Frequently asked questions

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Thank you for your interest in FlightGear! This FAQ lists some of the most commonly asked questions. Please create a topic at our forum if you cannot find the answer on your problem(s).


Where can I get FlightGear?

The official download page is Precompiled binaries are available for Windows, and most Linux users will find that most distributions have a packaged version of FlightGear (the package name could be fgfs or flightgear.

How do I install FlightGear on Linux?

Many distributions include FlightGear in their repositories. If you can't find a packaged version for you, consider downloading and compiling from sources.

Where can I find the latest development source code?

The latest development code is available for everyone through our Git repository.

Where do I get the scenery? What is available?

While the base package only comes with scenery for the San Francisco Bay area, you can currently fly just about anywhere in the world. Currently Terrasync is the best option: it downloads the latest scenery while flying. See its page for usage information.

However the latest scenery could be too demanding if you have a low end computer or not much RAM, so consider instead to manually install the old scenery from the "graphical interface" available at the scenery download page.

Where can I get different 3D models for my plane?

Official FlightGear aircraft can be found at Download central. Other aircraft in development can be found on Git, and some other aircraft can be found on 3rd party FlightGear hangars.

Why are the aircraft at out of date?

The official aircraft downloads are only updated at the time of a new release of FlightGear. This is done because aircraft that are currently in development are usually developed on development/unreleased versions of FlightGear. Those development versions have lots of features that are not supported by the (older) stable release. Would we update the aircraft downloads more often, most aircraft wouldn't work on the stable release of FlightGear.

How current is the data in FlightGear compared to the real world?

We use the same navaid and airport dataset that X-Plane uses. The current dataset can be found in the $FG ROOT/Navaids/ and $FG ROOT/Airports/ directories. The maintainer can be found at X-Plane Airport & Navigation Data.

Why don't you charge money for this?

FlightGear can be downloaded for free from many locations including the FlightGear website, but can also be bought on a CD. Although we offer that service (see the website), we encourage other groups to redistribute it for their users, especially within an operating system distribution which makes installation even faster and easier for new users.

Occasionally you may see FlightGear for sale on auction sites or commercial websites under some other name. This can be done quite legitimately as long as the terms of the license are upheld and might be worth the cost if some value-added features such as additional scenery, aircraft or after-sale support are included. Unfortunately, most cases seen to date appear to be just someone trying to make money selling something that is free and providing no real added value.

How can I get started with FlightGear?

The latest release of FlightGear and its aircrafts can be downloaded at the download central. Be aware of hardware requirements! Also, check out New to FlightGear.


How do I compile FlightGear from source?

See Building FlightGear. There are explanations to compile in Windows, Linux and even scripts to automatically download and compile the whole thing.

Why won't FlightGear compile?

Well, that depends. First make sure you are using the appropriate versions of FlightGear, SimGear, plib, zlib. If any of the packages are out of sync with the others, compilation may fail. See also Building FlightGear

The FlightGear Downloads page should tell you what versions you need if you are trying to compile the latest stable release. If you are using a development snapshot, make sure all three packages are up-to-date.

Also ensure that you have some implementation of OpenGL with glut support with the appropriate header files. Linux users with nVidia cards should make sure you have the latest drivers from nVidia. Other Linux users make sure you have Mesa3D ( and your X server installed correctly.

If your problems persist, ask in the FlightGear Forums, on the IRC or subscribe to our FlightGear-Users mailing list and let us know what problem you're having.

What is SimGear, and why do I need it?

SimGear is a library of supporting code. SimGear is only needed if you plan on compiling FlightGear — it is not needed to run precompiled binaries. For more information see Note: When compiling FlightGear it is very important to have the matching version of SimGear.

Configuring and running

How do I start FlightGear?

The easiest way is using FlightGear Launch Control. Otherwise, you can run it from the command line, with the proper options.

How do I install new scenery?

