aviator button on the 3D Aviator Editing tool.
  6. Click OK when the warning window pops up.

Select the Aircraft Type

First you will select the aircraft type and then edit its performance models.

  1. In the 3D Aviator Editing toolbar, click the Select Aircraft () button.
  2. When the Select Aircraft window opens, right-click on Basic Military Transport.
  3. Select Duplicate.
  4. Select Basic Military Transport Copy and rename it "TestFlight."
  5. Click OK .

Performance Models

Change a couple of performance models for familiarization of the GUI.

  1. In the 3D Aviator Editing toolbar, click the Aircraft Catalog for Current Aircraft () button.

    2. You can browse through the Basic Performance models to familiarize yourself with their Built-in Models. There are Advanced Performance models that can be added to the scenario. But, in this tutorial, use Basic Performance Models.

  2. In the Performance Models: section, select the Acceleration Built-In Model.
  3. Select the Bank Angle: radio button.
  4. Set the Bank Angle: to 20 deg.
  5. In the Performance Models: section, select the Cruise Built-In Model.
  6. Change the Default Cruise Altitude: to 10000 ft.
  7. Click Save and then click Close .

Adjust the Position of the Aircraft

To line the aircraft up with the runway for the Takeoff Procedure:

  1. Make sure you are zoomed into the Airstrip. North on the compass in the corner should be pointing up.

    2. Use the 3D Object Editing and 3D Aviator Editing toolbars to create a flight route to include takeoff and landing. STK can utilize DAFIF or the Digital Aeronautical Flight Information Files.

  2. Return to the 3D Aviator Editing toolbar.
  3. Choose Runway in the Aviator Site pull down menu.
  4. Choose Takeoff in the Aviator Procedure pull down menu.
  5. Using the mouse, shift-click on Airstrip's centroid.
  6. Scroll out far enough to see one red ball at each end of the Takeoff procedure.
  7. Place the cursor on the Takeoff @ Runway - WheelsRelease red ball (most likely the red ball to the west), hold down the left mouse button, and drag and drop the red ball at the runway threshold. The runway threshold is the north end of the airstrip.

Runway Threshold

Modify the Aircraft's Runway Placement

Depending on how precise your clicks were in the 3D Graphics window, the Aircraft object's model could be above or below the surface of the map. Either way, instruct the Aircraft object to follow the terrain during the takeoff roll. Furthermore, compensate for the wheels to visually ensure that the wheels are touching the runway.

  1. Click the Modify Procedure () button in the 3D Aviator Editing tool.
  2. Make the following changes in the Takeoff Properties pop up window:
    3. Option Value
    Runway Altitude Offset: 15 ft
    Use Terrain for Runway Altitude On
  3. Click OK .
  4. Click the Object Edit Start/Accept () button to accept the changes.
  5. Zoom to the TestFlight object.
  6. If required, use the 3D Object Editing tool and the 3D Aviator Editing tool to continue to adjust the takeoff procedure until satisfied with the Aircraft object's alignment.

Proper Alignment

Save Airstrip to Catalog

Once you are satisfied with the takeoff procedure, save the runway to a catalog. You can use the cataloged runway when creating the landing procedure.

  1. In the 3D Graphics Editor toolbar, select Aircraft/TestFlight
  2. Click the Object Edit Start/Accept button.
  3. Click the Modify Site () button in the 3D Aviator Editing toolbar.
  4. When the Runway Properties window opens, change Name: to "Airstrip."
  5. Click Add To Catalog
  6. Click OK to close the Add Successful pop up window.
  7. Click OK to close the Runway Properties window.
  8. In the 3D Graphics Editor toolbar, click the Object Edit Start/Accept button to save your changes.

Aircraft Specifications

Since the aircraft's takeoff roll will be short it will not take a full load of fuel. It's important to set the correct fuel load and aircraft weight.

  1. Open TestFlight's () properties ().
  2. In the Initial Aircraft Setup toolbar, click Configuration.
  3. Make the following changes in the Basic tab:
    4. Option Value
    Empty Weight: 95000 lb
    Max Landing Weight: 155000 lb
  4. Select the Stations tab.
  5. Select Internal Fuel and make the following changes:
    6. Option Value
    Initial state: 20000 lb
    Capacity: 60000 lb
  6. Click Apply and then click OK .
  7. Click Apply in TestFlight's () properties () window.

Set the Reference to Mean Sea Level

Aviator performs best in the 3D Graphics window when the surface reference of the globe is set to Mean Sea Level.

  1. Click Apply. You will receive a warning message.

    When you click Apply or click OK to close the properties window of an Aviator object with the surface reference set to WGS84, this warning message will display. It is highly recommended that you set the surface reference as indicated before working with Aviator.

  2. Click Optimize STK for Aviator and click OK.

Mission Winds

The Wind and Atmosphere tool allows you to simulate wind and atmospheric conditions for the scenario, a mission, a specific procedure, or a group of multi-selected procedures. Since this planning session is not taking place today, you can set up conditions based on historical values for the training area. The airstrip is located in a desert area. It's important that the correct temperature is reflected in this scenario.

