Install add-on aircraft in FlightGear correctly, set the aircraft search path, fix nested folders, and troubleshoot missing or broken aircraft.
To install an add-on aircraft in FlightGear, extract the complete archive into a dedicated aircraft library, then add that library as an additional aircraft folder in the launcher. Restart the launcher and select the aircraft. If it does not appear, correct the folder depth and confirm that its directory contains a *-set.xml file.
Should I use the launcher catalogue or install the aircraft manually?
Use the launcher catalogue when the aircraft is offered there; use the manual method for a ZIP, 7z or other separately downloaded archive.
| Installation method | Choose it when | What to do |
|---|---|---|
| Launcher catalogue | The aircraft appears in FlightGear's catalogue | Use the displayed download or install control and let the launcher manage the package |
| Manual aircraft library | You have an aircraft archive or development package | Extract it, preserve its structure and add its parent folder to FlightGear's aircraft search path |
A catalogue listing does not necessarily mean the aircraft is already installed. Wait for its download to finish before trying to start a flight, and do not move or edit files in the launcher's managed package area. Our guide to using the FlightGear catalogue and organising additional aircraft explains the two sources in more detail.
Where should FlightGear add-on aircraft be installed?
Manually installed aircraft should go in a writable, permanent folder outside FlightGear's own installation and stock data directories.
A location such as Documents/FlightGear Add-ons/Aircraft is easy to back up and survives a simulator upgrade or repair. Avoid placing add-ons in FG_ROOT/Aircraft unless the package explicitly requires it: older instructions often recommend that folder, but it mixes stock and third-party files and may require administrator permission.
- Use one library if you want the simplest arrangement.
- Use several libraries to separate stable aircraft, test versions and older packages.
- Avoid cloud-only or removable locations unless every file remains available whenever FlightGear starts.
Do not overwrite stock aircraft to install a replacement or variant. A separate folder makes rollback as simple as removing one directory.
How to install a downloaded FlightGear aircraft
A manual aircraft is installed by extracting the entire package and adding the folder immediately above its individual aircraft directories to the launcher.
- Read the package instructions. Check the README for supported FlightGear releases, required base aircraft and shared folders. Confirm that the download is for FlightGear rather than another simulator.
- Create an aircraft library. Make a folder such as
FlightGear Add-ons/Aircraft. This is the parent folder that FlightGear will search. - Extract the archive completely. FlightGear cannot load an aircraft from inside a ZIP or 7z archive. Use the archive's extract function rather than opening it and copying only the visible model or texture folders.
- Locate the real aircraft directory. Open the extracted folders until you find one or more filenames ending in
-set.xml. That file identifies a selectable FlightGear aircraft or variant. - Preserve the complete package. Keep companion directories such as
Models,Nasal,SoundsandTextures. Do not change folder names or capitalisation; internal paths may depend on them. - Arrange the folder at the correct depth. Put each aircraft directory directly inside your aircraft library. If the archive contains a top-level
Aircraftfolder holding several related aircraft, add that folder as the library rather than separating files blindly. - Add the library to FlightGear. In the launcher, find the setting for add-ons, additional aircraft folders or aircraft locations; its wording varies between launcher builds. Add the parent library, not the ZIP file and normally not the individual aircraft directory.
- Restart the launcher and select the aircraft. Clear any aircraft-list search or category filter if the new entry is not immediately visible.
If the launcher is not retaining folders or basic locations are missing, first check the base FlightGear and launcher configuration.
What should the aircraft folder structure look like?
The directory containing *-set.xml should normally sit one level below the aircraft library added to FlightGear.
AircraftLibrary/AircraftName/AircraftName-set.xml
In that example, add AircraftLibrary to the launcher. A common broken arrangement looks like this:
AircraftLibrary/Downloaded Release/AircraftName/AircraftName-set.xml
The unnecessary Downloaded Release wrapper leaves the aircraft too deeply nested. Move AircraftName up one level, or add the inner folder that directly contains the aircraft directories. Collections may include several aircraft and a shared support directory, so keep those components together.
Why is the FlightGear aircraft not showing up?
An aircraft missing from the launcher is usually still compressed, nested at the wrong level or lacking a valid FlightGear definition file.
| Symptom | Likely cause | Fix |
|---|---|---|
| No new aircraft appears | The archive was opened but not extracted | Extract every file to a normal folder and restart the launcher |
| The path is accepted but finds nothing | The wrong folder level was added | Add the folder directly containing the individual aircraft directories |
*-set.xml is two or more levels down | The extractor created an extra wrapper | Remove the wrapper or select the correct inner parent folder |
| The aircraft exists but is not visible | A launcher search or category filter is active | Clear the filter and show locally installed aircraft |
| The same aircraft appears twice | Duplicate copies exist in different search paths | Keep one intended version and remove the duplicate copy or path |
| The aircraft is listed but cannot finish loading | Files, dependencies or compatible scripts are missing | Restore the full package and check its release requirements |
Restarting the launcher is worthwhile after changing a search path because some builds do not refresh the aircraft list immediately. Re-downloading will not fix a directory-level mistake.
What if there is no *-set.xml file?
A download without any *-set.xml file is usually not a complete standalone FlightGear aircraft.
It may be a livery, an update, a variant requiring a base aircraft, an incomplete archive or a package made for another simulator. A folder containing only textures is often a paint scheme; follow our instructions for putting FlightGear liveries into the required base aircraft instead.
Do not rename an unrelated XML file or create an empty -set.xml file. FlightGear aircraft definitions contain references to the model, systems and flight dynamics, so changing a filename cannot turn another package type into a working aircraft.
Why does the aircraft appear but fail to load correctly?
If FlightGear can list the aircraft but shows missing models, blank textures, script errors or dead systems, discovery worked but the package is incomplete, incompatible or missing a dependency.
- Restore omitted folders. Extract the archive again without selecting only the model or texture directory.
- Install the required base aircraft. Some downloads contain only a variant, configuration or enhancement.
- Check capitalisation. On case-sensitive file systems,
Texturesandtexturesare different paths. - Remove duplicate versions. FlightGear may be finding an older copy through another configured aircraft path.
- Check release compatibility. Aircraft written for substantially older FlightGear releases may be selectable while their cockpit scripts, instruments or systems no longer work as intended.
- Read the log or terminal output. Messages naming a missing XML, model, texture, sound or Nasal script often identify the exact file or dependency at fault.
A missing interactive cockpit is not always an installation fault; some aircraft provide only a limited cockpit or external model. Check the package description before treating an absent feature as corruption. Our recommendations for finding compatible, properly packaged FlightGear aircraft also cover the checks to make before installing an older add-on.
Why is the aircraft greyed out in the launcher?
A greyed-out aircraft usually represents an uninstalled catalogue package, an unfinished download or a variant whose required base package is unavailable.
Check the status text shown beside the entry and allow any managed installation to complete. If the aircraft is selectable but the start control remains disabled, choose a valid aircraft and departure location and resolve any installation error reported by the launcher. Copying the same files into FlightGear's stock directory will not repair an invalid definition or missing dependency.
How do I update or remove a FlightGear aircraft?
Update a manual aircraft by replacing its complete directory, and remove it by deleting that directory while FlightGear is closed.
Do not merge a new release over an old one unless its documentation specifically instructs you to do so. Merging can leave obsolete scripts and models behind, producing faults that are difficult to distinguish from version incompatibility. Back up any user-added liveries first, then rename or remove the old folder and extract the replacement cleanly.
When uninstalling, leave the parent search path configured if it still contains other aircraft. Do not delete a shared support directory until you have confirmed that no remaining aircraft package uses it.