If you really don't want to/can't use Terrasync, the scenery archive files (ie. w100n30.tar.gz) should be decompressed into the Scenery/Terrain directory in your $FG_ROOT. More at Howto: Install scenery.

How do I setup my joystick(s)?

FlightGear supports wonderfully many joysticks/yokes out of the box. However if you're having problems see Input device.

What is fgfsrc? What format should my personal .fgfsrc file be in?

.fgfsrc is a file that can contain a list of Command line options with one option per line. The file is not an XML file. Note that also Windows installations have this file.


Why won't my engine(s) start?

Aircraft vary in their starting procedure. Some may have an auto-start sequence menu entry or instructions in the aircraft help menu (Press "?") and/or at the aircraft's wiki. Please consider reading the FlightGear Manual: this is a flight simulator, not a flight simulation game!

Starting engine in single-engine aircraft

In general to start the engine on a piston-engine type aircraft, you need:

  1. Fuel - You can run out of fuel, of course, but for certain aircraft, FlightGear may load it with no fuel, making it impossible to start the engines. Check this in the menu Equipment > Fuel and Payload.
  2. Correct mixture (generally "rich", ie red knob all the way in)
  3. Magnetos on (R, L, or both--generally select "both")
  4. Throttle (some engines start better with a little gas)
  5. Hold starter for sufficient time.

You may be able to do all these functions with the standard 2-D panel or your aircraft's built-in panel. However using the standard key bindings is more reliable:

  1. Press/hold "m" to set mixture to rich (m=rich, M=lean--if you are at a very high elevation you may need to set it somewhere besides full rich)
  2. Press "}}}" (three times) to set magneto to R, L, and finally "Both".
  3. Open throttle a little.
  4. Press "s" to run the starter. For some aircraft you may have to hold "s" as long as 10 seconds before the engine starts.

These instructions may not work for jet aircraft, helicopters, or other types of aircraft with complex start procedures. Check the instructions in the aircraft help menu (Press "?") and/or at the aircraft's wiki.

In general to start the engine on a jet engine type aircraft, you need to:

  1. Set cutoff ON
  2. Engage the starter
  3. Once the engines spools up to approximately 5% N1, set cutoff OFF
  4. Disengage the starter once the engine has reached operational speed

Starting engine in multi-engine aircraft

Starting all engines in a multi-engine aircraft is similar to the single engine--except you must follow the same start sequence for each and every engine. Flightgear provides a convenient way to do this for all engines at once.

Note that the default 2-D panel is connected to only one engine. So if you try to start the engines using the 2-D panel controls you will most likely start only one engine.

Instead, use the keyboard to start all engines at once:

  1. Press "~" (select all engines)
  2. Press/hold "m" to set mixture to rich (m=rich, M=lean--if you are at a very high elevation you may need to set the mixture somewhere besides full rich)
  3. Press "}}}" (three times) to set magnetos to R, L, and finally "Both".
  4. Open throttle a little (it now controls all engines).
  5. Press "s" to run the starter (it now runs the starter on all engines). For some aircraft you may have to hold "s" as long as 10 seconds before the engine starts.
  6. Rev the engines a little with your throttle and check your tachometers and/or visually to be sure all engines are running.

If the engines won't start, make sure you have fuel. Some aircraft have switches to control which fuel tanks feed which engines, so check these. Make sure each engine you want to start is connected to a tank that has fuel. Check fuel tanks in the menu Equipment > Fuel and Payload.

These instructions may not work for jet aircraft, helicopters, or other types of aircraft with complex start procedures. Check the instructions in the aircraft help menu (Press "?") and/or at the aircraft's wiki.

Where is the moving map?

In game, you can go into the menu "Equipment > Map", but there won't be any aeronautical chart. A popular moving map display is available under a separate project called Atlas. Also, MPmap is an online map for multiplayer.

If you like an alternative to Atlas with updated graphics and mapping provided by the OpenStreetMap project, then check out Flightgear Mapping fgmapping or JMapView.

Where can I learn about instrument flying and navigation?

