Stratofier User Manual

The instructions on this page relate to version and will likely lag behind the current version. There is no guarantee the screenshots will match the current version but I’ll make every effort to keep them up to date.

Stratofier began life as Rosco, then RoscoPi before being rebranded for publishing to GooglePlay as an Android app. It began as a simple Android-based display app for the Stratux ADS-B receiver with an AHRS daughter card (see for details). It was then ported to display directly from the HDMI port on the RaspberryPi the Stratux is based on, then those improvements were ported back to Android. All current development is for the Android platform. After a lot of testing, although the touchscreen connected to the RaspberryPi is a nice custom option, the screens on even older phones and tablets are vastly superior to any inexpensive touchscreen. The Android version is as simple as downloading from the Google Play Store and connecting your phone/tablet to the Stratux and that’s it.

Main Screen

The main screen displays all of the available data streaming from the Stratux receiver. If your Stratux does not have an AHRS daughter card, the attitude will remain stationary and any data derived from those sensors won’t update.

Speed on the left – important note here – this IS NOT air speed if you are using it with the Stratux alone. In that scenario it is GPS derived ground speed since the Stratux does not have access to a bonafide pitot-static sensor. If you are using it with a BADASP sensor platform typically mounted under one of the wings, this IS airspeed. When you are using Stratofier with a BADASP, you will also see the GPS-derived ground speed under the airspeed indication.

The display is laid out similar to many glass panel AHRS displays. It originally tried to mimic the Garmin G300 but it has strayed somewhat from that over time as features have been added.

On the right is the altitude and vertical speed indicators.

The attitude occupies the top half of the display and works like any other attitude indicator. If you are using a BADASP the orientation is derived from the outside sensor, otherwise it is derived from the Stratux. They should both be close to identical however.

The roll indicator displays from 0 to 60 degrees left and right and also behaves like many other glass panel displays.

The heading indicator is extremely large for a reason. It also doubles as a traffic vector display which is also configurable as how much airspace around yourself the outer edge of the heading indicator represents (later on that below). If you are using a BADASP this is the actual magnetic heading from the magnetometer inside that sensor platform. If you are using it with the Stratux alone, the heading is GPS-derived. When you are using it with the Stratux alone the magnetic heading will not update until you are moving and will increase in accuracy as it collects more samples. The magnetometer from the BADASP will always be the correct heading (as long as you’ve calibrated it for your plane.

The heading can be adjusted for magnetic variation in the settings dialog. The meaning of the setting is different depending on the source of the data (BADASP or Stratux). See the Settings section for more details. The difference is very important.

The airspace size is zoomable up and down by swiping up or down on the display, and the represented size is indicated in green in the bottom left corner on both portrait and landscape orientations.

The status indicators are located along the very bottom of the display with indicators for overall status (“STX”), AHRS, Traffic (“TFC”) , GPS and Sensor (“SENS”). A working Stratux should always show green almost immediately for the “STX” and “AHRS”. The “TFC” will be green if any traffic is available, even if it’s not ADS-B and will turn red if no traffic has been visible for the last 30 seconds. GPS will turn green when enough satellites have been locked that a valid GPS position can be calculated. The “SENS” indicator will turn green if you have a BADASP and it has successfully connected to the Stratux.

The landscape orientation has the same features and controls but is laid out horizontally:

Android Version: The display will auto-rotate to the orientation of the device.

Linux Version: In order to orient Stratofier in landscape mode, you need to add “orient=landscape” to the end of the “Exec” entry for the Stratofier autostart desktop entry. For details on how to do this see the Stratofier Install Page under the “Installing Stratofier” section. Also note that the Linux support has been abandoned as of January 2020. It was becoming increasingly cumbersome to maintain both and required a mess of cabling to get the HDMI to the dedicated screen. It was a neat idea but the Android solution is just better. Feel free to adapt the Android version to a dedicated screen since the source code is still easily ported. The source still supports run arguments for running on Windows or Linux for the purpose of testing without an emulator.


The menu is displayed by swiping left anywhere on the display.