  1. On the TestFlight properties window, find the Initial Aircraft Setup toolbar and click Mission Wind Model.
  2. In the Model Type field, select Constant Bearing/Speed.
  3. Make the following changes:
    4. Option Value
    Wind Bearing: 200 deg
    Wind Speed: 20 nm/hr
  4. In the Atmosphere section, select the Non Standard Surface Conditions check box.
  5. Change Sea Level Temperature: to 110 degF.
  6. Click OK .
  7. Click OK again to save your changes and to close TestFlight's () properties ().

Fly to the Target

TestFlight flies from the airfield to the target, makes one circle around the target, and then returns to land at the airstrip.

  1. Return to the 3D Object Editing tool, select Aircraft/TestFlight, and click the Object Edit Start/Accept button.

    2. Make sure you can see NavPoint in the 3D Graphics window.

  2. In the Aviator Site drop down menu, select STK Static Object .
  3. In the Aviator Procedure drop down menu, select Holding - Circular.
  4. In the 3D Graphics window, Shift - Click on NavPoint.
  5. Click Modify Procedure ().
  6. Make the following changes:
    7. Option Value
    Hold Cruise Airspeed Minimum Airspeed
    Enroute Cruise Airspeed Other Airspeed

    Click OK on the pop-up warning message
    Enroute Cruise Airspeed - Airspeed:

    Select TAS True Airspeed: the speed that the aircraft is moving relative to the airmass that it is flying in. from the drop down menu.

    200 nm/hr
  7. Click Apply .
  8. In the Hold Options field, set the following:
    9. Option Value
    Bearing: 0 deg
    Range: 0 nm
    Diameter: 4 nm
    Use Alternate Entry Points Off
    Turn Direction: Outbound Left Turn
  9. Click OK .
  10. Return to the 3D Graphics Editor and click the Object Edit Start/Accept button.

In order to fly a four (4) nautical mile diameter holding pattern, you needed to slow down entering the pattern and then slow down some more to put instruments on the target. The key here was to ensure the left side of the plane is pointing at the target. The bearing was the direction into the holding pattern and the range of zero nautical miles meant the aircraft entered the pattern as soon as the navigation point was reached. Disabling alternate entry points ensures that the pattern began at the navigation point. There are multiple ways to accomplish the task; this was just one way.

Return and Land at the Airstrip

TestFlight leaves the holding pattern and returns to base to land.

  1. Zoom to Airstrip.
  2. Return to the 3D Object Editing tool, select Aircraft/TestFlight, and click the Object Edit Start/Accept button.
  3. In the 3D Aviator Editing toolbar, click the Next Procedure () button.
  4. Change the Aviator Site to Runway from Catalog.
  5. Change the Aviator Procedure to Landing.
  6. Shift-click on Airstrip's center point.
  7. Click the Modify Procedure () button in the 3D Aviator Editing Tool.
  8. In the Landing Properties window, make the following changes:
    9. Option Value
    Approach Mode: Intercept Glideslope
    Runway Heading The direction that the aircraft is pointing. Use runway heading 153 Mag 166 True (Headwind)
    Runway Altitude Offset: 15 ft
    Use Terrain for Runway Altitude On
  9. Click OK .
  10. Return to the 3D Object Editing tool and click the Object Edit Start/Accept () button.

Run the Flight Animation

  1. Zoom to TestFlight ().

    2. TestFlight is lined up for a takeoff roll, flies to the target area, and lands back at the airstrip.

  2. Use the Animation toolbar to view the flight. Notice how the cross wind affects the aircraft.
  3. When you are finished, reset () the scenario.

Create a Custom Report

Create a report that analyzes the TestFlight's fight profile. The Flight Profile by Time report is a good report that provides important data such as Down Range distances and how much fuel the aircraft has consumed. As with all reports, you can customize the report with your own data.

  1. In the Object Browser, right-click on TestFlight () and select the Report & Graph Manager ().
  2. In the Styles list, right-click on the Flight Profile by Time report and select Properties ().
  3. In Report Contents field, remove Flight Profile By Time-Vertical Speed and Flight Profile By Time-Ground Speed
  4. Select Flight Profile By Time-Altitude-Altitude.
  5. In the Data Providers - Flight Profile By Time, select Altitude AGL.
  6. Move () Altitude AGL to the Report Contents field under Flight Profile By Time-Altitude-Altitude.
  7. Click OK .
  8. Click OK to close the warning message.
  9. In the Styles list, expand My Styles.
  10. Rename your report My Flight Profile by Time.
  11. Generate the report and view the data.
  12. When you are finished, close the report and the Report & Graph Manager.

Embed the Report in the 3D Graphics Window

You can embed the My Flight Profile by Time data in the 3D Graphics window. This is a great technique to use for briefings and making movies.

  1. Open TestFlight's () properties ().
  2. Browse to the 3D Graphics - Data Display page.
  3. Click the Add... button.
  4. In the Add a Data Display pop up window, select My Flight Profile by Time and click OK .
  5. In the Appearance section, change Font Size: to Medium.
  6. Click OK .

    7. In the upper left corner of the 3D Graphics window, you can see a dynamic display of UAV's flight profile.

Run the Flight Animation

  1. Bring the 3D Graphics window to the front.
  2. Zoom to TestFlight ().
  3. Click the Play () button in the Animation toolbar.
  4. When you are finished, click the Reset () button.
  5. Save () the scenario.