There is a nice article at Understanding Navigation, and a lot is very well explained into the FlightGear Manual. Other resources are:

What is the difference between Aileron and Rudder?

There is a bit of info on aileron vs. rudder in the very same book...

Is there support for multi-player flying?

Yes, sure we have it! See Howto: Multiplayer. Both the Windows and *nix versions of FlightGear are capable of multi-player flying on FlightGear servers. Also voice communication is supported, with FGCom.

A map showing players aircraft online in real time is available as MPmap.

Where are the best places to fly in FlightGear?

FlightGear scenery covers the whole world, but thanks to the FlightGear user community, certain airports and areas are more detailed than others. As a general idea:

  • There are a lot of high-quality scenery models around Paris, France.
  • EHAM Amsterdam Schiphol, EGKK London Gatwick and LFPG Paris Charles de Gaulle are some of the highest quality airports.
  • LOWI Innsbruck is both developed in scenery and airport.
  • TNCM St. Maarten is a popular destination, and the surrounding islands (Anguilla, St. Eustatius, Saba, St. Barthélemy, St. Kitts, and Nevis) are all well-modeled.

Furthermore, see Suggested Flights, Suggested Airports and Suggested custom scenery.

Where can I find airport info and aeronautical charts online?

See Getting aeronautical charts.

Is there support for any military scenarios like dog fighting or bomb dropping?

Yes. Check out the Bombable add on and Bombable's forum thread. There are also third-party bombing scenarios for the A-10 and other aircraft with armament, like the North American OV-10A Bronco, General Dynamics F-16 and F-117 Nighthawk.

Flying issues

Why are my controls returning to a particular position?

There are several possibilities that can lead to this:

  • If your aircraft's autopilot is enabled, it will take over (some of) your controls. Switch the autopilot off to regain control.
  • Some laptops have an onboard gravity sensor, that might be detected by FlightGear as a joystick. You can set FlightGear to ignore this fake-joystick:
    1. Get your accelerometer's name via the in-sim Help > Joystick Information dialog.
    2. Add this name to your $FG_ROOT/Input/Joysticks/Accelerometers/accelerometers.xml file, enclosed by <name> and </name> tags..
    3. Report your device name to #flightgear at, so it can be included in the "official" accelerometer.xml file.

Why does my cockpit disappear when looking around?

Probably you're using a 2D-panel version of an aircraft. Be sure to pick the one with a 3D cockpit. Most of the aircraft now have it!

There are lots of other aircraft flying around

Flightgear has a so-called AI-traffic system. This system generates other, computer-controlled aircraft based on real flight plans to make the FlightGear world look more alive. To disable it, uncheck the proper option in FGrun.

If on the contrary you can't see any aircraft other than yours, consider contributing to add traffic to your favourite place!

I can't make this plane fly straight, it keeps turning left!

Yes, FlightGear is a real flight simulator and simulates that too. Exactly, that's how real propeller aircraft behave. See Understanding Propeller Torque and P-Factor.


For anyone who's willing to contribute, we have dedicated to you the Developer portal and a Volunteer page that explains all the nice things you can do.

What language is FlightGear written in?

Mostly C++ with some supporting C code that's primarily contained within SimGear. See the code analyses at Ohloh for more details on the used languages:

As you seem to be interested in core development, you should really check out Howto:Start core development.

How do I design a flight dynamics model for a new aircraft?

FlightGear supports various flight dynamics models (FDMs), but just two of them are commonly used:

  • JSBSim: see
  • YASim: if you want a simpler FDM to work with, try your hand at YASim. For a guide on creating YASim aircraft, look in the FlightGear base package for $FG_ROOT/Docs/README.yasim.

See the Aircraft development portal.

How do I place objects, like buildings, into FlightGear?

The most up to date solution is using the UFO. See Howto:Place 3D objects with the UFO. The UFO will give you the interface to choose one of the available objects and place it to some grade of precision into FG world, and then export that data to be uploaded to the official scenery, or for personal use. For more, see the Scenery development portal.