Knots / MPH Depending on the airpseed display on your plane, you may want to switch this to Knots or MPH to match the speeds you’re familiar with. If you are using a BADASP the airspeed will be actual indicated airspeed. If using with the Stratux alone it will be GPS-derived. As mentioned elsewere, always use your certified avionics for critical phases of flight.

Fuel displays the fuel dialog that approximates your fuel usage and displays the approximate levels on the display on the two fuel estimator gauges on each side of the heading indicator in portrait mode or at the bottom of the attitude indicator in landscape mode. If your airplane does not use switchable tanks, turn off “Switchable Tanks” in the settings and the left tank gauge will represent both wing tanks (or your single tank in the case of say an ultralight). You only need to enter the fuel usage information for your airplane once and the app will remember them until you change it. Once you’ve filled in the specifics for your plane, you only need to update the left and right (if applicable) remaining levels before beginning your flight.

Reset Level resets the solid state gyros in the Stratux ADS-B receiver so that the current position is considered level. If you have a BADASP, it will also reset the current level position of that sensor platform as well.

Reset G resets the Stratux ADS-B receiver G sensor back to zero. The BADASP may support G-force in the future. It has the sensors but it currently doesn’t send that data to Stratofier.

Timer allows you to set a countdown utility timer in minutes and seconds, for instance as a reminder for whatever you need it for.

When the timer times out you will be presented with a popup asking Restart, Change or Done.

Shutdown will perform a system shutdown which shuts the entire system down. Note this will not remove power to the Raspberry Pi. You’ll still need to turn off power to completely shut the system down. Typically you can just power the unit off you don’t need to do a full linux shutdown.

Bug Popup

The Bug Popup is accesed by tapping the center of the heading indicator. It gets its name from earlier versions where this popup selector was only used for heading and wind bugs. It still is but also now supports the following features:

  • Overlays
  • Heading
  • Wind
  • Airports
  • Barometric Pressure (as reported by ATIS/AWOS or other)
  • Clear
  • Done
  • Overlays: Allows for turning on/off various airspace and airport overlays in the large heading indicator.
  • Heading: Adds/resets the current heading bug to the selected heading with a popup keypad.
  • Wind: Adds/resets the current wind direction bug to the selected heading with a popup keypad. Selecting the Wind bug presents two keypads. The first is for setting the wind direction, the second is the speed, which is displayed on the wind bug on the heading indicator.
  • Airports: Displays airport data for airports within a specified range.
  • Baro Press: Allows setting the barometric pressure to the BADASP sensor platform. If you don’t have a BADASP or it isn’t connected to the Stratux, it doesn’t do anything.
  • Clear: Clears both bugs from the heading indicator.
  • Done: Exits the bug popup without doing anything


Airport Type cycles through Paved, All, Grass and None which will only display airports of the selected type. This option depends on airport data having already been downloaded.

Runways turns runway extensions on for displayed airports. Runway extensions are hidden for ranges above 30 NM since the display could get overly cluttered for busy areas.

Airspaces will show available airspaces. This options also depends on airspace data having already been downloaded.

Altitudes turns on altitude indications for airspaces (displayed in gray).

Bugs & Crosswind Component

Clicking on one of the bug buttons presents a keypad for entering the desired heading. Any headings over 360 degrees are wrapped around, so a heading of 390 degrees is re-interpreted as 30 degrees. If you select the wind bug you will be asked for the wind direction followed by the wind speed which is displayed inside the bug on the outer edge of the heading indicator.

Long-pressing on the center of the heading indicator will show the angle between your set heading and the wind bugs, displaying the difference in degrees and the calculated crosswind component.

Note that the heading indicator is orange and the wind bug is cyan, with the wind speed set from the dialog displayed over the bug.

Both will rotate with the heading indicator.


This option presents a list of airports within a specified range that you can click on to show details such as elevation, runways, frequencies, etc. It’s not a replacement for a full-blown EFB it’s meant more as a quick reference.

The airport database must be downloaded in order for this option to work (see Settings below). The database is based on OpenAIP data, so it is not guaranteed to be error-free. This data is collated and made available for download from the SkyFun website within the app.