Where can I learn 3D programming and how do I get involved?

If you'd like to create a 3D cockpit for FlightGear, or to create buildings, external aircraft models, etc., your help is desperately needed. Try to go easy on the triangles, so that your work will be enjoyed by as many people as possible. The most commonly used tools here are Blender, AC3D, Gimp.

If, on the other hand, you really want to get your hands dirty with C++ coding, you'll have to buy a good OpenGL book eventually. However, FlightGear uses OSG, a high performance 3D graphics toolkit. To get started with 3D C++ coding, you can take a look at the OSG documentation and learn only as much OpenGL as you need, when you need it.

How do I add an airport?

This process includes creating the airport layout in WorldEditor, testing it (you might want to generate part of the scenery, but this is not mandatory) and then, if your data sources are GPL compatible, send it to Robin for inclusion in the shared airport database. The airport will be available in the next full rebuild of the scenery, unless you want to generate your own scenery. More at Howto:Make an airport.

Can I generate my own scenery?

Yes, though it can be a difficult task. FlightGear's scenery generation is handled by a sister project, TerraGear. The good news, though, is that once you have set everything up it's quite easy (although might be time consuming), and above all that you can easily share it.


X doesn't work / is broken / is wrong / won't run

FlightGear is a very complex program. If you need help in general usage of the game you'll find it at the User portal and at the our forum.

If your problem is instead software crashes, you're getting errors, etc..., please consider the following:

Some of the most common issues are however listed below. If you can't solve the problem on your own and need the help of someone, please remember that we're all here for fun, developers included, and that any help is an act of generosity. So try to be nice, even if the problem is frustrating you.

Unable to execute file: bin/Win32/fgrun.exe during installation

This article or section contains out-of-date information

Please help improve this article by updating it. There may be additional information on the talk page.

Your system is missing the MSVC runtime libraries required by FlightGear. Download and install the following vcredist_x86.exe:

What happened to the panel, keyboard, etc?

The problem is almost certainly that your base package is out of sync with FlightGear. Many configurable parts of FlightGear are defined in XML files contained in the base package.

Why is FlightGear so slow?

If it seems just slow, see if you can fiddle with graphics settings here: Howto: Improve Framerates.

If things are pathologically slow (i.e. ~1 frame per second), maybe 3D hardware acceleration is not activated. Make sure you have OpenGL libraries installed and configured properly and make sure you have the latest drivers for your video card. Also, be ready because some cards are not well supported.

How do I see the Frame Rate?

On the in-sim menu select View > Display Options, then check the box that says "Show frame rate".

Stuck upside down after "crash"?

In his infinite wisdom the FlightGear Grand Master decided that planes were too valuable to allow them to be destroyed by novice pilots who seemed to crash a lot. The fact that nobody has bothered to model crashes may have something to do with it too. :-)

The result of this as you have noticed is that with a little practice an ingenuity you can trim the ship to fly inverted along the ground. The quick answer is to reset the sim, via the File > Reset menu. This will place your aircraft back at its starting location.

For the stubborn people out there: The trick to learn is to roll back to normal (non inverted) do this by nursing the elevator to get to about 500 feet or so and use the ailerons to snap roll 180*. This is all good avionics except for the plane not destroying itself. Remember the controls work in reverse when you are inverted and keep that airspeed up!!!

Why won't the latest versions of some aircraft work in my (older) version of FlightGear?

Often new aircraft development keeps pace with the latest FlightGear code development. New or newly modified aircraft may rely on files (such as new instrument files) or features, only available with newer versions of FlightGear. If you are stuck with an older version of FlightGear, you can try downloading an earlier version of the aircraft at one of the archives:


Where can I get the latest version of this FAQ?

Who do I contact if I have comments about this FAQ?

Add your comment to this FAQ's discussion page.

How old is this document?

Check its history.

What other important documentation should I read?