Barometric Pressure

Tapping Barometric Pressure will present a keypad where you can enter the current area barometric pressure (typically from ATIS or AWOS) which is sent to the BADASP sensor platform so it can send back accurate altitude. If you don’t have a BADASP the altitude is GPS-derived from the Stratux and this setting does nothing.


Clears the heading and wind bugs from the heading indicator, as well as any crosswind component if displayed.

GPS Details

Clicking near the bottom right where the range and magnetic deviation are displayed, will display an information page listing the current GPS satellites seen, tracked, locked, and the fix quality.

This page shows Non-ADS-B traffic that can’t be shown on the main display. This doesn’t necessarily mean that aircraft doesn’t have ADS-B out (especially in the US since it’s mandatory), it just means that no ADS-B data was detected for that transponder.

The current Stratofier version is also displayed on this page in blue. It’s a good idea to check this page after you upgrade to ensure that the version you upgraded to is what you expected.

Traffic Display

Traffic is displayed on the heading indicator in relation to you, as green dots with a directional line indicating that aircraft’s heading.

The text to the bottom right of that indicator shows the aircraft’s tail number, or ‘UNKNWN” if they aren’t broadcasting it. Below is their altitude in relation to you, rounded to hundreds (the last two zeroes chopped off). If the traffic is below you it will show a negative altitude difference and if above you will show a positive one. Note this is not their altitude it’s how many feet they are above or below you.

Aircraft (or airport vehicles) on the ground are displayed in cyan. Aircraft within 2000 feet of you vertically are displayed in yellow. Aircraft within 500 feet of you vertically are displayed in red. This color coding is used regardless how far away from you they are horizontally. Everything else is displayed in green.


The timer (shown near the bottom in the figure to the left) is set by slecting TIMER from the menu and entering minutes and seconds to count down using the standard keypad.

When the timer reaches zero, you will be presented with a small popup to choose between Reset, Change and Done.

Reset will restart the timer using the same time you entered before and start counting down again immediately.

Change will allow you to set a different countdown time in minutes and seconds.

Done exits the timer and stops showing the countdown near the bottom of the display.


Tapping help opens your device’s configured default browser to this user manual. Please note that this user manual typically lags behind the most recent updates and user interface improvements.

Stratux Off

This button shuts down the Stratux gracefully instead of just turning the power off. Personally I don’t use it but if you fear corrupting your card, you can shut down the Stratux gracefully with this button.


Switchable Tanks: Enables both fuel estimator gauges for aircraft with switchable tanks (such as a Piper Cherokee 140). This setting also affects how the fuel dialog is displayed. If switchable tanks is off, only the relevant entries are displayed there.

Magnetic Deviation: This setting has a different meaning depending on whether you are receiving valid BADASP data or not. If you are receiving valid magnetometer data from the BADASP, this offset represents a simple calibration of the magnetometer if it is slightly off. If you are using Stratux GPS-derived heading, it represents the magnetic deviation from true north for the current area. For actual BADASP magnetometer data this value should typically be less than +/- 10 degrees.

Select Countries: This allows you to select the countries for which you want data to be downloaded. Only countries with useful OpenAIP data are listed. The country selector has two tabs; airports and airspace. Selected countries are highlighted black with white text.

There are fewer useful OpenAIP databases for airspace than for airports which is why the lists aren’t identical. The United States and Canada data is very complete. I haven’t confirmed the completeness or correctness of any other countries.

Get: This button will have a green checkmark if valid data exists for the selected countries, otherwise it will have a red X icon. You need to be connected to the internet to download data. When you tap Get, it will download the selected country data from the SkyFun website. Progress is shown to the right of the Get button.

Stratux IP: This should typically be left at the default unless you are experimenting or have some special application, for instance if you have the Stratux ethernet plugged into your router.

Ownship: Enter your tail number here, or whatever is entered into your ADS-B transponder (which should almost always be your tail number). This allows Stratofier to ignore your own ADS-B data. Otherwise you will see a red airplane exactly in the center since that airplane is you.


See the BADASP page for details on the sensor platform referenced here.